Tag Archives: turbine

Burbo Bank Turbine.

UK’s massive wind turbines are setting the course for a cheap-energy future

The UK can now boast to have the biggest wind turbines ever seen — no fewer than 32 of them at that. These massive installations are set to propel wind energy towards becoming the cheapest source of energy.

Burbo Bank Turbine.

Image credits Dong Energy.

There’s nothing little about the UK’s latest wind turbines. Taller than the London Eye, 34 of these metal giants were installed at the Burbo Bank wind farm seven kilometers from the Liverpool Bay area. Each stands 195 meters (640 ft) tall, some 53 meters (174 ft) taller than a standard turbine, and have a mammoth wingspan of 164 meters (538 ft).

Bigger is better

Which is all very good news if you’re a fan of cheap clean energy since, for wind turbines, size means efficiency. A single rotation of these beasts’ turbines is enough to power an average household for more than a day. They’re designed to stay in motion over 80% of the time, and at peak capacity, Burbo Bank can power 230,000 homes.

“They’re extremely powerful machines,” says Benj Sykes, UK manager Dong Energy, the offshore energy firm which operates Burbo.

“It’s got a very big rotor, it’s more efficient at catching energy from the wind over a wider range of wind speeds. They cut in at quite low wind speeds – four or five metres a second.”

You’d imagine something this huge would take a lot to build, but they’re actually more cost-efficient than their smaller counterparts. While their upfront installation costs — these include manufacturing costs, the cost of pouring their foundation on the sea floor, and plugging them into the grid — are comparable or higher, they churn out much more energy, sweetening the deal in the long run.

“The more power you can get out of each turbine, the more power you can get out of each foundation, out of each array cable, and so it drives the cost down across all of those elements,” Skyes says.

The biggest hurdle they’ve had to overcome, Skyes says, was getting the turbines out to sea. Dong Energy used a special “jack-up vessel” that can lift itself out of the water. The ship carried the turbine parts from Belfast to the Burbo Bank, and once there used its legs to rise up and lift the equipment in place using an onboard crane. Initially, the company needed 36 hours to install a turbine, but by the end of the project they got it down to one per day.

Burbo shows how efficient big turbines can become — pushing wind energy even closer to being the cheapest form of power generation around. So we’re bound to see even bigger turbines popping up in the future.

The proposed wind turbine will have two blades instead of the three usually employed. Credit: Pixabay.

World’s largest wind turbine will be taller than the Empire State Building

In wind energy, bigger is almost always better. With this in mind, six leading universities and institutions have banded together to design that world’s largest wind turbine yet. Standing at 500 meters (1,640 feet), the SUMR project will be about 57 meters taller than the iconic Empire State Building. The concept features two 200-meter (650-foot) turbine blades which are twice the size of an American football field.

The proposed wind turbine will have two blades instead of the three usually employed. Credit: Pixabay.

The proposed wind turbine will have two blades instead of the three usually employed. Credit: Pixabay.

Over the last two decades or so, wind turbines have become larger and larger. In the 1980s, the largest wind turbines had a rotor diameter of only a couple tens of meters. Today, land-based supply is dominated by turbines in the 1.5 and 2 MW range — enough to power 500 American homes — and typical wind farm towers stand around 70 meters tall. This dramatic evolution in size is no accident because power output depends on the rotor blades’ size and the wind turbine tower’s height.

The higher up the turbine is, the better the winds are and the more kinetic energy can be harvested. A taller structure can thus capture more energy. It also enables lengthier blades and a larger swept area — the circular area drawn by a blade’s rotation. Interestingly, a turbine’s power output doesn’t linearly increase with the blade’s size. Because the swept area is what matters, if a system’s blade length doubles, the power output can actually quadruple.

Wind turbine design and power output progression along the years. Credit Dong Energy.

Wind turbine design and power output progression over the years. Credit Dong Energy.

The mega-turbine

So, all of this explains why companies and universities are going for bigger, taller wind turbines — it just makes economic sense to do so. Eric Loth, the project leader of SUMR which is directly funded by the U.S. Department of Energy’s Advanced Research Projects Agency–Energy (ARPA–E), says his team wants to design a 50-megawatt turbine, with blades that span up to 200 meters long. If they can make it work, their resulting turbine would be around ten times more powerful than anything that came before it.

The team is led by the University of Virginia and includes Sandia National Laboratories and researchers from the University of Illinois, the University of Colorado, the Colorado School of Mines and the National Renewable Energy Laboratory. Corporate advisory partners include Dominion Resources, General Electric Co., Siemens AG and Vestas Wind Systems.

The current largest wind turbines in the world are housed outside Liverpool Bay where 32 gigantic structures dot the landscape, each 195 meters (640 ft.) tall and carrying 80-meter-long (262-foot-long) blades that can generate 8 megawatts of power. SUMR50 would be more than twice as tall. Its turbine structure would be fundamentally different too as it will be fitted with two blades instead of the usual three to lower the weight of the structure. Typically, cutting down the number of blades from three to two would lower efficiency but the team is compensating for the loss with an advanced aerodynamic design.

“Exascale turbines take advantage of economies of scale,” said Todd Griffith, lead blade designer on the project and technical lead for Sandia’s Offshore Wind Energy Program.

What the SUMR project could look like. Credit: Chao Qin

What the SUMR project could look like. Credit: Chao Qin

Like today’s biggest turbines built by Dong Energy, SUMR turbines are meant for offshore deployment, as much as 80 kilometers away from the coast, where winds are generally stronger and people can’t see or hear them.

“The U.S. has great offshore wind energy potential, but offshore installations are expensive, so larger turbines are needed to capture that energy at an affordable cost,” Griffith said.

At the same time, this makes the engineering effort even more challenging. Building a half-kilometer tall wind turbine that can withstand hurricanes doesn’t sound easy at all. Loth already has some safety features in mind. For instance, wind speeds above 80 to 95 km/h will trigger the shut down of the system causing the blades to bend away from the wind instead of resisting, somewhat akin to how palm trees withstand gushing winds. According to Sandia, “SUMR’s load-alignment is bio-inspired [….] The lightweight, segmented trunk approximates a series of cylindrical shells that bend in the wind while retaining segment stiffness.”

“At dangerous wind speeds, the blades are stowed and aligned with the wind direction, reducing the risk of damage. At lower wind speeds, the blades spread out more to maximize energy production.” Griffith said.

Todd Griffith shows a cross-section of a scaled down model of a 50-meter blade already in operation, which is part of the pathway to the 200-meter exascale turbines being planned under a DOE ARPA-E-funded program. Credit: Sandia.

Todd Griffith shows a cross-section of a scaled down model of a 50-meter blade already in operation, which is part of the pathway to the 200-meter exascale turbines being planned under a DOE ARPA-E-funded program. Credit: Sandia.

But there are also many other puzzling engineering problems that don’t yet have a complete solution. There are many reasons no one has built a turbine with 200-meter-long blades, one of them being it’s very difficult to put them together — and offshore, tens of miles away from the coast to boot. And while bigger is generally better for wind turbines, no one is really sure where the sweet spot is. Will SUMR50 have an optimal design?These questions and more are on everyone’s mind right now in Loth’s team.

They will learn more once they have a small-scale working prototype ready by the end of this summer. It will only be two meters in diameter so next year they’ll have a much larger version with two 20-meter-long blades to run tests in Colorado. These experiments will be crucial in establishing whether a 500-meter-tall turbine is worth the investment or the concept can be shelved as sub-optimal. It’s amazing to look back and reflect how much wind turbines have changed over the last 30 years though. Just like solar energy mega structures, today’s wind turbine design echoes rapid developments in renewable energy which, in the United States, has tripled its capacity in only nine short years. Steadily but surely, the word ‘alternative’ will stop to make sense for wind or solar — they will become the de factor energy sources soon enough despite the ‘best’ efforts of some people who wouldn’t like this to happen.


Flapping wind turbine mimics hummingbird to produce electricity


Artist impression of a field packed with hummingbird-like wind turbines. Credit: TYER WIND

Generating energy from wind can be very lucrative. In Denmark or Scotland, for instance, wind is no longer an alternative energy source — it is the energy source. Indeed, the industry has matured immensely, employing millions of people and operating hundreds of thousands of turbines. That’s not say there’s no room for experimentation, though. Right now, in Tunisia, the weirdest looking turbine is busy producing energy. Instead of catching gusts with a three-bladed boring turbine, this design uses the wind to make the turbine literally flap.

It’s a design inspired by the world’s only bird capable of hovering and backwards flight — the gorgeous hummingbird. According to Tyer Wind, the company behind the project, this turbine is comprised of two vertical axis wings made from carbon fiber, each 5.25 feet long. The two wings can sweep an area of nearly 12 square feet to convert kinetic energy into electricity. The turbine installed in Tunisia has a rated power output of 1 KW.

This is the first time the hummingbird’s flight dynamics have been mimicked by a mechanical device, the company stated.

“Million of years of natural selection have turned hummingbirds into some of the world’s most energetically efficient flyers. It has a unique morphology and kinematics that allows him to flap its wings between 50 and 200 times a second when in flight. Hummingbirds are the only group of birds with the ability to hover and to fly backwards. The motion of the Hummingbird wings (infinity in 3D) have intrigued many researches who have been struggling to mimic it,” Tyer Wind states on its website.

Tyer claims that this design “is a highly efficient wind converter”, according to in-house test. Central to its performance is its aerodynamic features which supposedly allow the turbine to generate work during both downstroke and upstroke.

Preliminary results suggest the hummingbird-turbine works as expected, performing well both in terms of power efficiency and aerodynamics. These results, however, haven’t been released publicly yet, Inhabitat reported, which can be a bit frustrating. Does it perform better or worse than conventional turbines? How worse or better? These are important questions which will hopefully be answered soon and verified by independent bodies. Until then, Tyer’s design looks like a promising design but it wouldn’t be the first ‘experiment’ to fail miserably.

Why the first, tiny offshore wind farm in the U.S. is a huge step forward

The U.S. has finally begun following Europe’s example in green energy with the country’s first offshore wind project, the Block Island Wind Farm, completed last week. While relatively tiny, the farm marks the start of a new American industry, and will feed power into New England’s electric grid.

Image credits Phil Hollman.

It has only five turbines and can power an estimated 17,000 homes — which isn’t much for a power plant of this type. But the inconspicuous Block Island Wind Farm is a U.S-first, and many hope that its example will lead to the creation of a new, cleaner energy industry in the country.

We’ve seen several European countries invest heavily in off-shore wind farms over the past few years, and for good reasons. Installing the turbines offshore is more expensive, but they can harvest the energy of the sea’s strong, steady winds. This means they can produce more power, and produce it more reliably, than their land-locked counterparts. There’s also the advantage of taking the turbines away from populated areas, limiting noise pollution and the risk of accidents.

But the U.S. never got its hands on a piece of this very profitable pie. While European countries were installing these machines by the thousands, proposals in the U.S. faltered due to a lack of expertise in the field (which drove installation costs up), opposition from locals who didn’t want their view of the ocean ruined by the turbines, and a murky legislation about the use of seafloor.

“People have been talking about offshore wind for decades in the United States, and I’ve seen the reaction — eyes roll,” said Jeffrey Grybowski in an interview on Block Island. “The attitude was, ‘It’s not going to happen; you guys can’t do it.’”

Jeffrey Grybowski, CEO of Deepwater Wind of Providence, R.I., has now proved that they can. With backing from the political leadership of Rhode Island, which took up the torch for this newly born industry ahead of bigger states like New York of Massachusetts, the company set up the Block Island Wind Farm.

They’ve also been helped by improving legislative conditions — starting from a law passed by Congress in 2005 and signed by President George W. Bush, the Obama administration has been clarifying the ground rules for off-shore turbine farms. They’ve also been leasing out large patches of ocean floor for wind-power development, so there are nearly two dozen such projects currently in development — setting the stage for the United States to dramatically expand on offshore wind.

Even at state level governments have begun making big pushes towards renewable power, driven by a growing sense of urgency regarding climate change. Gov. Andrew M. Cuomo of New York set a goal of drawing 50 percent of the state’s power from renewables by 2030, and the state will probably need large offshore wind farms to help achieve that. Gov. Charlie Baker of Massachusetts also signed a bill ordering the state’s utilities to develop contracts with offshore wind farms for an immense amount of power — 50 times the expected output of the Block Island Wind Farm. Other states, too, are looking to cash in on wind power and the Department of Energy believes that many thousands of these turbines could one day circle the United States coastline.

Right now, the focus in on the Northeast. There are a lot of power-hungry cities here so energy sells well, but there’s fierce opposition to building new power plants on land — thankfully, its coastlines have some of the world’s fiercest winds and the water stays relatively shallow for miles off shore so turbines can be installed where they won’t be seen from the beaches.

The Unites States might also have to profit from the extensive expertise others have on offshore wind turbines. The technology has been proved in Europe, with each turbine now costing up to $30 million to build, install and connect to the power grid. It’s a billion dollar industry, and the companies that install them have developed accordingly. Where European nations once used to promote wind farm by agreeing to sell the power at a premium price, they now use competitive bidding to drive down the cost of the projects. While installation will still be pricier than in Europe because local companies don’t have the technical base and the same know-how, the U.S. will still save a lot of money off of these falling costs — the Block Island turbines were built overseas by a division of General Electric and were installed by a ship from Norway, brought over at a cost of millions of dollars, with help from an American vessel.

The hude Fred Olsen Windcarrier helped install the turbines.
Image credits kees torn / Flickr.

However, if the plans laid down right now follow through, the costs will fall dramatically as domestic industry groups scale up to meet the demand. For the Block Island project, a company in Houma, La., won the contract to build the metal foundations in the water, and several Gulf Coast businesses specialized in offshore oil structures see wind power in the Northeast as a potential new market.

A future being decided right now, with the 5-strong Block Island Wind Farm sending a clear message: the U.S. can be powered without choking our air with smog.

“I do believe that starting small has made sense,” said Bryan Martin, Deepwater Wind’s chairman and D. E. Shaw’s head of United States private equity investment. “I would say that the next projects are going to be substantially bigger.”

Initial financing for the $300 million project came from the D. E. Shaw Group, a big investment firm based in Manhattan. The turbines are locked for now, but they will be turned on sometime in October and after a few weeks of testing and fine-tuning, America’s first offshore wind farm will begin pumping power into the New England electric grid.



A plastic model of the turbine driven by supercritical CO2. Credit: GE Global Research

A desk-sized turbine can power 10,000 homes

Fresh from the GE Global Research lab is this tiny monster: a turbine small enough you can hold in your hands, but powerful enough to provide energy to a whole town. It’s secret lies in a couple of design features, but also the power agent. Instead of steam, the “minirotor” as it’s been nicknamed is driven by supercritical carbon dioxide.

A plastic model of the turbine driven by supercritical CO2. Credit: GE Global Research

A plastic model of the turbine driven by supercritical CO2. Credit: GE Global Research

The carbon dioxide is heated to 700 °C under high pressure which causes it to enter a state called supercritical — neither gas, nor liquid. Once it passes through the turbine, the CO2 is cooled and then repressurized for another pass, MIT Technology Review reports.

Most turbines today used for energy generation are powered by steam. The GE design is better in almost all respects thanks to using the supercritical carbon dioxide. For one, it’s 50 percent efficient at turning heat into electricity, versus 40 percent in the case of steam. Secondly, less compression is required and heat transfer can be achieved. Finally, it only takes a couple of minutes to crank up the GE turbine, whereas steam needs at least 30 minutes to form.

In a coal power plant, for instance, this startup issue isn’t much of a problem since these are designed to function more or less around the clock. The short waiting time of the CO2 turbine, however, makes it excellent for generating power from stored electricity. Instead of using batteries, a solar park could store the energy in salts. These are melted, then stored in insulated containers. When the energy is needed, the molten salts can be pumped out to release their heat through a heat exchange system.

“The key thing will come down to economics,” says Doug Hofer, the GE engineer in charge of the project. While there’s work ahead, he says, “at this point we think our economic story is favorable compared to batteries.”

For now, their prototype is for a 10MW turbine, but it could be easily scaled to the 500MW range, the GE engineers say.


turbine energy

Doubling renewable energy by 2030: not only feasible — it’s expensive not to

The International Renewable Energy Agency claims doubling worldwide renewable energy capacity fifteen years from now would provide savings which far exceed the costs.  It would create more jobs, boost economic growth and save millions of lives annually through reduced air pollution. All the incentives seem to be here, especially money wise — it would be expensive not to scale renewable energy, the report concludes.

turbine energy

Image: Pixabay

The key findings of the report titled “ Roadmap for A Renewable Energy Future” are:

  • It would result in 24.4 million jobs in the renewable energy sector by 2030, compared to 9.2 million in 2014;

  • It would reduce air pollution enough to save up to 4 million lives per year in 2030;

  • It would boost the global GDP by up to USD 1.3 trillion;

  • It would limit average global temperature rise to 2 °C above pre-industrial levels (when coupled with energy efficiency);

  • It would avoid up to 12 gigatonnes of energy-related CO2 emissions in 2030 – five times higher than what countries have pledged to reduce through renewable energy in their nationally determined contributions (NDCs).

A number of factors are considered in estimating REmap Options, including resource availability; access to finance; human-resource needs and supply; manufacturing capacity; policy environment; the age of existing capital stock as well as the costs of technologies by 2030.  The substitution cost is the difference between the annualised costs of the REmap Option and a non-renewable energy technology used to produce the same amount of energy (e.g., electricity, heat), then divided by the total renewable energy use in final energy terms.


Image: IRENA

Some countries already have a 30% RE share already in their energy mix. Others, like the United States, lag far behind but makeup for in potential. So does the United Arab Emirates (UAE).

“This analysis demonstrates that the transition to renewable energy is about doing more than simply switching sources – it shows how renewable energy is a critical tool for sustainable development. We see the evidence in the world around us, where hundreds of jurisdictions worldwide are showing that development benefits are maximized by going 100% renewable.” Anna Leidreiter, Senior Programme Manager Climate Energy at World Future Council

“Renewable energy has a huge potential for mitigating climate change, which this report of shows, while at the same time offering great potential for development and green inclusive growth. Because of its decentralised character renewable energy can offer access to energy to all people in all regions, to people who are not in economic centres or in power, supporting equity, education, health, community services and productive use.” Eco Matser, climate and energy program manager at Hivos

Samsø – The World’s Greenest Guinea Pig


If you were to be optimistic, where do you think mankind would get most of its energy a century from now? Most would say from renewable sources. In fact, this project has been going on for a few years now. But just as any project needs, this one has an experiment which so far has given very good results. What is this experiment? It’s called Samsø.What is it? Well Samsø is a Danish island situated about 15 km off the Jutland Peninsula, in which Denmark is situated. In the Viking period it was used as a meeting place. What’s so special about it? Well, in 1997 the island won a competition for a 10 year project to see if it is practical to generate all the energy from Renewable Energy alone. Because it has no conventional sources of energy, it was a great place.

How did they manage to achieve this? The big step was made by a community of people who are common shareholders in several turbines. The islanders are very involved in this activity, and the way they produce energy could perhaps be a great example for others. Relying just on turbines, they managed to become carbon neutral. What’s even more impressive perhaps is the fact that with completion of an offshore wind farm comprising 10 turbines, Samsø sometimes has enough energy to sell back to the mainland.

The people also heat their houses with solar panels and burned grass, while their cars run on biofuel that they also produce. The ambitios objective which was set for 2008 was achieved actually 5 years earlier, which gives even more hope for the future, a future where hopefully more and more places get their energy from renewable sources.