Sunday, March 8, 2009
The advocates of wind generation see it as free energy. The more the merrier. Most have no comprehension of how a grid works and what is needed to deliver reliable power to the end users. They don’t understand that when you turn on a light bulb or when a stamping plant in Michigan, using gobs of power, begins squeezing a body panel into shape, there must be enough electricity on line at that moment to satisfy demand. This is called the baseload, and is usually estimated a day in advance for various time periods. If the grid comes up short, voltage drops, turbines bog down and get out of phase. If more electricity isn’t put on line quickly, brownouts occur. If voltage drops below 107 volts, electric motors for air conditioners and refrigerators, for instance, can be damaged and the grid must access reserves or shed load. The grid’s system operator must maintain reserves at least the size of the largest generator on the grid, in case one goes down. Reserves can be supplied from the grid itself, from a neighboring grid or purchased on the day ahead spot market. Baseload power is supplied by low cost generating systems, most often nuclear and coal. Nuclear is generally operated at full power, shutting down only for maintenance, refueling and unscheduled outages. According to the government’s Energy Information Administration, nukes average 92% annual capacity load factor. More expensive electricity is brought on line as demand warrants. Wind power isn’t a good match for baseload management, but regulatory requirements mandate it be given priority. Wind has a problem. It is an intermittent source of electricity. It isn’t necessarily there when you need it. Here’s an example of 660 kW wind generator located at the Massachusetts Maritime Academy at Bourne. It reports current, daily, weekly, monthly and annual output data online in real time. Click here for current data from this very interesting website. Because of its intermittency, wind power must be backed up by conventional thermal power. This means fossil fueled plants can’t be dismantled as wind power capacity is put in place. There are just times when there is no wind over vast stretches of our country. Just after Al Gore made his energy speech last July, I checked the wind maps of the eastern US. There was no wind over 10 mph (the threshold for wind generation) anywhere on the east coast, and most areas were flat calm. Other than pumped water storage, there is no economical way to store this electricity. There are only 31 pumped storage facilities in the US and all their capacity is spoken for. The prospect for expanding that number is unlikely. If we wish to remain a competitive industrial nation, we must have reliable power at rates comparable to nations competing against us. An example is the aluminum industry. It takes 5 to 6 kWh of electricity to produce a pound of aluminum. Electricity is the most expensive component in the process of converting bauxite to alumina to metallic aluminum. The current market for aluminum is just under 60 cents a pound. To be competitive, US producers must have access to 5 cents/kWh or less electricity. And they must have it 24/7, not when the wind blows. Only nuclear and coal can do that. If we drive costs over that, production and jobs will move to China or Russia. The EU is facing the same problems and will delay cap and trade targets for their aluminum industry. Costs and reliability of our electricity must considered if we allow Asian competitors to continue their carbon emissions. All we will do is transfer our industries to them and world carbon emissions will remain the same.