Question: What do you call it when an electricity plant takes up 38 square miles to create enough power for 500,000 homes?
Answer: The world's largest offshore wind farm, otherwise known as the London Array.
The collection of 175 giant Siemens turbines soaring out of the Thames Estuary - where the River Thames meets the North Sea east of London - has been feeding the U.K.'s grid since last April. Yesterday, Prime Minister David Cameron officially inaugurated it.
"This is a great day for Britain and a big win for renewable energy," Cameron proclaimed at the opening ceremony, as reported by BusinessGreen in The Guardian.
The 630-megawatt expanse promises to shrink the country's carbon footprint. The backers, who include energy companies Dong, E.ON and Masdar (from Denmark, Germany and the UAE respectively) said it will cut CO2 emissions by 900,000 tonnes a year.
Wind is without a doubt a CO2 enemy, more so even than photovoltaic energy when analyzed over the lifecycle of production, operation and retirement, according to one Nobel physicist. One of its downsides is that it does not blow reliably around the clock, although in areas like offshore Britain, that is is less of an issue than elsewhere. Wind is a resource, and the U.K. should be applauded for tapping it. The London Array takes over the top global spot from another British offshore installation, the 500-megawatt Great Gabbard farm up the coast.
But when I see numbers like 38 square miles to produce 630 megawatts, I start to wonder about efficiency. A nuclear power plant could churn out the same amount on a sliver of the territory without the far flung maintenance challenges of offshore. So could, gulp, coal or gas.
An offshore wind farm can make sense if you have the territory and the money and the constantly blowing wind. But the environmental movement should also embrace nuclear - especially the alternative forms of nuclear power increasingly under development around the world - for clean, CO2-free and compact energy sources.
Photo from London Array
Is the next stage of the London Array for the birds?
Winds of change are blowing environmentalists towards nuclear: