Tag Archives: fossil fuels

NREL energy

US electricity demand could be 80% supplied by renewable sources by 2050

NREL energyAccording to a recently publicized rapport by the  Department of Energy’s National Renewable Energy Laboratory (NREL), renewable energy sources could account for as much as 80% of the US’s electricity demand by 2050. The rapport signals the various difficulties that need to be overcome to reach this goal, and note that while 80% might be very challenging to reach, a 50% reach is highly possible.

The major players in the renewable energy game of 2050 will be  wind, photovoltaics, and biomass power plants. Surprisingly, hydropower, which is the current dominant renewable energy source in the US, will amount to a smaller proportion in the future.  Increased offshore wind and biomass power plants is where the Department of Energy is currently seeking to invest, and hopefully reach its ambitious 80% renewable energy covered demand.

The US has made significant efforts in increasing the renewable energy stake, and in 2010 renewable energy actually surpassed nuclear energy in provided electricity. Still, the nation is still lagging pretty far behind, compared to other countries’ efforts. Currently, Germany has 17 GW of solar PV installed, versus less than 4 GW in the US – even though the US covers a much larger surface. Scotland has over 31% of its current electricity demand covered by renewable energy, and, along with Denmark, plans to reach 100% by 2050.

The study notes that 439 gigawatts of wind capacity will be required in 2050 for the U.S. to be adequately supplied by renewables. Only 50 gigawatts are currently installed, meaning if the US is keen on reaching its goal, it needs to develop 10 gigawatts per year for almost 40 years, or install ~3,000 wind turbines per year.

“Annual renewable capacity additions that enable high renewable generation are consistent with current global production capacities but are significantly higher than recent U.S. annual capacity additions for the technologies considered,” said the study. “No insurmountable long-term constraints to renewable electricity technology manufacturing capacity, materials supply, or labor availability were identified.”

Whether the Department of Energy can back its claims and walk the talk, it remains to be seen. What’s pretty certain is that fossil fuel monopoly is shacking more nervously by the day.

source: IEEE

Answering our readers: The Earth’s core

I’ve been receiving questions from you people for years now – and really, this made me happy, because it says that people want to learn and understand more. But I’ve been answering them individually, and now, I’m thinking it would be better to post the answers on the website, so more people can read them. So, starting today, we have a new category, in which we’ll be doing just this; also, I’d like to take advantage of this to encourage you to send any scientific questions you might have, regardless of how silly you might feel they are – we’ll do our best to answer them. I’ll post a shorter version of the question.

Question: Why is the core so hot, and is it connected in any way to fossil fuels?

No, it’s not connected in any way to fossil fuels; fossil fuels are located in the crust at (generally speaking) several kilometers blow surface, and the core is at 5150 kilometers beneath surface. Let’s detail.

For starters, we’ll be discussing about Earth’s core. The Earth’s core is made of two parts: a solid inner core and a liquid outer core. The outer core has a temperature of 4400 °C – 6100 °C, while the inner core has an average of 5505 °C – which is about as big as the temperature on the surface of the Sun – and there are a number of reasons why this temperature is so high.

Generally speaking, the temperature rises as you’re going towards the inner core, growing with pressure. Earth has a significant amount of heat left over from when it fist condensed as a planet; sure, we’re walking around here find and dandy, but the depths of the Earth haven’t had enough time to cool down. This amounts for about 5-10 percent of the heat. Gravitational heat matters about just as much. What is gravitational heat? Well imagine our planet, in its initial stages, as a huge mass of lava (or honey, if that works better for you). If you put, say, a rock in a jar of honey, it will go down. The same thing happened with the Earth: the denser elements went down towards the core, and this movement continues today, causing friction which generates heat.

Then you have latent heat, which arises as the Earth cools from inside out; liquid metal solidifies, releasing heat in the process. But by far, the most important source of heat our planet has comes from radioactivity (mostly in the mantle). Radioactive decay causes up to 90 percent of all the heat inside our planet! There’s a good chance sometime in the future our planet will cool enough to fully solidify, and will become ‘dead’, much like the Moon. However, before this happens, the Sun will grow into a red supernova so large that it will also engulf Earth – so any heat in the mantle will hardly matter.

[VIDEO] A brief history of fossil fuels

As fossil fuel resources significantly diminish every year, the world gets ever tumultuous and panic slowly begins to settle moment by moment. Luckily, suitable energy is a topic which gets a lot of attention nowadays, although not nearly as publicized as it should, seeing how the general public is still at a low awareness level.

The Post Carbon Institute is doing its best to pitch in by releasing this very informative and entertaining animated video which offers a brief history of fossil use by mankind and how the post carbon society might look like in the future if the necessary steps towards sustainable life are taken.

Click on the YouTube player below and enjoy!