Renewables & efficiency - Apr 29
Giant gravel batteries could make renewable energy more reliable
Alok Jha, The guardian
Newly designed giant gravel batteries could be the solution to the on-off nature of wind turbines and solar panels. By storing energy when the wind stops blowing or the sun stops shining, it is hoped the new technology will boost to renewable energy and blunt a persistent criticism of the technology - that the power from it is intermittent.
Electricity cannot be stored easily, but a new technique may hold the answer, so that energy from renewables doesn't switch off when nature stops playing ball. A team of engineers from Cambridge think they have a potential solution: a giant battery that can store energy using gravel.
"If you bolt this to a wind farm, you could store the intermittent and relatively erratic energy and give it back in a reliable and controlled manner," says Jonathan Howes, founder of Isentropic and previously an engineer at the Civil Aviation Authority.
The Labour government committed to cutting the country's carbon emissions by 34% by 2020 and 80% by 2050, both relative to 1990 levels. To achieve this, ministers outlined plans to build thousands of wind turbines by 2020. The only economically viable way of storing large amounts of energy is through pumped hydro – where excess electricity is used to pump water up a hill. The water is held back by a dam until the energy is needed, when it is released down the hill, turning turbines and generating electricity on the way.
Isentopic claims its gravel-based battery would be able to store equivalent amounts of energy but use less space and be cheaper to set up. Its system consists of two silos filled with a pulverised rock such as gravel. Electricity would be used to heat and pressurise argon gas that is then fed into one of the silos. By the time the gas leaves the chamber, it has cooled to ambient temperature but the gravel itself is heated to 500C...
(26 April 2010)
Regulators Approve First Offshore Wind Farm in U.S.
Katherine Q. Seelye, The New York Times
After nine years of regulatory review, the federal government gave the green light Wednesday to the nation’s first offshore wind farm, a highly contested project off the coast of Cape Cod.
The approval of the 130-turbine farm gives a significant boost to the nascent offshore wind industry in the United States, which has lagged far behind Europe and China in harnessing the strong and steady power of ocean breezes to provide electricity to homes and businesses.
With Gov. Deval Patrick standing beside him, Interior Secretary Ken Salazar announced at a news conference at the Massachusetts Statehouse that the government had approved a permit for Cape Wind Associates, a private venture, to build the farm.
“I am approving the Cape Wind project,” Mr. Salazar said. “This will be the first of many projects up and down the Atlantic coast.”
The Cape Wind turbines would lie in Nantucket Sound, about five miles from the nearest shoreline, and cover 24 square miles, roughly the size of Manhattan. The tip of the highest blade of each turbine would reach 440 feet above the water.
But the project is hardly shovel ready. Several regulatory hurdles remain, and opponents of the wind farm have vowed to go to court, potentially stalling Cape Wind for several more years...
(28 April 2010)
Colorado Shows How It's Done
Craig Severance, energy economy online
As the U.S. Senate now prepares to consider a new climate bill, Congress can consider how readiily climate action can take hold, through the example of Colorado. This politically diverse state has aggressively embraced climate action as a way to grow its economy.
Bipartisan Support. Colorado's action plan is noteworthy because key elements of the plan have received strong bi-partisan support, in a "purple" Swing State that is neither dependably Democratic nor Republican. As an example, the latest measure adopted -- a bill to encourage conversion of older coal-fired power plants to cleaner natural gas -- was co-sponsored by the Republican Senate Minority Leader Sen. Josh Penry and several other Republicans, along with most Democrats and Democratic Governor Bill Ritter.
This strong support for climate action is remarkable, considering Colorado is one of the nation's most heavily coal-dependent states.
Coal Was King. As recently as 2005, Colorado relied upon coal to supply over two thirds of its electricity, making Colorado far more dependent on pollution-spewing coal than the nation as a whole, which averages around half of total electricity from coal. Coal has been cheap yet produces massive carbon dioxide emissions which cause global warming. The idea of a major coal-dependent state such as Colorado becoming a climate change leader was thus a daunting challenge.
Colorado is nevertheless now leading the way to achieve one of the highest reductions in carbon emissions anywhere in the world. Colorado is on track to achieve a total 30% reduction by 2020 in CO2 emissions from its electric power industry. This is far ahead of 17% reduction by 2020 greenhouse gas reduction goals set in Congressional climate legislation -- showing that even a "coal state" can far exceed those goals.
As the nation's 8th largest coal-producing state, Colorado could have chosen to resist climate change action like many other states with strong coal lobbies. However, led by Colorado's own citizens through a 2004 renewable power initiative, strong leadership by Governor Bill Ritter and bipartisan action by the Colorado legislature, Colorado is instead showing "how it's done" to the rest of the country and the world...
(24 April 2010)
Windmill Boom Curbs Electric Power Prices for RWE
Jeremy van Loon, Bloomberg
On windy nights in northern Germany, consumers are paid to keep the lights on.
Twice this year, the nation’s 21,000 wind turbines pumped out so much power that utilities reduced customer bills for using the surplus electricity. Since the first rebate came with little fanfare at 5 a.m. one October day in 2008, payments have risen as high as 500.02 euros ($665) a megawatt-hour, about as much as a small factory or 1,000 homes use in 60 minutes.
The wind-energy boom in Europe and parts of Texas has begun to reduce bills for consumers. Electricity-network managers have even ordered windmills offline at times to trim supplies. That hurts profit for wind-farm operators, said Christian Kjaer, head of the European Wind Energy Association, which represents RWE AG of Germany, Spain’s Iberdrola SA and Dong Energy A/S of Denmark.
“We’re seeing that wind energy lowers prices, which is great for the consumers,” Kjaer said at his group’s conference in Warsaw this week. “We as producers have to acknowledge that this means operating the existing plant fewer hours a year, and this has an effect on investors” and profit.
After years of getting government incentives to install windmills, operators in Europe may have become their own worst enemy, reducing the total price paid for electricity in Germany, Europe’s biggest power market, by as much as 5 billion euros some years, according to a study this week by Poeyry, a Helsinki-based industry consultant.
(23 April 2010)
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