Wednesday, January 14, 2009

The Silent Windmills of Altamont

We had Christmas with Alice’s daughters’ families in Walnut Creek, about forty miles east of San Francisco, overnighted with a friend in Livermore not far from the five-acre ranch where we lived for nine years, and on the last day of 2008 we set off for Southern California via Highway 580. Soon we were passing through the Altamont Pass, famed as the site of a massive free rock concert in 1969 featuring the Rolling Stones with the Hell’s Angels as security, or maybe not.

Now Altamont Pass is a much quieter place, the site of what was once the largest wind farm in the world. As we drove past it on a winter afternoon, not one of the 4,900 windmills was turning. When we came back through Altamont eight days later, no windmill was turning. On the basis of the consistent, persistent cold weather during our eight-day sojourn, the Altamont wind farm probably didn’t produce much, if any, electrical power during that period.

I wasn’t surprised. During our nine years in Livermore, Alice and I could see many of the windmills from our back yard. As often as not, none would be turning, particularly in the morning, in the evening, in the winter, and from my very limited personal observations, at night (it was too dark to view the still windmills except for the few times I drove through Altamont Pass after dark). The reason for the rampant inactivity is quite simple: windmills are powered by the sun creating temperature differentials, and the resultant movement of air masses.

During the day, the San Joaquin Valley warms rapidly, and the Pacific Ocean doesn’t. Warm air rises from the land, and cooler air rushes inland through the Altamont Pass, powering the windmills as it passes. The land cools faster than the ocean after the sun goes down, and the process is reversed – except the cooling is slower, and the air movement is also slower, providing far less energy to move the windmills.

Wind farms like the Altamont Pass are very inefficient, and wouldn’t exist without heavy subsidies and wishful thinking on the part of politicians and environmentalists. The Altamont wind farm only operates at an average efficiency of 22 percent (producing about 125 megawatts from a 576 megawatts capacity). In fact, because so much power is generated by higher windspeed, much of the energy comes in short bursts; half of the energy available comes from just 15% of the operating time.

To an honest engineer, the math is very simple: moving air has a very low energy density and is unreliable – a huge land area is needed to harvest energy from it. The United States is blessed with stronger winds than Europe, and still wind generates only about one percent of our electricity. According to the Department of Energy, wind farms “could generate 20% of US electricity by 2030.” Apparently no honest engineers were consulted before the Department of Energy made this asinine pronouncement. Wind farms will be lucky to stay at one percent, given our current economic downturn.

An honest assessment of wind power is that it can only be relied on to "supply a low proportion of total demand."
When a wind farm is erected, the fossil fuel generator providing power to the area can't be closed and torn down. Based on my observations, and the observations of others, it still has to run almost eighty percent of the time, and that would be true even if the capacity of the wind farm quadrupled, quintupled, or even exceeded ten times the capacity of the old generator. Why? Simple. No matter how big a wind farm you build, when the wind isn't blowing, it isn't generating.

But the need for electricity doesn't wait for the wind to return.

Where will funding for wind farms arise? From the Federal government, running record deficits while over a trillion dollars is going to bail out banks and automobile manufacturers? From the states? California is in a forty billion dollar hole, with deep cutbacks in education and health services, to name just the neediest state programs. From investors? They’ve been eaten alive by the recession, and wind farm investments make sense only if heavily subsidized by the government – and then they still don’t make sense.

The next time you admire a wind farm, chances are that you will be observing wind mills in inaction. If that is the case, think of all the politicians and engineers that have sold their integrity to create an expensive and wasteful eyesore.

One that you helped build, and must subsidize to operate.

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