Apple has dropped a few more details about its huge new data centre in Maiden, North Carolina in an update to its environmental policy published yesterday.
A big feature of the new billion-dollar data centre – needed to keep Siri chatting back, and to let new OS Mountain Lion sync games in real time between iPhones and Macs – is a 100-acre solar panel field, which, along with a biofuel burner, Apple says will provide a "high percentage" of the data centre's energy needs.
But the energy from the solar field and from a bio-gas powered fuel cell could be as little as 9 per cent of the total that the data centre slurps - that is if Greenpeace's estimate of the energy needed is accurate. The whale-huggers predict that the massive data centre will require 100 megawatts to run at full capacity.
More conservative estimates would put the Maiden centre's power draw a little lower. A $210m Facebook data centre in Prineville, Oregon draws a reputed 28 megawatts off the local grid. But though Apple's Maiden data centre is 500,000ft2 and has a $1bn price tag, quadrupling the cost won't necessarily quadruple the power draw.
The Maiden centre is one of the biggest data centres ever built but is more likely to be in the range of existing big data centres than completely in a league of its own: the US government runs several of the world's biggest data centres and these typically draw about 60 megawatts of power. We'd estimate that the power consumption of Maiden will be around the 50 to 60 megawatt mark.
We've obviously asked Apple to tell us how much energy the centre will use in a year, but in the absence of their response, estimates are all we have to go on.
Apple states that the solar panel field will produce 42 million kWh of energy annually and that the biogas fuel cell plant will produce 40 million kWh annually. Together they will produce 82 million kWh a year or simply 9,360 kWh on average an hour - a rate of 9,360 kilowatts or 9.36 megawatts between the two of them, averaged out over the year.
If the whale-huggers are right and the data centre will draw up power at a rate of 100 megawatts, that means that renewables will provide only 9.36 per cent of the power needed and that over 90 per cent of the centre's power needs will have to be drawn from North Carolina's power grid.
If our more conservative guess is right and the centre is sucking up energy at a rate of 60 megawatts, that would mean that Apple's renewables installations would supply 15 per cent of the centre's power, with the rest coming from the grid. North Carolina is a popular location for data centres because grid electricity there is cheap: both Google and Facebook have sited big centres there.
Whether 9-15 per cent qualifies as a "high percentage" of renewable power is a matter of perspective.
The update of Apple's environmental policy also includes some other tidbits about Apple's right-on energy policy: for example applying reflective paint to the roofs and windows of their buildings, making disposable tableware in the cafeteria compostable and a shared bike programme for Cupertino employees. Oh yes, and they say their employees save energy - and presumably money - by using Apple computers.
Apple also says that its facilities - its offices, retail stores and data centres - only account for 2 per cent of its greenhouse gas emissions; the bulk - 60 per cent - comes from manufacturing its devices.
2012年2月19日星期日
Solar enthusiasm exceeds practicality
Germany once prided itself on being the "photovoltaic world champion", doling out generous subsidies totalling more than $US130 billion to citizens to invest in solar energy, according to Germany's Ruhr University.
But now the German government is vowing to cut the subsidies sooner than planned and to phase out support over the next five years. What went wrong?
There is a fundamental problem with subsidising inefficient green technology: it is affordable only if it is done in tiny, tokenistic amounts. Using their government's generous subsidies, Germans installed 7.5 gigawatts of photovoltaic capacity last year, more than double what the government deemed "acceptable". It is estimated this will lead to a $US260 ($243) hike in the average consumer's annual power bill.
According to Der Spiegel, even members of Chancellor Angela Merkel's staff are now describing the policy as a massive money pit. Philipp Rosler, Germany's Minister of Economics and Technology, has called the spiralling solar subsidies a "threat to the economy".
Germany's enthusiasm for solar power is understandable. We could satisfy all of the world's energy needs for an entire year if we could capture just one hour of the sun's energy. Even with the inefficiency of current PV technology, we could meet the entire globe's energy demand with solar panels by covering 250,000sq km, about 2.6 per cent of the Sahara Desert.
Unfortunately, Germany, like most of the world, is not as sunny as the Sahara. And while sunlight is free, panels and installation are not. Solar power is at least four times more costly than energy produced by fossil fuels. It also has the distinct disadvantage of not working at night, when much electricity is consumed.
In the words of the German Association of Physicists, "solar energy cannot replace any additional power plants". On short, overcast winter days, Germany's 1.1 million solar-power systems generate no electricity. The country is then forced to import considerable amounts of electricity from nuclear power plants in France and the Czech Republic. When the sun failed to shine last winter, one emergency back-up plan powered up an Austrian oil-fired plant to fill the supply gap.
Indeed, despite the massive investment, solar power accounts for only about 0.3 per cent of Germany's total energy. This is one of the key reasons why Germans now pay the second-highest price for electricity in the developed world . Germans pay three times more than their American counterparts.
Moreover, this sizeable investment does remarkably little to counter global warming. Even with unrealistically generous assumptions, the unimpressive net effect is that solar power reduces Germany's CO2 emissions by roughly eight million tonnes, or about 1 per cent, for the next 20 years.
When the effects are calculated in a standard climate model, the result is a reduction in average temperature of one twenty-thousandth of a degree celsius. By the end of the century, Germany's $US130bn solar panel subsidies will have postponed temperature increases by 23 hours.
Using solar, Germany is paying about $US1000 per tonne of CO2 reduced. The current CO2 price in Europe is $US8. Germany could have cut 131 times as much CO2 for the same price. Instead, the Germans are wasting more than 99c of every euro that they plough into solar panels.
It gets worse: because Germany is part of the EU emissions trading system, the actual effect of extra solar panels in Germany leads to no CO2 reductions, because total emissions are already capped.
Instead, the Germans simply allow other parts of the EU to emit more CO2. Germany's solar panels have only made it cheaper for Portugal or Greece to use coal. Defenders of Germany's solar subsidies also claim that they have helped to create "green jobs" but each job created by green-energy policies costs an average of $US175,000, considerably more than job creation elsewhere in the economy. And many "green jobs" are being exported to China, meaning that Europeans subsidise Chinese jobs, with no CO2 reductions.
Germany's experiment with subsidising inefficient solar technology has failed. What governments should do instead is to focus first on increasing research and development to make green-energy technology cheaper and more competitive. Production should be ramped up later.
But now the German government is vowing to cut the subsidies sooner than planned and to phase out support over the next five years. What went wrong?
There is a fundamental problem with subsidising inefficient green technology: it is affordable only if it is done in tiny, tokenistic amounts. Using their government's generous subsidies, Germans installed 7.5 gigawatts of photovoltaic capacity last year, more than double what the government deemed "acceptable". It is estimated this will lead to a $US260 ($243) hike in the average consumer's annual power bill.
According to Der Spiegel, even members of Chancellor Angela Merkel's staff are now describing the policy as a massive money pit. Philipp Rosler, Germany's Minister of Economics and Technology, has called the spiralling solar subsidies a "threat to the economy".
Germany's enthusiasm for solar power is understandable. We could satisfy all of the world's energy needs for an entire year if we could capture just one hour of the sun's energy. Even with the inefficiency of current PV technology, we could meet the entire globe's energy demand with solar panels by covering 250,000sq km, about 2.6 per cent of the Sahara Desert.
Unfortunately, Germany, like most of the world, is not as sunny as the Sahara. And while sunlight is free, panels and installation are not. Solar power is at least four times more costly than energy produced by fossil fuels. It also has the distinct disadvantage of not working at night, when much electricity is consumed.
In the words of the German Association of Physicists, "solar energy cannot replace any additional power plants". On short, overcast winter days, Germany's 1.1 million solar-power systems generate no electricity. The country is then forced to import considerable amounts of electricity from nuclear power plants in France and the Czech Republic. When the sun failed to shine last winter, one emergency back-up plan powered up an Austrian oil-fired plant to fill the supply gap.
Indeed, despite the massive investment, solar power accounts for only about 0.3 per cent of Germany's total energy. This is one of the key reasons why Germans now pay the second-highest price for electricity in the developed world . Germans pay three times more than their American counterparts.
Moreover, this sizeable investment does remarkably little to counter global warming. Even with unrealistically generous assumptions, the unimpressive net effect is that solar power reduces Germany's CO2 emissions by roughly eight million tonnes, or about 1 per cent, for the next 20 years.
When the effects are calculated in a standard climate model, the result is a reduction in average temperature of one twenty-thousandth of a degree celsius. By the end of the century, Germany's $US130bn solar panel subsidies will have postponed temperature increases by 23 hours.
Using solar, Germany is paying about $US1000 per tonne of CO2 reduced. The current CO2 price in Europe is $US8. Germany could have cut 131 times as much CO2 for the same price. Instead, the Germans are wasting more than 99c of every euro that they plough into solar panels.
It gets worse: because Germany is part of the EU emissions trading system, the actual effect of extra solar panels in Germany leads to no CO2 reductions, because total emissions are already capped.
Instead, the Germans simply allow other parts of the EU to emit more CO2. Germany's solar panels have only made it cheaper for Portugal or Greece to use coal. Defenders of Germany's solar subsidies also claim that they have helped to create "green jobs" but each job created by green-energy policies costs an average of $US175,000, considerably more than job creation elsewhere in the economy. And many "green jobs" are being exported to China, meaning that Europeans subsidise Chinese jobs, with no CO2 reductions.
Germany's experiment with subsidising inefficient solar technology has failed. What governments should do instead is to focus first on increasing research and development to make green-energy technology cheaper and more competitive. Production should be ramped up later.
2011年4月28日星期四
Nanosolar Snares a Gigawatt in Orders for its Thin-Film Solar Panels
Is thin really back in?
Thin-film solar, that is. Nanosolar announced Thursday that it had signed contracts to supply up to one gigawatt of its thin-film photovoltaic panels to European solar power plant builders over the next three to six years.
Nanosolar is one of several Silicon Valley startups that have attracted billions of dollars in venture capital to develop a thin-film technology called copper indium gallium selenide, or CIGS. Such solar cells use little expensive silicon, the main ingredient of conventional photovoltaic cells.
Thin-film cells can be printed on glass or flexible materials and though they’re less efficient at converting sunlight into electricity, the big pitch was that they can be manufactured at a lower cost. But then came a 50 percent fall in the price of conventional crystalline silicon photovoltaic modules as Chinese manufacturers rapidly ramped up production and many CIGS companies backed off their earlier optimistic projections.
And so those impressive 10-figure orders from customers need to be taken with a grain of salt as they don’t always materialize. For instance, in September 2009, Nanosolar announced a whopping $4.1 billion in orders and a manufacturing capacity of 640 megawatts at its German plant.
A year later when I met with a Nanosolar executive at the Solar Power International confab in Los Angeles, he acknowledged that not all those orders would be fulfilled, given the state of the economy and falling solar cell prices. The company had also ratcheted back its estimated manufacturing capacity. (On Thursday, Nanosolar said it would have an annual capacity of 115 megawatts by this fall.)
The latest orders are with two German companies, Belectric and Plain Energy, and with EDF Energies Nouvelles, a unit of the French energy giant. The developers will deploy the Nanosolar Utility Panel in photovoltaic power plants.
“Through this partnership with Nanosolar, we look forward to achieving a very competitive levelized cost of energy for our solar installations,” David Corchia, EDF Energies Nouvelles, said in a statement.
Thin-film solar, that is. Nanosolar announced Thursday that it had signed contracts to supply up to one gigawatt of its thin-film photovoltaic panels to European solar power plant builders over the next three to six years.
Nanosolar is one of several Silicon Valley startups that have attracted billions of dollars in venture capital to develop a thin-film technology called copper indium gallium selenide, or CIGS. Such solar cells use little expensive silicon, the main ingredient of conventional photovoltaic cells.
Thin-film cells can be printed on glass or flexible materials and though they’re less efficient at converting sunlight into electricity, the big pitch was that they can be manufactured at a lower cost. But then came a 50 percent fall in the price of conventional crystalline silicon photovoltaic modules as Chinese manufacturers rapidly ramped up production and many CIGS companies backed off their earlier optimistic projections.
And so those impressive 10-figure orders from customers need to be taken with a grain of salt as they don’t always materialize. For instance, in September 2009, Nanosolar announced a whopping $4.1 billion in orders and a manufacturing capacity of 640 megawatts at its German plant.
A year later when I met with a Nanosolar executive at the Solar Power International confab in Los Angeles, he acknowledged that not all those orders would be fulfilled, given the state of the economy and falling solar cell prices. The company had also ratcheted back its estimated manufacturing capacity. (On Thursday, Nanosolar said it would have an annual capacity of 115 megawatts by this fall.)
The latest orders are with two German companies, Belectric and Plain Energy, and with EDF Energies Nouvelles, a unit of the French energy giant. The developers will deploy the Nanosolar Utility Panel in photovoltaic power plants.
“Through this partnership with Nanosolar, we look forward to achieving a very competitive levelized cost of energy for our solar installations,” David Corchia, EDF Energies Nouvelles, said in a statement.
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