Tag Archives: electricity

Air conditioner use under climate change will overload the USA’s electric grids

The United States could run its electric grid into the ground using air conditioners if climate change continues at its current pace — and there’s no indication that it’s going to stop.

A study of household-level electricity demand from the American Geophysical Union warns that an increase in the use of air conditioners (AC) in the USA is likely to cause massive issues in the future. This increase in use will be driven by climate change. Higher peak temperatures in the summer and longer, more frequent heat waves will increase usage enough to overwhelm national electricity grids as they are now.

Unless the grids are modernized to become more effective or receive increased capacity, the USA stands to expect rolling blackouts.

Chilling prospects

“We tried to isolate just the impact of climate change,” said Renee Obringer, an environmental engineer at Penn State University and lead author of the new study. “If nothing changes, if we, as a society, refuse to adapt, if we don’t match the efficiency demands, what would that mean?”

The researchers projected how summertime energy usage will evolve in the future, under two scenarios: these assume global temperatures rise 1.5 degrees Celsius (2.7 degrees Fahrenheit), or 2.0 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels. Based on these temperatures, they estimate that electricity demand in the USA would increase by 8% and 13% overall, respectively.

Based on our current emissions, we’re well on the way to exceed the 1.5 degrees Celsius warming scenario by the early 2030s, according to The Intergovernmental Panel on Climate Change (IPCC) 2021 report. In fact, without significant effort, we’ll likely exceed the 2.0-degree Celsius threshold, as well, by the end of the century.

This study is the first to analyze the impact of higher temperatures on electricity demand and peak load for specific cities or states. It is also the first to project residential air conditioning demand at a wide scale. Environmental data used in the projections included air temperature and heat, humidity and discomfort indices, alongside air conditioning use figures, collected by the U.S. Energy Information Administration (EIA) in 2005-2019 from statistically representative households across the contiguous United States.

That being said, the findings are not perfect; the study only took into account the influence of climate on air conditioning use. Additional factors such as population increases, changes in income, consumer behavior, or other factors that can affect air conditioning demand, were not taken into account.

It is possible, says the team, for technological improvements (such as better insulation or improved AC efficiency) to come along and make it possible to cover the increased demand for AC without extra energy drain. The team calculated that an increase in efficiency of 1% and 8% would be required for this. This figure varies with existing state standards and how much demand is expected to increase there; Arkansas, Louisiana, and Oklahoma would need the most increases.

Heat waves will pose an especially difficult time for our grids, and also present the highest risk of death for the public. Worse still, energy generation tends to fall below its peak during heat waves, further compounding the problem. In this scenario, it’s very likely that energy utility companies will be forced to stage rolling blackouts to avoid grid failure during heat waves.

The south and southwest regions of the country will see the greatest increases in energy demand. For the state of Arizona, for example, if all households increase AC use by 6% — which the team estimates will be needed to offset 1.5 degrees of extra warming — the whole state will see an increased monthly demand of 54.5 million kilowatt-hours.

The new study predicted the largest increases in kilowatt-hours of electricity demand in the already hot south and southwest. Under the 2.0-degree Celsius scenario, some cities in the area, such as Indiana and Ohio, could see triple their current energy demand over the summer months.

The paper “Implications of Increasing Household Air Conditioning Use Across the United States Under a Warming Climate” has been published in the journal Earth’s Future.

What was electricity up to before we discovered it?

Electricity — you couldn’t read ZME Science without it. Would life really be worth living like that? Probably not.

Image via Pixabay.

Luckily, we do have electricity running merrily through our cities and homes, our cars, our planes. We’ve had it for over two centuries now, thanks to the combined efforts of many brilliant minds. But like anything else discovered and not invented, electricity was already a thing in nature before people noticed and learned how to harness it.

Which raises a question — what are some examples of natural electricity?

Ancient currents

Humanity’s earliest knowledge of electricity undoubtedly came from lightning bolts. They represent huge discharges of electrical current, and they’re extremely visible, so we can say for sure that people have been aware of them ever since we first became aware of anything. For all its showiness, lightning was just too powerful and unpredictable for early humans to analyze and understand. They could see that a bolt of lightning would start fires (a theory goes that that’s how humans first learned to use fire), but any direct experiencing of its properties was likely to result in death — which tends to stifle scientific progress.

But there is another, more survivable source of natural electric current: animals. Fish, mostly. Electric eels, electric rays, and electric catfish have been known since antiquity, likely earlier. However, our first evidence of this comes from Antiquity.

Texts from ancient Egypt dating to around 5000 years ago showed that the electrical properties of some fish were already known at the time. They considered the electric catfish to be the protector of all other fish, calling it the “Thunderer of the Nile“. It’s particularly interesting to me to see that they did understand there was an association between thunder and electricity (or maybe it’s just a fluke of translation). Ancient Greek, Roman, and Arabic documents also make note of such fish.

Image credits Keli Black.

Pliny the Elder wrote in Naturalis Historia about the numbing effects of shocks from electric catfish and electric rays, and that they could travel along conductive substances. Since people could feel the effect of these shocks but didn’t understand them, they had a lot of theories about what they were and what they could do. Touching electric fish was sometimes recommended against painful ailments (perhaps due to the numbness they caused) such as gout.

It’s possible that Pliny also had access to ancient Greek texts that discussed electrical animals. But they also studied the nature of static electricity — although it’s unlikely they understood that the two were related — which they believed was a form of magnetism. Some substances would need to be rubbed to become magnetic, they argued, while others (such as magnetite) were naturally magnetic. It does seem a bit of a stretch, looking back, since their theories were based on charging bits of amber by rubbing them, which would then attract light items such as feathers or strands of hair. But magnets don’t attract these same items, so it would be exceedingly easy to prove that it wasn’t the same phenomenon.

Still, there is evidence that at least some ancient peoples had a better grasp of electricity, how to generate it, and some of its uses. The Parthian Battery or Baghdad Battery is eerily reminiscent in structure to (you won’t believe this) a battery. It was made up of a clay pot, with copper and iron rods placed inside. It could have been used for electroplating, which involves using electrical current to plate an item with an atomic-thin layer of another metal (such as gold). That being said, it could also have been a fancy scroll holder, we just don’t know.

These are the historical accounts we have of electrical phenomena. Curiosity would drive people to them and towards their understanding, eventually culminating in the discovery of electricity.

Still, these are just the ones our ancestors could perceive. There are several other sources of naturally-occurring electricity, and some of them can get quite spicy.

Ball Lightning

Ball lightning sounds like a Dungeons and Dragons spell, but it’s a real thing. NASA even knows how to make some.

Reports of such lightning balls are patchy, but some of these reports are centuries old. We don’t really know what causes it, why, or how, but we know it exists. The best way to describe it is as spheres of plasma or lightning of various sizes and of much longer duration than a lightning bolt, up to minutes in some cases. Such spheres float or zip around, witness accounts vary, but they seem to be particularly associated with thunderstorms and other instances of electrical discharges.

Ball lightning seems to be capable of taking on a wide range of colors and sizes, but it tends to be comparable in brightness to a lamplight. Witnesses report being able to perceive it in daylight, and that its brightness stays more or less constant throughout its duration. It’s possible that ancient peoples saw these balls of lightning as well, and that they laid the foundation for stories of whisps, ghosts, or other shiny beings.

Contact with it is probably not advisable, which is a good rule of thumb for any kind of lightning, really, although we don’t really know its effects on contact.

Volcanic Lightning

Mount RinjaniIndonesia, 1994. Cool. Image via Wikimedia.

With a name fit for a heavy metal band, volcanic lightning forms during volcanic eruptions. Friction between particles of ash in the hectic moments of an eruption generates powerful electrostatic charges in a process similar to that in a stormcloud. Eventually, all that energy has to go somewhere, so it discharges in the form of lightning.

We actually have very reliable evidence that ancient peoples knew of volcanic lightning. Pliny the Younger, the nephew of Pliny the Elder, describes the eruption of Mount Vesuvius in 79 AD as being “at intervals obscured by the transient blaze of lightning”.

Aurora Borealis

The northern lights are the product of interactions between the Earth’s magnetic field and charged particles incoming in solar wind. In essence, these particles carry an electric charge which causes them to be repulsed by the magnetic field.

So technically, they form an electrical current. The light and colors are given off by gas particles in the atmosphere becoming ionized (energized) by this current. The color given off is a product of the frequency these particles vibrate on. In the higher layers of the atmosphere, emissions tend to be low-frequency shades of red. These turn more towards green and blue at lower altitudes and ultraviolet at the lowest altitudes.

You might be surprised, however, to find out that the northern lights also make a sound: a hiss-like, cracking sound.

Galvanic corrosion

Batteries turn chemical energy stored in metal bars into an electrical current. That process is known as galvanic or bimetallic corrosion.

Corrosion at the meeting points of mild steel and stainless steel. Image via Wikimedia.

Galvanic corrosion involves the breakdown of a metal with lower electric potential (the ‘less noble’ one) when it is in contact with a metal that has high potential (‘more noble’) through an electrolyte solution. The greater the difference between these potentials, the more power is produced. The flow of ions tapers off as the anode corrodes, which is why batteries slowly stop producing power. However, corrosion at the cathode is inhibited, with incoming ions depositing on its surface.

The earliest official record of this process comes from the 17th century, when the British Admiralty had to remove the lead plates used as sheathing on its ships to prevent iron elements from corroding. Later on, they tried installing copper plates instead (metal was used to coat the wooden bodies of ships to protect them against algae, parasites, and pests). They too had to be removed, as they were eating through the iron rivets used to fasten them to the hull.

Water, especially saltwater, is a very good electrolyte. In essence, tiny batteries formed at the contact between the plates and iron parts or rivets. This process is pretty much unavoidable wherever two metals come into contact and there’s humidity in the air. Modern equipment and infrastructure such as bridges sometimes use a sacrificial anode designed to be corroded and protect other metals, acting as a lightning rod for corrosion.

Another way to do it is to insulate these metals properly. The admiralty found that some of the iron rivets were in perfect condition. The copper plates, they discovered, were delivered to the shipyards in a waxy paper wrapping. Workers wouldn’t always bother to remove this before bolting the plates, and sometimes it caught on the rivet. This would insulate it from the copper, preventing oxidation.

In stars and planets

The Sun, being a huge fusion reactor, generates impressive magnetic and electric fields. One manifestation of an electrical current on its surface is the sunspot.

Our Earth’s upper surface is brimming with massive, low-intensity, and low-frequency telluric currents. They’re primarily generated by changes in the planet’s outer magnetic layer, which in turn is primarily influenced by the sun. Therefore, these currents tend to have a day-night variation and they’re relatively changeable. They also pass through oceans.

In animals

You quite literally could not read ZME Science without electricity. Not even printed out. Our brains need it to function.

Whenever one of your neurons wants to say something to its mates, or send an instruction to your pinky, it has to generate an electric charge to do it. Computers, or Morse code, work using a very similar principle: 1 or 0, signal or no signal, current or no current. These can be compounded to form coherent messages.

Instead of sending them down a wire or processor, our brains do it with ions, charged particles, which bounce on nerve bundles to their destinations. The data our senses perceive is coded into electrical signals and sent to the brain, where it is processed using electrical signals. Any needed response is transmitted back using electricity.

The electromagnetic force is one of the four fundamental forces of the universe. They’re like its constitution, and all the other natural laws follow from their interactions. Electricity is one side of this force, the other being magnetism. We tend to think of them as things that you only find in a wall socket or in a lab, but they’re directly involved in everything.

But what fascinates me most is the thought that what I consider to be myself, my mind and memories and personalities, are shaped through electricity in a way. Hopefully, those fundamental laws won’t get overturned anytime soon, because I have a lot of data that I did not back up.

University of Utah mechanical engineering associate professor Mathieu Francoeur. Credit: Dan Hixson/University of Utah College of Engineering.

New nanodevice converts wasted heat into more battery life

A mechanical engineer at the University of Utah has found a ‘loophole’ around a physical principle that allows a device to convert wasted heat into electricity. The nanotechnology harvests heat from an object by placing two surfaces until they’re almost contacting one another. In the future, this setup might not only be able to cool down mobile devices like laptops and smartphones but it may also be able to channel their heat into more battery life.

University of Utah mechanical engineering associate professor Mathieu Francoeur. Credit: Dan Hixson/University of Utah College of Engineering.

University of Utah mechanical engineering associate professor Mathieu Francoeur. Credit: Dan Hixson/University of Utah College of Engineering.

The device in question, called a “Near-Field Radiative Heat Transfer Device”, was elaborated by Mathieu Francoeur, a mechanical engineering associate professor at the University of Utah. In order to harvest heat, this device blows past the so-called blackbody limit.

A black body is an object that absorbs all the electromagnetic radiation (i.e. light) that strikes it. However, in order to stay in thermal equilibrium, the black body must also emit radiation at the same rate as it absorbs it. For this reason, a black body also radiates well — it’s why stoves must be black.

The theoretical blackbody limit tells us the maximum amount of heat that can be emitted from an object. However, this ceiling is known to be no limit at all when the spacing between objects is small enough.

Francoeur and colleagues devised a 5mm-by-5mm chip, which is no bigger than an eraser head, made of two silicon wafers spaced by a nanoscopic gap only 100 nanometers thick — that’s one thousandth the thickness of a human hair.

“Nobody can emit more radiation than the blackbody limit,” he said. “But when we go to the nanoscale, you can.”

The chip was placed in a vacuum. The researchers then heated one side of the chip and cooled the other side separated by a tiny gap, creating a heat flux that can be converted into electricity. Generating electricity in this manner is not novel, but where the new study shines is in its demonstration of fitting two silicon surfaces close enough to achieve this effect without them touching each other. The closer the two surfaces are to one another, the more electricity can be generated.

About two-thirds of the energy consumed in the U.S. each year is lost as heat. Francoeur envisions a version of his chip in the future which cools down laptops and smartphones and channels extra electricity to the battery. He estimates that battery life could potentially be improved by 50% using this technology. For instance, a laptop with a six-hour charge could last nine hours. The blackbody chip could also be used to up the efficiency of solar panels or in automobiles to convert heat from the engines to power the electrical systems.

“You put the heat back into the system as electricity,” he said. “Right now, we’re just dumping it into the atmosphere. It’s heating up your room, for example, and then you use your AC to cool your room, which wastes more energy.”

The findings were published in the journal Nature Nanotechnology.

Bitcoin to consume 0.5% of the world’s electricity — as much as Ireland

Everyone’s favorite cryptocurrency is turning out to be a massive energy sink. According to a new study, in 2018, Bitcoin will soon account for 0.5% of the planet’s electricity — more than the consumption of many sizeable countries.

Cryptocurrency promised to revolutionize how we pay and receive money, and while they haven’t really done that, they did make a few people very rich. Aside from that, the social promises made by cryptocurrencies have yet to be fulfilled, and we’re starting to see some of the downsides of cryptocurrencies — in this case, energy consumption.

Most of the Bitcoin-related energy is consumed in the “mining” process. Mining is essentially a record-keeping service done through the use of computer processing power. Miners keep the blockchain consistent, complete, and unalterable by repeatedly grouping newly broadcast transactions into a block, which consumes a massive amount of energy (the blockchain itself is a list of records linked and secured using cryptography).

The problem is that you can’t really have Bitcoin without immense computation, and this level of computation will always require vast amounts of energy. Miners are incentivized to use more and more processing power and even those who don’t get anything expend electricity.

If Bitcoin miners were a country, they’d rank somewhere between the 60th and 70th for consumed electricity — that’s more than half the countries in the world.

In a Commentary appearing on May 16 in the journal Joule, financial economist and blockchain specialist Alex de Vries analyzes this energy consumption using a new methodology.

“The electricity that is expended in the process of mining Bitcoin has become a topic of heavy debate over the past few years. It is a process that makes Bitcoin extremely energy-hungry by design, as the currency requires a huge amount of hash calculations for its ultimate goal of processing financial transactions without intermediaries(peer-to-peer). The primary fuel for each of these calculations is electricity.”

His estimate put the minimum current usage of the Bitcoin network at 2.55 gigawatts annually, though the real figure is likely much higher. That’s about as much as Ireland, and two times more than countries like Paraguay and Lithuania. A single transaction uses as much electricity as an average household in the developed world uses in a month, and to make matters even worse — things are only going to get worse as Bitcoin-related energy consumption increases.

“To me, half a percent is already quite shocking. It’s an extreme difference compared to the regular financial system, and this increasing electricity demand is definitely not going to help us reach our climate goals,” he says. If the price of Bitcoin continues to increase the way some experts have predicted, de Vries believes the network could someday consume 5% of the world’s electricity. “That would be quite bad.”

This raises two important questions. First, is Bitcoin really adding any value to society? Sure, you can speculate around it, maybe make some money, maybe lose some money. But at the end of the day, for mankind, is Bitcoin really adding anything of value — especially considering how you spend electricity (and therefore money) to generate it? Secondly, there are important externalities associated with Bitcoin. It’s not just the money, but also the emissions generated in the electricity-producing process — who will account for that? Some states are already taking the first steps towards Bitcoin regulation, and that’s really important, not just for what’s happening now, but for what will undoubtedly happen in the future.

“But you need to base your policy on something. And I think that my method is important in that regard, because it’s very forward-looking. It’s focused not on the now, but on where we’re headed. And I think that’s something you really need to know if you’re going to draft policy about it,” he says.

Mining Bitcoins gets harder and harder, so at one point, the cost of electricity will outweigh the Bitcoin revenue. But we’re still a long way from reaching that equilibrium, and it doesn’t make much sense to wait for that to happen — after all, a new currency could come up and take Bitcoin’s place, and then we’re back to square one. As de Vries concludes:

“For now, however, Bitcoin has a big problem, and it is growing fast.”

Journal Reference: Joule, de Vries: “Bitcoin’s Growing Energy Problem” http://www.cell.com/joule/fulltext/S2542-4351(18)30177-6

Why does electricity hum — and why is it a B flat in the US, and a G in Europe?

The electricity hum (also called the “mains hum”) emerges because electricity runs on alternating current (AC), which transposes voltage in the pattern of a sine wave. In the US, the frequency of this current is 60 Hz, which creates a tone almost exactly halfway between A♯ and B. In Europe, it’s 50 Hz tone, which is closer to a G. If that doesn’t mean much, let’s look at it in a bit more detail.

Alternative current

There are two types of current: direct and alternative. Direct current (DC) is a unidirectional flow of electric charge; think of current flowing from a battery, that’s DC. Alternating current, on the other hand, is less intuitive. As the name implies it, it alternates — it periodically reverses direction. Alternating current is how electric power is delivered to businesses and residences, where its voltage can be increased or decreased with a transformer.

As a result, while the voltage of direct current is a straight line, the voltage of alternating current is a wave, most commonly as a sine wave, as can be seen below.

Alternating current (green curve). The horizontal axis measures time; the vertical, current or voltage. Typically, it oscillates tens of times a second. Image via Wikipedia.

Our modern society is pretty much built on alternating current. All the devices in our day to day life need current, and that almost ubiquitously comes as alternating current. But as James Clerk Maxwell showed in the 19th century, electrical current and magnetism go hand in hand. Sometimes, stray magnetic fields cause the enclose and accessories to vibrate, generating an electric hum. Secondary sources are magnetostriction and corona discharge around high voltage power lines.

The “hum” intensity is a function of the applied voltage, which brings us to the next point.

Current and sound

In music, a note is governed by its pitch, which is based on the frequency of the sound. The higher the frequency, the higher the pitch. Generally speaking, a scale starts with A, which is 440 Hz. If you go an octave below, you’d get another A at 220 Hz. The next (lower) A is at 110 Hz, then at 55 Hz, and so on. Since the electrical hum depends on the frequency of the current, so the sound will pretty much have the same frequency as the current. In the US, the current frequency is 60 Hz tone. The 60 Hz tone is almost exactly halfway between A♯ (58.24 Hz) and B (61.68 Hz). However, the 60 Hz frequency is pretty much only used in the Americas (mostly), Saudi Arabia, South Korea, the Philippines and about half of Japan. The rest of the world uses 50 Hz current frequency, which means that the note resulting from the electrical hum is closer to a G (a bit sharp).

Hums can also appear at the frequency harmonics, though with a much lower intensity. So in the case of a 60Hz current, you could have some humming at 120 Hz, 240 Hz, and so on, up until very high frequencies. There’s an entire spectrum of electrical hum. In terms of sound, that means you not only output the original note, between A♯ and B, but also the same note one octave higher, and another one, and so on.

The spectrum of an example of mains hum at 60 Hz.

Getting rid of and using electrical hum

Generally speaking, the hum is an annoyance, especially in musical instruments that involve electricity. At a venue, this electrical hum is often picked up via a ground loop. In order to fix this, stage equipment often has a “ground lift” switch which breaks the loop. An alternative way to fix this is the audio humbucker. Electric guitars especially (and sometimes microphones) use one or several humbuckers, which are basically two coils instead of one. The two coils are arranged in opposed polarity so that the AC hum is cancelled, while still producing the intended signal for the sound.

However, electrical hum can sometimes be important — especially in forensic analysis. Forensics use a technique called Electrical Network Frequency which allows them to validate audio recordings. They compare how the frequency changes in the background mains hum to a pre-existing database. Basically, they use the mains hum signal as a digital watermark which can identify when the recording was created and help detect any edits in the recording. In the German federal state of Bavaria for instance, this technique has been used by authorities since 2010.

Congrats Germany! Credit: Pixabay.

Germany produced 85% of its electricity demand from renewable energy

Congrats Germany! Credit: Pixabay.

Congrats, Germany! Image Credits: Pixabay.

For the most part of April 30, about 85% of Germany’s consumed electricity came from renewable energy sources such as solar, wind, or hydroelectric. According to a spokesman from the Agora Energiewende Initiative, a fortunate mix of sunny weather and strong winds in the south and north of the country, respectively, made this year’s Labour Day celebration even more eventful.

“Most of Germany’s coal-fired power stations were not even operating on Sunday, April 30th, with renewable sources accounting for 85 per cent of electricity across the country,” Patrick Graichen of Agora Energiewende Initiative said in a statement. “Nuclear power sources, which are planned to be completely phased out by 2022, were also severely reduced.”

Days like April 30th might turn from sensational into mundane by 2030 as the massive investment deployed by the German federal government steadily accrue energy dividends. By 2050, there will be no more energy derived from fossil fuels in Germany, if the government’s Energiewende initiative is to become successful. In other words, you won’t be able to call solar or wind alternative energy sources in Germany — they will be the energy sources. Even on uneventful days, Germany is still able to deliver 41% of its consumed electricity from renewables for the whole month of March.

Another recent development that lends confidence such a scenario is possible was last week’s announcement of the final bid for one of the world’s first subsidy-free offshore wind projects. Far exceeding everyone’s expectations, a company called DONG Energy was awarded the right to build three offshore wind projects in the German North Sea for an average of 0.44 cents per kilowatt hour. Again, that’s without any kind of government subsidies.

Germany is not the only European nation trying to wean itself from nonrenewable energy sources. On April 21st, for the first time since the Industrial Revolution, the United Kingdom went a whole day without coal-fired energy, though truth be told the current cabinet is not very fond of renewables. 

Atrioventricular node with macrophages.

Macrophages conduct electricity through the heart to keep it beating properly

Macrophages seem to not only help keep the body safe and clean but also make sure it stays very much alive by helping the mammalian heart beat in rhythm, new research reveals.

Colorized scanning electron micrograph of a macrophage.
Image credits NIAID / Flickr.

They’re the champion eaters of our bodies, gulping up pathogens and waste wherever they find them — they’re the macrophages. These white cells play a central part in our immune systems, for which we’re all thankful. But they may play a much more immediately vital role for us than we’ve suspected. Researchers from the Massachusetts General Hospital have discovered that these cells play a central part in regulating cardiac activity by conducting electrical signals through the heart.

“This work opens up a completely new view on electrophysiology; now, we have a new cell type on the map that is involved in conduction,” says senior author Matthias Nahrendorf, a systems biologist at Massachusetts General Hospital, Harvard Medical School.

“Macrophages are famous for sensing their environment and changing their phenotype very drastically, so you can think about a situation where there is inflammation in the heart that may alter conduction, and we now need to look at whether these cells are causally involved in conduction abnormalities.”

Researchers have known for some time now that macrophages can be found in and around hearts battling an infection — cause that’s what they do. But Nahrendorf team found that they still hang around in healthy hearts, in much greater numbers than would be required for simple maintenance or defense. So he and his team set out to understand why.

After performing MRI and electrocardiogram studies on model depleted of macrophages, the team found that the heart was arrhythmic and beat too slowly. By analyzing the heart tissue of a healthy mouse, they found that there’s a high density of macrophage cells at atrioventricular node, which carries electricity from the atria to the heart’s ventricles.

Working with David Milan and Patrick Ellinor, both electrophysiologists at Massachusetts General Hospital, the researchers found that the macrophages extend their membranes between cardiac cells and create pores, known as gap junctions, for electricity to flow through. This helps prepare the heart’s conducting cells (the ‘wiring’) for the next burst of electricity — allowing them to maintain a fast contraction rhythm.

Atrioventricular node with macrophages.

Cardiomyocytes (heart muscle cell, red) densely interspersed with macrophages (green).
Image credits Maarten Hulsmans / Matthias Nahrendorf.

“When we got the first patch clamp data that showed the macrophages in contact with cardiomyoctes were rhythmically depolarizing, that was the moment I realized they weren’t insulating, but actually helping to conduct,” Nahrendorf says.

“This work was very exciting because it was an example of how team science can help to connect fields that are traditionally separated — in this case, immunology and electrophysiology.”

The researchers say that the next step is to see whether macrophages have a hand to play in common conduction abnormalities in the heart. There are potential ties between macrophages and anti-inflammatory drugs, which are widely reported to help with heart disease. If macrophages do play a role in disease, the researchers say it can open up a new line of therapeutics, as these immune cells naturally consume foreign molecules in their presence and are easy to target as a result.

The full paper “Macrophages Facilitate Electrical Conduction in the Heart” has been published in the journal Cell.

The combined capacity of the renewable energy sector overtakes that of coal

An International Energy Agency report says global renewable-to-electricity capacity has overtaken coal, with the potential to supply up to 31% of the world’s energy.

Image credits Renan Deuter / Pixabay.

There was a huge boom of renewable energy in 2015, with some 153 GW (gigawatts) of new capacity installed. Renewable sources collectively accounted for more than half the global increase in power capacity. Much of this growth (40%) came from China‘s expansion of solar and offshore wind energy. The numbers presented by the IEA are quite impressive — the report says that half a million new solar panels were installed every day this year, and two turbines were installed every hour in China.

With this push, renewable energy capacity has overcome that of coal with 1,985 GW (about 31% of global power capacity) compared to 1,951 GW, the IEA said. Which is just swell.

But it’s important to note that the report looks at power capacity rather than output, so it’s a question of how much power could be produced, not how much is actually being churned out. That number is still significantly lower than coal, with renewables supplying roughly 23% of global production, compared to 40% from coal. Renewables, for the most part, are intermittent — they can’t produce at their full capacity all the time. These plants need winds or sunshine, but coal can be burned around the clock.

Still, it’s a historic development.

“We are witnessing a transformation of global power markets led by renewables,” said IEA’s Executive Director Fatih Birol.

All this increase was made possible by “impressive” cost reductions for onshore wind and solar, which would have been “unthinkable just five years ago”. The IEA expects this trend to continue, prompting the agency to increase its forecasted renewable capacity increase for the future. They expect an extra 825 GW to be built by 2021, a 13% increase on their forecast one year ago. This should bring renewables’ share in the global electricity balance to 28% by 2021, “rapidly closing the gap with coal” the IEA said. Generation from renewables is expected to exceed 7600 TWh by that year — equivalent to the total electricity generation of the United States and the European Union put together today.

Solar and wind are expected to be the main areas of growth, and the IEA expects they will account for three-quarters of new capacity. Hydro, which is now one of the largest sources of renewable energy, will continue to grow but at a slower rate than before. Some 61% of installed renewable capacity and 71% of renewable power output came from hydroelectric sources, according to the IEA. Wind power accounted for 15% of renewable output, bioenergy 8%, and solar 4%.

4% of output, 100% of the bling.
Ivanpah Solar Power Plant. Image credits Gregg Tavares / Flickr.

Governments will have an important part to play as well, as the renewable sector’s growth needs “policies aimed at enhancing energy security and sustainability” to keep its momentum. The report mentions decisions to provide financial incentives for using renewable power as a factor in this year’s growth, such as the extended tax credits in US. China, India, and Mexico have also introduced policy which has helped expand the sector.

“Growth is anticipated to be increasingly concentrated in emerging and developing economies, with Asia taking the centre stage,” Birol added. “In the next five years, the People’s Republic of China and India alone will account for almost half of global renewable capacity additions.”

The report says that while renewables are taking on a much bigger role than previously expected, there’s still room for more. Besides electricity production, renewables haven’t made much progress. In transport and heating “renewables penetration […] remains slow”, the report says. To limit climate change, stronger decarbonisation rates are needed which means we’ll have to work on bringing renewables “in all three sectors: power, transport, and heat”.

We’ll soon be able to hack our nerves into controlling diseases

A novel treatment method, which involves applying an electrical current to nerve cells, could help treat a wide range of conditions, from diabetes to arthritis, according to medical company Galvani Bioelectronics. With backing from GSK and Verily Life Sciences, Galvani hopes to bring their technique within seven years.

“Neuron” sculpture by Roxy Paine.
Image credits Christopher Neugebauer / Flickr.

During animal trials, Galvani researchers attached electrodes housed in tiny silicone cuffs around nerves and used to control the messages it carries. During one set of tests, the results suggested that the method could be used to treat type-2 diabetes, a metabolic disorder in which the body becomes resistant to insulin and produces too little of the hormone.

The team focused on a cluster of nerves in the animals’ necks near the main artery, which serve to check sugar an insulin hormone levels in the blood. They feed information to the brain, which in turn sends instructions to raise or lower these concentrations.

“The neural signatures in the nerve increase in type 2-diabetes,” said GSK vice-president of bioelectronics Kris Famm for BBC News. “By blocking those neural signals in diabetic rats, you see the sensitivity of the body to insulin is restored.”

And the applications don’t stop there.

“It isn’t just a one-trick-pony, it is something that if we get it right could have a new class of therapies on our hands,” Mr Famm said.

He also added that we’ve only begun “scratching the surface” when it comes to understanding how each nerve signal affects our body. We don’t even know if it’s just an issue of turning a nerve on or off, or if the signal’s volume and rhythm make a difference. And even if the approach works theoretically, a huge amount of effort will be needed to make the technology practical. So don’t expect your doctor to suggest it anytime too soon.

But once it becomes available, the electrode kits will be miniaturized and customizable to different pairs of nerves, durable enough to survive in your body for extended periods of time, and powered by efficient batteries — so kind of like pacemakers, but for nerves. So when will they become available?

“In 10 to 20 years I think there will be a set of these miniaturised precision therapies that will be available for you and me when we go to a doctor,” Dr Famm said.

“Bioelectronic medicine is a new area of therapeutic exploration, and we know that success will require the confluence of deep disease biology expertise and new highly miniaturised technologies,” added Verily chief technology officer Brian Otis.

“This partnership provides an opportunity to further Verily’s mission by deploying our focused expertise in low power, miniaturised therapeutics and our data analytics engine to potentially address many disease areas with greater precision with the goal of improving outcomes.”

Origami battery that runs on a few drops of water could revolutionize biosensors

An engineer from Binghamton University, State University of New York designed a new disposable battery that could power biosensors and other small devices in areas where conventional batteries are just too expensive. The battery only uses one drop of dirty water to generate energy. But the best part — it folds up like an origami ninja star.

Image credit: Jonathan Cohen/Binghamton University.

Seokheun Choi, assistant professor of computer and electrical engineering at Binghamton University, working with two of his students developed the new device that’s powered by the bacteria found in dirty water. This isn’t Choi’s first origami battery — his first design was shaped like a matchbox and consisted of four modules stacked together. The star version is made out of eight small batteries connected in a series, measures in at around 6.35 centimeters (2.5 inches) wide and has a better power output and increased voltage than the first one.

“Last time, it was a proof of concept. The power density was in the nanowatt range,” said Choi. “This time, we increased it to the microwatt range. We can light an LED for about 20 minutes or power other types of biosensors.”

Paper-based biosensors are currently used for pregnancy and HIV tests, but their sensitivity is limited says Choi. His battery could allow these sensors to employ fluorescent or electrochemical biosensors with a much better accuracy, even in developing countries.

“Commercially available batteries are too wasteful and expensive for the field,” he said. “Ultimately, I’d like to develop instant, disposable, accessible bio-batteries for use in resource-limited regions.”

The battery unfolds into a star with one inlet at its center and the electrical contacts at the points of each side. After adding a few drops of dirty water on the inlet and the device can be opened into a Frisbee-like shape, allowing each of the eight fuel cells to function. Each module is a sandwich of five functional layers with its own anode, proton exchange membrane and air-cathode.

While Choi’s first battery could be produced for about 5 US cents, the star is a bit more expensive — roughly 70 US cents. This is because the battery is also made with carbon cloth for the anode and copper tape in addition to the filter paper. The team plans to produce a fully paper-based device that has the power density of the new design with lower price tag.

Georgetown University team found you can literally zap creativity into your brain

Electrically stimulating the frontopolar cortex can enhance creativity, a new study from Georgetown University found.

Image credits aboutmodafinil.com (Creative Commons)

We tend to think of creativity as something you’re either born with or you’re not; that some people are just wired to be artists while others couldn’t paint to save their life. But this trait stems from your brain, and psychology professor Adam Green, Dr. Peter Turkeltaub from Georgetown University Medical Center (GUMC) and their team found that this organ can be coaxed into thinking more creatively.

“We found that the individuals who were most able to ramp up activity in a region at the far front of the brain, called the frontopolar cortex, were the ones most able to ramp up the creativity of the connections they formed,” Green explains. “Since ramping up activity in frontopolar cortex appeared to support a natural boost in creative thinking, we predicted that stimulating activity in this brain region would facilitate this boost, allowing people to reach higher creative heights.”

And it worked; by stimulating test subjects’ brains using tDCS (transcranial direct current stimulation) in combination with verbal cues, the participants could be made to think more creatively. Then the tDCS was focused on the frontopolar cortex, subjects formed more creative analogical connections between sets of words the researchers gave them to use. They also thought of more and more creative associations between these words.

“This work is a departure from traditional research that treats creativity as a static trait,” Green adds. “Instead, we focused on creativity as a dynamic state that can change quickly within an individual when they ‘put their thinking cap on.’ ”

“The findings of this study offer the new suggestion that giving individuals a “zap” of electrical stimulation can enhance the brain’s natural thinking cap boost in creativity,” he concludes.

The researchers write that their results offer “novel evidence” that tDCS can be used to enhance “conscious augmentation of creativity elicited by cognitive intervention” and extends the known boundaries of tDCS enhancement “to analogical reasoning, a form of creative intelligence that is a powerful engine for innovation.”

Dr. Turkletaub, a cognitive neurologist with the GMUC, hopes that their method of brain stimulation used in conjunction with verbal cues will one day be used to help people with brain disorders.

“People with speech and language difficulties often can’t find or produce the words they need,” he explains. “Enhancing creative analogical reasoning might allow them to find alternate ways of expressing their ideas using different words, gestures, or other approaches to convey a similar meaning.”

Electrical brain stimulation has also been shown to improve learning. Still, Turkeltaub and Green caution that while their results show promise, “it is important to be cautious about applications of tDCS.” This method’s full effects on brain function are still unknown, and experimental data gathered up to know needs further replication before researchers can safely apply it.

“Any effort to use electric current for stimulating the brain outside the laboratory or clinic could be dangerous and should be strongly discouraged,” Green cautioned.

The full paper, titled “Thinking Cap Plus Thinking Zap: tDCS of Frontopolar Cortex Improves Creative Analogical Reasoning and Facilitates Conscious Augmentation of State Creativity in Verb Generation” has been published online in the journal Cerebral Cortex and can be read here..

Longannet Power Station. Image: Alan Murray-Rust // licensed for re-use.

After 115 years of history, Scotland closes its very last coal-fired plant

The largest and last coal-fired plant in operation in Scotland was officially shut down, marking an end for an 115-years-long history of burning coal in the country.

Longannet Power Station. Image: Alan Murray-Rust // licensed for re-use.

Longannet Power Station. Image: Alan Murray-Rust // licensed for re-use.

Officials, journalists and former workers crowded the control room of the Longannet power station to say their goodbyes. Over the decades, the plant has served Scotland well and up until its last days it still provided a quarter of all Scottish homes with electricity. It was also responsible for a fifth of the country’s carbon emissions. Regulations, carbon taxes and expensive maintenance prompted Scottish Power, which owns Longannet, to close down the plant. “Ok, here we go,” said one engineer before pressing a big red button that discontinued the turbines.

Taking over from Longannet will be nuclear and gas, helped by the booming renewable energy industry. Home to 5 million people, Scotland generates enough wind power to supply 33% of its residents’ energy needs. It’s growing fast too. While the rest of the UK and much of Europe are slowing down their renewable energy implementation, Scotland doubled its wind power in only one year, as of 2015. The country aims to become 100% renewable energy power by 2020 — that’s only four years from now!

Solar panels are not to be neglected either, although weather conditions largely favor wind turbines. “Sunshine generated more than four-fifths of the electricity and hot water needs of homes fitted with solar panels,” said WWF Scotland.

“Coal has long been the dominant force in Scotland’s electricity generation fleet, but the closure of Longannet signals the end of an era,” Hugh Finlay, generation director at Scottish Power, told the Guardian.

“For a country which virtually invented the Industrial Revolution, this is a hugely significant step, marking the end of coal and the beginning of the end for fossil fuels in Scotland,” Richard Dixon, Director of Friends of the Earth Scotland, said in a statement.

Amber Rudd, the UK’s Secretary of Energy and Climate Change, said last year that Britain will  replace all coal fired plants with gas. All UK coal-fired power plants will shut down by 2025.

via Think Progress.

This is how one French power plant produces electricity using cheese

The town of Albertville in southeastern France has begun using cheese to generate electricity. Their power plant, build in the Savoie region, uses a byproduct of the local Beaufort cheese manufacturies as the base for its biogas power generation system.

Ahhh, cheese. Truly, a tragically under-appreciated food. Is there any meal it cannot make wholesome with its creamy bliss? Is there anything that cheese cannot do? The answer to the last one is most likely “yes” but the French seem set on turning it into a definite “no.” Not content with enjoying cheese only with their crackers and wine, the people of Albertville in France have now found a way to include dairy in their power grid.

Beaufort cheese.
Image via telegraph

The dairy plant, opened in October last year, uses the skimmed whey left over from the process of making Beaufort cheese. Mixing it with cultures of bacteria, the whey is left to ferment, producing a mixture of methane and carbon dioxide — in essence, biogas. The gas is then fed through an engine that heats water to 90 degrees Celsius, and the steam used to generate electricity.

“Whey is our fuel,” said François Decker of Valbio, the company that designed and built the cheesy station.

“It’s quite simply the same as the ingredient in natural yogurt.”

The plant will produce about 2.8 million kilowatt-hours (kWh) per year, enough electricity to supply a community of 1,500 people, Mr Decker told Le Parisien newspaper.

This isn’t Valbio’s first cheese-to-power station, but it is one of the largest. The company built its first prototype plant 10 years ago to be used by a cheese-making abbey where monks have kept this trade since the 12th century. About 20 other small-scale plants have been built in France, other European countries and Canada. More units are planned in Australia, Italy, Brazil and Uruguay.

Cream, the other by-product of Beaufort cheese-making is also reused for ricotta and serac cheese, butter, and protein powder.

An atomically thin material, molybdenum disulfide (MoS2), shown, could be the basis for unique electric generator and mechanosensation devices that are optically transparent, extremely light, and very bendable and stretchable. —Image courtesy of Rob Felt/Georgia Tech

This electric generator is only a few atoms thin

Researchers from Columbia Engineering and the Georgia Institute of Technology report the first experimental proof of piezoelectricity and the piezotronic effect in an atomically thin material, molybdenum disulfide (MoS2). This makes it the thinnest electrical generator in the world. The resulting generator is optically transparent, extremely light weight, as well as very bendable and stretchable. In the future, such generators could be used to power extremely tiny devices harnessing energy from the environment, be them remote sensors or nanotech that travels through your bloodstream.

The world’s thinnest electrical generator

Positive and negative polarized charges are squeezed from a single layer of atoms, as it is being stretched. —Image courtesy of Lei Wang/Columbia Engineering

Positive and negative polarized charges are squeezed from a single layer of atoms, as it is being stretched.
—Image courtesy of Lei Wang/Columbia Engineering

Piezoelectricity is a well documented form of energy conversion  in which stretching or compressing a material causes it to generate an electrical voltage, or viceversa — an electrical current is applied to cause expansion or contraction in a material. This effect has been harnessed for various applications, some more practical than others, like a notebook that can be powered by typing (a piezoelectric transducer converts the pressure used to press the keys into electricity). This is the first time, however, that piezoelectricity has been demonstrated at the scale of only a few atoms of thickness.

“This material—just a single layer of atoms—could be made as a wearable device, perhaps integrated into clothing, to convert energy from your body movement to electricity and power wearable sensors or medical devices, or perhaps supply enough energy to charge your cell phone in your pocket,” says James Hone, professor of mechanical engineering at Columbia and co-leader of the research.

“Proof of the piezoelectric effect and piezotronic effect adds new functionalities to these two-dimensional materials,” says Zhong Lin Wang, Regents’ Professor in Georgia Tech’s School of Materials Science and Engineering and a co-leader of the research. “The materials community is excited about molybdenum disulfide, and demonstrating the piezoelectric effect in it adds a new facet to the material.”

Generating power in 2-D

An atomically thin material, molybdenum disulfide (MoS2), shown, could be the basis for unique electric generator and mechanosensation devices that are optically transparent, extremely light, and very bendable and stretchable. —Image courtesy of Rob Felt/Georgia Tech

An atomically thin material, molybdenum disulfide (MoS2), shown, could be the basis for unique electric generator and mechanosensation devices that are optically transparent, extremely light, and very bendable and stretchable.
—Image courtesy of Rob Felt/Georgia Tech

You might remember Hone as being part of a research group that proved in 2008 that graphene — a 2-D form of carbon arranged in a hexagon geometry — is the strongest material in the world. Since then, Hone and colleagues have been exploring the novel properties of 2D materials like graphene and MoS2 as they are stretched and compressed.

Because MoS2 is highly polar, an even number of layers cancels out the piezoelectric effect, so if the material is to be effective at generating current an odd number of layers need to be used and flexed in the proper direction. The fact that  the material’s crystalline structure also is piezoelectric in only certain crystalline orientations made matters even more challenging.

Hone’s team placed thin flakes of MoS2 on flexible plastic substrates, then  patterned metal electrodes onto the flakes.  Wang’s group installed measurement electrodes on samples provided by Hone’s group, then measured current flows as the samples were mechanically deformed. As the material was deformed, voltage and current outputs were measured, as seen in the paper published in Nature.

“This is the first experimental work in this area and is an elegant example of how the world becomes different when the size of material shrinks to the scale of a single atom,” Hone adds. “With what we’re learning, we’re eager to build useful devices for all kinds of applications.”

A single monolayer flake strained by 0.53% generates a peak output of 15 mV and 20 pA, corresponding to a power density of 2 mW m−2 and a 5.08% mechanical-to-electrical energy conversion efficiency. Of course, for most applications this sort of power output is useless, but even a few milliwatts of power can sustain tiny micrometer devices. This study also reveals the piezotronic effect in two-dimensional materials for the first time and considering MoS2 is just one of a group of 2D semiconducting materials known as transition metal dichalcogenides, there’s no telling what kind of breakthrough can be achieved in the future once more materials are probed for piezoelectricity.

Advances in magnet technology could bring cheaper, modular fusion reactors from sci-fi to sci-reality in less than a decade

Advances in magnet technology have allowed MIT scientists to design a cheaper, more compact, modular and highly efficient fusion reactor that is efficient enough to use commercially. The era of clean, practically inexhaustible energy may be upon us in as little as a decade, scientists report.

MIT PhD candidate Brandon Sorbom holds REBCO superconducting tapes (left), enabling technology behind the ARC reactor.
When cooled to liquid nitrogen temperature, the superconducting tape can carry as much current as the large copper conductor on the right, enabling the construction of extremely high‑field magnets, which consume minimal amounts of power.
Photo: Jose‑Luis Olivares/MIT

The team used newly available rare-earth barium copper oxide (REBCO) superconducting tapes to produce high-magnetic field coils.

“[The implementation of these magnets] just ripples through the whole design,” says Dennis Whyte, professor of Nuclear Science and Engineering and director of MIT’s Plasma Science and Fusion Center. “It changes the whole thing.”

Bigger bang for your magnet

But how do magnets help us build a mini-star? Well, fusion reactors generate electricity by using the same physical process that powers stars. In such a reactor, two lighter atoms are mushed together to create heavier elements. And just like natural stars, they generate immensely hot plasma – a state of matter similar to an electrically charged gas.

The stronger magnets and the stronger magnetic fields they generate allow the plasma to be contained in a much smaller space than previously possible. This translates to less materials and space necessary to build the reactor, and less hours of work, meaning a cheaper, more affordable reactor.

The proposed reactor, using a tokamak (donut-ish) geometry is described in a paper in the journal Fusion Engineering and Design, co-authored by Whyte, PhD candidate Brandon Sorbom, and 11 others at MIT.

A cutaway view of the proposed ARC reactor. Thanks to powerful new magnet technology, the much smaller, less-expensive ARC reactor would deliver the same power output as a much larger reactor.
Illustration credits to the MIT ARC team

Power plant prototype

The basic concept of the reactor and its associated elements rely on well-tested and proven principles that have been developed over decades of study.

The new reactor is intended to allow basic research on fusion and to potentially function as a prototype power plant – that could produce significant quantities of power.

“The much higher magnetic field,” Sorbom says, “allows you to achieve much higher performance.”

The reactor uses hydrogen fusion to form helium, with enormous releases of energy. To sustain the reaction and make it energy efficient (to release more energy than the reaction consumes) the plasma has to be heated to temperatures hotter than the cores of stars. And here is where the new magnets come in handy – they trap the heated particles in the center of the tokamak.

Cutaway of the inner workings of the ITER reactor. Not much difference structurally in the tokamak, the increase in power comes from the magnets. Notice the solid cover over the reactor.
Image via nature

“Any increase in the magnetic field gives you a huge win,” Sorbom says.

This is because in a fusion reactor, changing the strength of the magnetic field has a dramatic effect on the reaction: available fusion power increases to the fourth power of the increase in the magnetic field. Doubling the field would thus produce a 16-fold increase in the power generated by the device.

Ten times more power

The new magnets do not quite produce a doubling of the field strength, but they are strong enough to increase the power generation of the reactor ten times over previously used superconducting technology, the study says. This opens up the path for a series of improvements to be done to the standard design of the reactor.

The world’s most powerful planned fusion reactor, a huge device under construction in France called ITER, is expected to cost around US$ 40 billion. This device was designed and put into production before the new superconductors became available. Sorbom and the MIT team believe that their new design would produce about the same power as the french reactor, while being only half the diameter, cost but a fraction of its price and being faster to construct.

But despite the difference in size and magnetic field strength, the proposed reactor, called ARC, is based on “exactly the same physics” as ITER, Whyte says.

“We’re not extrapolating to some brand-new regime,” he adds.

The team also plans to include a method for removing the fusion core from the reactor without having to dismantle the entire device. Being able to do this would lend well to research aimed at further improving the system by using different materials or designs of its core to improve performance.

In addition, as with ITER, the new superconducting magnets would enable the reactor to operate in a sustained way, producing a steady power output, unlike today’s experimental reactors that can only operate for a few seconds at a time without overheating of copper coils.

Molten core and liquid cover

Another key breakthrough the design of the reactor brings is that it replaces the blanket of solid materials that surrounds the fusion chamber with a liquid material, that can be easily circulated and replaced. This curbs operating costs associated with replacement of the materials that degrade over time.

“It’s an extremely harsh environment for [solid] materials,” Whyte says, so replacing those materials with a liquid could be a major advantage.

In its current state, the reactor should be capable of producing about three times as much electricity as is needed to keep the reaction going. Sorbom says that the design could probably be improved and fine-tuned to crank up to about five or six times that much power. So far, no completed fusion reactor has produced energy (well they did, but they use more juice than they make) so the kind of net energy production ARC is expected to deliver would be a major breakthrough in fusion technology, the team says. They estimate that the design should be able to produce electricity for about 100,000 people.

“Fusion energy is certain to be the most important source of electricity on earth in the 22nd century, but we need it much sooner than that to avoid catastrophic global warming,” says David Kingham, CEO of Tokamak Energy Ltd. in the UK, who was not connected with this research. “This paper shows a good way to make quicker progress,” he says.

The MIT research, Kingham says, “shows that going to higher magnetic fields, an MIT speciality, can lead to much smaller (and hence cheaper and quicker-to-build) devices.” The work is of “exceptional quality,” he says; “the next step … would be to refine the design and work out more of the engineering details, but already the work should be catching the attention of policy makers, philanthropists and private investors.”

The research was supported by the U.S. Department of Energy and the National Science Foundation.

Dutch Company Harvests Electricity From Living Plants, Powering Street Lights, Cell Phones and Wi-fi

Forget potato clocks – this is the real deal. Plant-e, a start-up company in the Netherlands created promising new technology which harvest electricity from plants. So far this month, more than 300 LED lights were illuminated by the Dutch company, in a promising proof-of-concept. They also demonstrated that they could power up cell phones and Wi-Fis.

Generating electricity from thin air sounds like a dream come troue, but that’s exactly what Marjolein Helder, the CEO and co-founder of Plant-e claims her company can do. They debuted the “Starry Sky” project in November 2014 at an old ammunition site called HAMbrug, near Amsterdam, and are using the same technique close to their headquarters in Wagenigen.

Using plants to extract energy is not exactly a novel idea – potato clocks have been the shock of science fairs for decades, but from what I found, this is the first project that uses plants to harvest energy without actually damaging them. But while adding this technology in places like the Netherlands is cool and will generate clean energy, what they really want to do is install it in existing wetlands and rice paddies where electricity can be generated on a larger scale. This could give power to some of the world’s poorest places.

At the moment though, the main problem is the quantity of energy which it generates. Simply put – it’s not enough. But researchers working on the technology are optimistic they will be able to improve it. Ramaraja Ramasamy, an adjunct professor at the University of Georgia College of Engineering explains:

“It’s not making enough energy to have any reliable commercial product. That doesn’t mean that it will not be. We are too early in the research,” Ramasamy explained. “If I come to you and say, ‘Do you want to power that 100-watt bulb?’ You probably need an acre of land and dirt to get the electricity from. Is that feasible? No.”

If we put some numbers down, a one-square-meter garden should be able to produce 28 kilowatt-hours per year. According to the US Energy Information Administration, the average American house required approximately 10,837 kilowatt-hours in 2012. But a Dutch house requires about three time less energy, and a house in rural China or India – even less. That means that while you could barely power up an American house with a big backyard (which is pretty good in itself), you could power up entire villages in the vecinity of rice paddies.

This would require the company using existing wetlands to generate electricity – something which they are working on, but have not yet managed to achieve. The system would involve placing a tube horizontally below the surface of a wetland, peat bog, mangrove, rice paddy, or river delta, and use the same process as the modular system. The problem they are facing now however, is financing.

“Modular systems are interesting, but you can only scale up to a certain size because it’s pretty labor- and material-intensive,” Helder said. “A tubular system can just be rolled out through the field and it just works because the plants are already there. So for the longer term, for the really large scale, that’s much more interesting.”

This tubular system is at least a couple of years away from actually becoming a reality, but there are some good prospects. Meanwhile, the company is already selling products which enable you to harvest energy from plants.

What do you think, is this technology really innovative and full of potential, or is creative, but not practical at all?

Electric Mind Control: How the Electric Eel Dominates its Prey

The Electric Eel, a scaleless fish from the Amazon possesses an electroshock system very similar to a Taser. Not only can it stun its prey with the shock, but it can also make it twitch involuntarily, revealing its position.

The electric eel can send out bursts of up to 600 volts. Image via Wiki Commons.

The electric eel is able to generate powerful electric shocks of up to 650 volts, which it uses not only for attack and self defense, but also to communicate with others and sense the environment. Researchers have known for a while that they can also generate electricity to immobilize their prey and prevent it from escaping, but a new study conducted by researchers from Vanderbilt University finally explains exactly how this mechanism works; the research also showed that the electric eels can also remote control the minds of their prey, making them twitch and reveal their position through electric shocks. Yep that’s right – even though we’ve known about the eel for a very long time, no one really figured out how they’re able to work their electrical magic – until now.

“It’s really a beautiful piece of work,” says biologist Jason Gallant of Michigan State University in East Lansing, who studies the evolution of electric fish but was not involved in the new research. “These findings were a total surprise to me.”

Professor of Biological Sciences Kenneth Catania first noticed that the eel is very fast – being able to attack and swallow a worm or some other small prey in a tenth of a second. He quickly understood that if he wants to study their actions in detail, he will need some high-speed photography. With this set-up, he also studied their electrical abilities.

Catania recorded three different kinds of electrical discharges from the eels: low voltage discharges used for navigation and environmental sensing, short sequences of two or three high-voltage millisecond pulses (called doublets and triplets) used for hunting and lengthy high voltage, high frequency pulses used for self defense or for capturing the prey. He found that following the hunting zap, the prey is completely immobilized for a short period of time:

“It’s amazing. The eel can totally inactivate its prey in just three milliseconds. The fish are completely paralyzed,” said Catania.

Naturally, these initial observations led to other questions – and most importantly, how do they do it? Nobody actually figured out how the electric eel can stun its target.

“I have some friends in law enforcement, so I was familiar with how a Taser works,” said Catania. “And I was struck by the similarity between the eel’s volley and a Taser discharge. A Taser delivers 19 high-voltage pulses per second while the electric eel produces 400 pulses per second.”

The way the Taser works is pretty simple – it sends strong bursts of electricity to the muscles, overriding the nerves controlling the muscles and making them contract – exactly the way the eel does it. With that question answered, a single mystery remained.

The electric eel is a nocturnal animal, yet it has pretty bad eye sight; how then does it detect its prey? Catania had a pretty good hunch, and set out to test it. As it turns out, his hunch was correct – the fish sends out a very specific electric signal which produces a very rapid contraction in the muscles of its prey. This gives away the position of the prey, basically through remote control.

“Normally, you or I or any other animal can’t cause all of the muscles in our body to contract at the same time. However, that is just what the eel can cause with this signal,” Catania said.

It’s still not clear how the eel evolved this way… but this remarkable creature definitely has some unique weapons in its arsenal.

“If you take a step back and think about it, what the eel can do is extremely remarkable,” said Catania. “It can use its electrical system to take remote control of its prey’s body. If a fish is hiding nearby, the eel can force it to twitch, giving away its location, and if the eel is ready to capture a fish, it can paralyze its muscles so it can’t escape.”

Journal Reference: Kenneth Catania. The shocking predatory strike of the electric eelScience, DOI: 10.1126/science.1260807.


Thin metasurface absorbs sound near perfectly, while producing electricity at the same time


Image: Nature

Researchers at the Hong Kong University of Science and Technology have created a thin metamaterial surface that is capable of absorbing nearly all of the acoustic energy (sound).  Unlike conventional sound absorbing material that is sometimes only effective when meters thick, the metasurface is deeply “subwavelength” and therefore much thinner. There’s a catch though: the system has been demonstrated for near perfect sound absorption when the system is tuned to a particular frequency.

Silence: an almost perfect sound absorber

Sound absorption materials are usually manufactured with the wavelength of the desired frequency to be absorbed in mind, which for human hearing ranges from 17 meters to 17 millimeters for low to high frequencies respectively. This is why in a studio the mid and high frequencies are easily damped, but you can still hear low frequencies outside.

[SEE ALSO] Intelligent shock absorber dampens vibrations and generates power

The new metamaterial, called a “decorated membrane resonator” (DMR), works different though [cite]doi:10.1038/nmat3994[/cite]. It’s made out of  tiny drum membrane embedded in and coupled to a solid support, in the center of which is a platelet. For their demonstration, the researchers used a 9 cm membrane, only 0.2 mm thick, holding a 2 cm platelet in diameter. For the harmonics of the metasurface to correspond to the sound’s wavelengths, the membrane needs to have a very low elastic modulus. A reflecting backing then sandwiches a sealed gas layer.

The metasurface exhibits resonance at audible wavelengths such that there is near total absorption of sound, and dissipation of the energy along the lossy membrane.

The system was shown to have “impedance matching” to the airborne sound waves. This makes the metasurface an excellent energy absorber that doesn’t reflect waves coming from a particular wavelength. This high impedance is powered by the sandwiched gas, as well as the reflective backing surface.

[RELATED] How sound frequencies affects taste

Absorbing sound and generating power at the same time

What’s maybe most striking about the setup is that the vibrations induced in the platelet-membrane system can be coupled to energy generation, with a sound-to-electrical conversion efficiency of 23%. A whole DMR array coupled for various frequencies could then be used to power low-voltage devices, besides dampening sound.

Of course, there’s a catch. The system is tuned to work only for a particular frequency. More than one layer would be needed to catch multiple frequencies or a single layer must contain a number of differently-sized DMRs. Sure, the DMR will prove very useful for applications where a targeted and well-known frequency needs to be absorbed, but the system doesn’t sound that appealing for studios or even highway walls that dampen the noise around residences – it would be too expensive. To set the resonant frequency (the frequency we’re looking to dampen), all you need to do is vary the thickness of the gas layer.

Illustration: niemer.deviantart.com

People prefer getting an electric shock than being left alone with their thoughts

Illustration: niemer.deviantart.com

Illustration: niemer.deviantart.com

Here’s a weird study. A group of psychologists at University of Virginia introduced men and women alone in a room for fifteen minutes with nothing to distract them. No TV, no phone, no internet, no books, nothing but their thoughts… and a zapping device that sent a mild electric shock. Conclusion: most people would rather kill their time receiving electrical shocks than being left alone with their thoughts. It’s the kind of study that shocks you (sorry), because it tells an ordinary truth – we’re scared of being left alone with ourselves because people have become so disconnected with their inner selves, that they would gladly take on any distraction as long as it spares them the misery of confronting themselves.

Ok, so they were just curious. I’d zap myself too if I was alone in a room with only a zap button. Common, who wouldn’t? In the researchers’ defense, however, the study took the necessary precaution of phasing curiosity out by zapping each participant before they entered the room of solitary doom. So, each of the students involved in the study knew beforehand what happened if they got electrocuted by the device containing a 9 V battery. And they didn’t do this once. On average, participants received electrical shocks seven times. One man actually gave himself 190 electric shocks over a period of 15 minutes. Serious issues.

Wait, there’s more. Apparently, men have bigger issues with themselves than women. Out of 24 women, only six decided to shock themselves, but 12 out of the 18 thought they couldn’t miss it. The guy who zapped himself 190 times was only counted once, just so you know. The researchers hypothesize that men are more willing to take risks for the sake of a intense and complex experiences than women. Or they’re just stupid.

The results are a bit limited however. The sample size is really low, and all the people involved in the study are students at University of Virginia. There are also some psychological caveats that need to be factored out somehow, which researchers didn’t do. For instance, the participants knew they were watched, and this might have introduced unnecessary psychological stress. Heck, most of the participants would have rather masturbated probably than become electrocuted, which also defeats the purpose of being alone with your thoughts, but alas. I would love to see the results of a replicated study with a far broader sample size and demographic.

The findings appeared in the journal Science.


Power lines may be absolutely terryfing animals and disrupt herding


High voltage power lines aren’t quite the safest places to be around, especially if you’re a large animal or bird and touch two different conductors, thus creating a voltage difference which kills on the spot. Apparently, though, not too many animals wonder near power lines. Roads are known animal traffic disruptors, but even power lines stretched across isolated portions where there aren’t any roads still keep animals away. A possible explanation for this is that the electricity flowing through power lines looks terryfing to them, thus discouraging the animals from coming in the vicinity. If this is found true, it could potentially have important implications from an environmental perspective, as power lines should be designed to cross areas where there’s a low risk of disrupting herding paths and flock patterns.

Power lines may look scary to some humans too, but when some animals gaze them they see something much different. Researchers in Norway and the United Kingdom recently proposed that animals keep away from high voltage cables because of their ability to see ultraviolet light frequencies. This spectrum is totally invisible to humans, hower some animals, especially those that have developed nocturnal vision, can see it. These include critters like birds, rodents and some species of large mammals like raindeer. The scientists write:

“We suggest that in darkness these animals see power lines not as dim, passive structures but, rather, as lines of flickering light stretching across the terrain. This does not explain avoidance by daylight or when lines are not transmitting electricity … but it may be an example of classical conditioning in which the configuration of power lines is associated with events regarded as threatening.”

So what do these animals see? It’s impossible to undertand how they see it through their own eyes, but using cameras mounted with UV sensing one can get an idea. Basically, they should be seeing random flashing bands filled with flickering balls of light. This means that even in the dark, what to use humans is nothing but pitch black, power lines may look like alterating bands of light that could frighten them. The video below shot from a helicoper hovering over power lines gives you an example.

This suggests that it’s not noise or traffic that discourages animals coming too close, and thus disrupt habitats through the areas crossed by power lines, but something more suble and impernetrable to the human eye. The cables probably interfere with migration routes, breeding grounds, and grazing areas, which could fragment natural habitats and cause herds to shrink, and the ramifications this may pose to local ecosystems are just begining to be understood. For residents in Norway where a 86-mile-long power line through the northern part of the country is planed the research is of immediate interest. Already, local groups have voiced their disapproval of the project citing herding disruption.

The findings were reported in the journal Conservation Biology.