Hydropower, Storage

Cape Wind Records Strong Winds During Peak Electricity Hours

Cape Wind’s Scientific Data Tower has recorded strong winds on Horseshoe Shoal in Nantucket Sound during each of the past ten record electric demand days in New England. These results are available in a new report published by Cape Wind entitled “Comparison of Cape Wind Scientific Data Tower Wind Speed Data with ISO New England List of Top Ten Electric Demand Days”.

The report finds that Cape Wind would have produced an average of 321 megawatts (MW) when electric demand was at its peak during each of the past ten record-setting electric demand days as recorded by the Independent System Operator of New England (ISO-NE), the region’s electric grid manager.

Nine of these record demand days have occurred on very hot afternoons of the summers of 2006 and 2005 and one occurred last week on June 27, 2007. Cape Wind’s production during these times of record electric demand represents 76% of Cape Wind’s maximum potential of 420 MW and is 76% greater than Cape Wind’s average expected output of 182 MW.

Cape Wind’s Vice President of Engineering Len Fagan explained why Cape Wind’s production would be higher during these hot summer afternoons that set electricity demand records, “These tend to be the hottest summer days when the air over the land heats up faster than the air over the ocean, this creates a difference in air density and denser air over the ocean expands toward the land, this is called the sea breeze effect and you get it most during the afternoon when electric demand is highest.”

Days that experience record electric demand tend also to be days when air quality alerts are issued by environmental agencies and when wholesale spot market electricity prices are at their height because older, less-efficient, highly polluting and expensive backup power generators are operating. Taking advantage of the sea breeze cleanly provides electricity that would otherwise need to be provided by these high polluting and expensive sources during times of high demand.

Previously, the U.S. Department of Energy reported that Cape Wind would have been at full production during almost the entire 3-day sub-zero cold snap in January, 2004 when electric grid managers were considering the need for a rolling blackout due to a shortage of natural gas available for electrical generation because of elevated demand for gas heat.

“These reports taken together demonstrate that Cape Wind would be providing substantial power when New England needs it the most, during the hottest and coldest days,” Cape Wind President Jim Gordon said.