I'm reading up on the economics of power outages at the moment, and I stumbled across the graph above in this National Wildlife Federation analysis. It shows the number of power outages caused by non-weather related factors, and weather related factors (from 1992-2010 in the US). There has been a material increase in both categories, but much more so in the weather related problems. The NWF say:
Power outages and disturbances are estimated to cost the U.S. economy between $25 and $180 billion annually and severe weather is a factor in more than half of the outages in recent years. Indeed, major power outages caused by weather have increased from about 5 to 20 each year in the mid 1990s to about 50 to 100 each year during the last five years, with significant year-to-year variability. These major weather-related outages are almost always caused by an interruption in electricity distribution, rather than in electricity generation. Changes in extreme weather, power transmission infrastructure and maintenance practices, and demographic trends may all be contributing to more frequent power outages.The data here are confusing to me, so I'm hesitant to draw a final conclusion. In particular, I'd want to really understand the large increase in non-weather-related outages. But certainly the idea that the extreme weather of recent years is degrading electricity reliability seems worth exploring.
Strong winds are a major contributor in around 80 percent of major weather related power outages. Since the early 1990s, insured damages from wind storms have increased by a factor of 4 to 5, today costing the United States an average of $174 million a year. There has not been a trend in the annual number of catastrophic wind events over this time period, suggesting that either the wind events are becoming more severe or more property has been developed in places vulnerable to wind damage.
Some of the biggest outages are caused by hurricanes and other tropical storms, which are expected to have stronger winds and more rainfall because of climate change. Millions of customers can lose power during major storms. For example, Hurricane Ike, which made landfall near Galveston, Texas, in September 2008, left 3.9 million customers in nine states without power, many for a week or longer.