Google’s energy subsidiary has signed a 20-year power purchase agreement with NextEra Energy.

Google will begin buying 114 megawatts of electricity from an Iowa wind farm later this year. Google intends to sell this energy on wholesale markets, and simultaneously buy energy where they need it.

By buying the wind energy directly, Google has created a giant hedge against both rising energy prices and the future cost of compliance with emissions reduction mandates

The company also pointed out that "our deal has a greater impact on the renewable industry than simply buying RECs from third parties; our long-term commitment directly frees up capital for the developer to build more wind projects … Through the long term purchase of renewable energy at a predetermined price, we’re partially protecting ourselves against future increases in power prices. This is a case where buying green makes business sense.".

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A group of 29 scientists have published an article in the prestigious Science journal arguing for the development of perennial grain crops which have been described as potentially "the biggest agricultural revolution for 10,000 years".

Currently, most grain grown around the world has to be replanted after every crop. 70% of all cropland is used for annual cereals, oilseeds and legumes. Thia consumes a lot of resources and is hard on the land.

The scientists argue that perennial grain, in addition to not needing replanting - saving farm machinery passing over and compacting the ground and reducing fuel consumption - would have a much deeper and more powerful root system than annuals. This would mean that it used water much more efficiently.

Other benefits of a deep perennial root system would be less erosion and better carbon sequestration. Perhaps most importantly, such a field might need as little as 3% of the fertiliser required by annuals. Not only are nitrate fertilizers energy-intensive to make, they are also prone to washing out of fields to pollute water supplies, kill habitats and cause other ecologcal damage.

Perennial fields would also require much less herbicide for control weeds.
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Engineers at Isentropic Ltd, a company in Cambridge UK, have developed a system fo storing large amounts of energy cheaply using gravel.

Currently, the most economically viable way of storing large amounts of energy is through pumped hydro, in which excess electricity is used to pump water up a hill. The water is held back by a dam until the energy is needed and then released to turn turbines and generate electricity.

Isentopic claims that its gravel-based battery would be able to store equivalent amounts of energy but use less space and be cheaper to set up.

The system consists of two silos filled with gravel. Electricity is used to heat and pressurise argon gas that is fed into one of the silos, heating the gravel to 500°C. When the gas leaves the chamber, it has cooled to ambient temperature but is still pressurised. The pressurised argon is fed into the second silo, where it expands back to normal atmospheric pressure. This process acts like a giant refrigerator, causing the temperature inside the second chamber to drop to -160°C.

In effect, electrical energy is stored as a temperature difference between the two rock-filled silos. To release the energy, the cycle is reversed, and as the energy passes from hot to cold it powers a generator that makes electricity.
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Shale-gas drilling involving hydraulic fracturing has been increasingly used in the United States and Canada.

A new documentary called Gasland focuses on the impact that the natural gas extraction process has on communities and the environment.

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The Solar PowerFlower is a portable concentrated photovoltaic power generator intended for agricultural use.

It was designed by Jason Halpern, co-founder of PowerFlower Solar, who began developing the technology while still a student at the University of Pennsylvania.

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The Plumas and Sierra Counties in California are testing a smart grid using the television broadcasting system’s "white space".

"White space" is the part of the broadcast spectrum left vacant when television broadcasting is switched from analogue to digital. It can transmit data significantly faster than the current standard Internet Wi-Fi, and can be broadcast for extended distances and through obstacles - making it ideal for use in smart grid communications.

The Plumas and Sierra Counties are located in the Sierra Nevada Mountains and present some very technical challenges with respect to wireless coverage - making them a good test site for the technology.

The smart grid trial is being conducted by Spectrum Bridge, which has a database which dynamically assigns white space frequences to prevent interfernce with TV broadcasts, Google which is providing power metering and control software and the local electricity and telecommunications utility.

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Researchers at the Massachusetts Institute of Technology, led by Associate Professor Yang Shao-Horn, in collaboration with Professor Paula Hammond, have found that using carbon nanotubes for one of the battery’s electrodes produced up to a tenfold increase in the amount of power that a lithiun-ion battery could deliver from a given weight of material.

In the new battery electrode, carbon nanotubes are "electrostatically self-assembled" into a tightly bound structure that is porous at the nanometer scale. The carbon nanotubes have many oxygen groups on their surfaces, which can store a large number of lithium ions. This enables carbon nanotubes to serve as the positive electrode in lithium batteries.

Carbon nanotubes are a form of pure carbon in which sheets of carbon atoms are rolled up into tiny tubes. Normally, carbon nanotubes on a surface tend to clump together in bundles, leaving few exposed surfaces to undergo reactions. The "electrostatic self-assembly" process incorporates organic molecules on the nanotubes and they assemble in a way that has a many exposed surfaces.

The new batteries have some of the advantages of both capacitors and conventional lithium batteries. Like capacitors, they can produce very high power outputs in short bursts - but the energy output for a given weight of the new electrode material is five times greater than for conventional capacitors. Like conventional batteries, they can provide lower power steadily for long periods - but the total power delivery rate with the new batteries is10  times that of lithium-ion batteries

In addition to their high power output, the carbon nanotube electrodes showed very good stability over time. After 1,000 cycles of charging and discharging a test battery, there was no detectable change in the material’s performance.

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Spain has overtaken the US as the biggest solar electricity generator in the world.

The opening of the new La Florida solar plant at Alvarado, Badajoz, in the west of the country, takes Spain’s solar output to 432 megawatts, compared with the US output of 422 megawatts.

The La Florida plant produces 50 megawatts of power with a parabolic trough system covering 550,000 square metres.

Protermosolar, the association that represents Spain’s solar energy sector, says that within a year another 600 megawatts will have come on-stream and that by 2013 solar capacity will have reached 2,500 megawatts..

Spain is also one of the world’s leading producers of wind power, with windfarms producing around 20,000 megawatts of electricity, and the third largest producer of hydro-electricity, after China and the US.

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The media is fond of quoting claims that the internet will soon be using more power than the airline industry, that it will consume half of all the electricity produced or that two Google searches release as much CO₂ as boiling a kettle of water.

The Google search myth arose from a Times article in January 2009 which said that "a typical search generates about 7g of CO₂. Boiling a kettle generates about 15g". Urs Hölzle, Google’s Senior Vice President Operations, posted a response saying the typical search actually releases only 0.2 grams of CO₂ - that’s 75 searches per kettle. The Times has since published a "clarification" but the original figure still gets quoted.

On the broader issue, the amazing estimates of the amount of electricity that the internet supposedly uses stem from a 1999 article in Forbes magazine revealingly titled "Dig More Coal - the PCs Are Coming". The article claimed that the internet was then accounting for 8% of all electricity use with the total used by all computers (including the internet) amounting to 13%. Highly detailed studies by the Lawrence Livermore Laboratory show that he actual figures at that time were less than 1% for the internet and about 3% for all computers.
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Researchers at Purdue University have developed a new highly efficient technique for making hydrogen fuel cells suitable for vehicles. The technology has the potential to be twice as effective as current fuel cells at around half the temperature and much lower pressure.

The process uses ammonia borane, a high hydrogen-content powdered chemical and combines two hydrogen generating processes — hydrolysis and thermolysis — to achieve conditions appropriate for use in vehicles.

Currently hydrogen fuel cells run at pressures of aound 5,000 psi. Hydrolysis alone requires a catalyst to turn hydrogen into energy, and thermolysis requires a temperature of 170°C to function. By combining hydrolysis and thermolysis processes, and introducing ammonia borane into the reaction, the required temperature is lowered to about 85°C and the pressure requirements lower to 200 psi.

The researchers believe that, if this technology can be scaled up, it would be the perfect reaction to generate electricity for hydrogen fuel cell vehicles and small appliances. As well as scaling up the process, the researchers are working on ways to recycle the ammonia borane used in the reaction and return it to its original state.

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