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.".

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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