As the inhabitants of East Coast America get to grips with the mess left by Hurricane Sandy, debate has inevitably been raging over whether the storm was the latest sign of a rapidly changing climate. Both candidates in the US presidential race have been noticeably reticent in making any public comments on Sandy’s significance in the wider climate change narrative, though some prominent politicians have been more vocal, notably New York state Governor Andrew Cuomo, who said that “anyone who says there’s not a dramatic change in weather patterns, I think is denying reality”.
For those who agree with him and believe that this trend of changing weather patterns is a result of human activity, Hurricane Sandy would seem to be the perfect justification for a ramping up of clean technologies such as solar that, if it’s not already too late, could help avert further disasters.
As it happens, it looks as though the fabric of East Coast America’s rooftop solar installations held out remarkably well under the Sandy onslaught. According to press reports in the wake of the hurricane, rooftop solar units in neighbourhoods that had been otherwise laid to waste by the storm were left relatively unscathed.
This is perhaps not altogether surprising, given that PV units are designed to withstand freak weather conditions. Several US installers issued guidance to customers ahead of the storm reassuring them that no special measures were needed to secure rooftop units, as they were “designed, installed and inspected to the most challenging local weather conditions”, in the words of one installer, Sunrun.
Where they were less useful, however, was in continuing to provide their owners with electricity throughout a power blackout that affected some 7.5 million people across 15 states. As Sunrun and others reminded their customers, grid-tied domestic PV systems are designed to shut down during a utility power outage, even though they remain energised.
What this meant was that although still technically functioning, none of the PV systems in areas of the US hit by power blackouts were actually generating electricity. So solar owners who were smugly anticipating being able to carry on watching real-time TV coverage of the storm while their neighbours sat in darkness would in fact have found themselves in exactly the same boat. As installer Realgoods Solar instructed its customers: “Please have extra candles, flashlights and batteries on hand.” In other words, your expensive solar units will be useless if the grid goes down.
This highlights a wider problem that the US and other countries will have to contend with as they look to install increasing volumes of renewable generation capacity: that centralised grid systems are clumsy and ill-suited to these next-generation technologies. They’re vulnerable to extreme weather events such as Sandy (which judging by recent trends are only going become more frequent), difficult to fix if they go wrong and do not make the best use of the inherent resilience of decentralised generation systems.
What Sandy laid bare is that without significant investment in smart grids and distributed power networks backed up by energy storage systems, renewable energy technologies will never be able to live up to their potential in keeping the lights on.