Chicago is known as the Windy City, but in truth, Boston is breezier. Beantown has the highest average wind speed of any major city in the United States, at 12.4 mph.
Does it make you wonder how much energy might be generated if wind turbines were placed atop some of its tall buildings? It makes the folks at Eastern Wind Power wonder. A maker of vertical-axis wind turbines, EWP has embarked on a project to gather wind data from 10 high-rises in Boston. It hopes to show that its turbines could be significant power producers for big-city buildings.
EWP so far has Web-based weather stations from Onset Computer Corporation on two buildings — the Equity Office Properties building at 60 State Street and the Massachusetts Eye and Ear Infirmary — to measure wind speed, wind gust and wind direction. The plan is to collect data from eight more high-rises in downtown Boston by 2013.
Exactly how much wind is available is a hugely important factor in wind power. That’s because the power in the wind is proportional to the cube of its speed. So the amount of power produced rises exponentially as the wind speed increases. According to the Department of Energy, if your site has an annual average wind speed of about 5.6 meters per second – or about 12.6 mph, very close to Boston’s average — it has twice the energy available as a site with a 10 mph average.
This takes on added importance with small systems because, to be honest, they are lilliputian compared to wind’s big boys. The mammoth horizontal turbines spinning away in Texas and California and elsewhere can pump out 2 megawatts or more of power. EWP has a 50-kilowatt (kW) vertical-axis turbine.
But we are talking about windy Boston here – and wind speed climbs substantially with elevation. The 60 State Street high-rise isn’t the tallest in Boston, but soaring 509-feet heavenward it pokes well into the strong winds aloft (Mass Eye and Ear appears to be quite a bit shorter, so it will be interesting to see what the wind study turns up there.)