WIND ENERGY IS FICKLE
ALWAYS READ THE FINE PRINT. PART 2
Who says wind power is reliable? Well, of course wind power devlopers say it is, so do wind power equipment manufacturers and advocates. Why would they say otherwise? What else would they say? Perhaps, Oh, yeah, these turbines break down a lot but even when they are running just fine the wind itself is a problem....you know...either too much or not enough or just the right speed but at times when no one needs the energy they produce. Even Ken "Slick" Salazar knows better than to say such things. I mean, his hat is too tight, but not that tight.
For as long as wind power has been offered as the savior of our energy situation, clean and cheap, the facts of wind power have been carefully edited from the public conversation. Slick Salazar actually said in Boston as he announced his approval of Cape Wind that the project would improve the reliability of our electric system. It is often said in print and elsewhere that wind power will stabilize our energy supply and our energy prices. Of course, anyone can claim to be stabilizing prices by simply charging three times what everyone else is charging and doing so forever. The price may be high, but it is stable, not subject to the fluctuations that cause prices to rise...and fall.
There are at least three aspects of wind power's unreliability that catch my attention. The first, particularly true for offshore wind, is its innate mechanical quirkiness. Offshore wind turbines are notoriously prone to breakdowns. They seize, stall, burn, fling parts far and wide and sometimes simply stop. In fact, offshore wind turbines are five - to - six times more expensive to maintain than land based wind turbines, according to widely available information. Why is this? Could it be the salt in the air that corrodes virtually everything made of metal? Or, perhaps it is the rapid fluctuations in air tempreature commonly found over large bodies of water, or perhaps the fluctuation of winds, again over large bodies of water. Starting and stopping a mechanism that weighs hundreds of tons and is rated in the thousands of horsepower (1333 HP/MW) can strain even the stoutest transmissions, gears, blades and shafts. These problems are only made worse when one considers how difficult it is to reach and service these 400 + foot tall beasts in bad weather, when breakdowns are the most likely.
A second problem is the simple fact that wind is fickle. Wind turbines function only within a certain range of wind speeds. Obviously some wind is required, but generally winds over 50 MPH or 55 MPH will cause a turbine to shut down. Wind energy is a very site-specific technology. Good wind conditions in one location may not be found even at a site nearby. Anyone who is familiar with Atlantic coastal waters knows how fickle conditions can be. Cape Wind associates claims to have been recording wind data accurately for six or more years, but they refuse to make their wind data public and there is some doubt about the accuracy, some say honesty, of the data they have posted at various times on their website. One claim is that on a particular Thanksgiving day when Cape Wind claimed it would have been generating at near full power winds on Nantucket Sound gusted to 92 MPH. All turbines would have been shut down.
Another problem is that here on Cape Cod we experience summer "dog days." These are very hot, humid days when demand for electricity soars to annual high levels but there is often no wind. Power shortages are not uncommon as the grid strains to satisfy demand and electric companies are forced to buy additional electricity on the spot market at huge premiums. There would be no wind energy produced offshore on such days, even though the demand would be at its highest levels. So much for making our electric supply more reliable or stable. Similar lulls in wind occur during the winter, offshore after storms. Again, demand rises due to increased heating of buildings and the shorter daylight hours call for more lighting. Also in winter the northern Atlantic coast also sees very high winds combined with extreme cold, thus producing increased demand under conditions less than ideal for offshore wind turbines. Cape Cod experiences frequent winter gails of 60MPH and more.
Perhaps the most elegant fact of wind power's erratic nature is what happens at night: often very stable wind speeds in just the right range for optimum wind energy generation. The problem is that on most nights when these wind conditions are found, demand is low due to the fact that people are sleeping, stores and offices are closed and the world is using far less electricity than during the day. But those turbines will be spinning beautifully, producing energy we can neither use nor store.
The third and final fact that makes wind power less appealing in fact than in theory is that it will always require back-up. Without redundancy wind power will raise havoc with the grid. Every megawatt of wind generation capacity must be matched with an immediate and reliable source of back up power. This means that we will require 54 gigawatts of back up power to match the desired wind power capacity Slick and his Beltway Boys are planning. Any wind power producer who wants to secure a power purchase agreement will have to guarantee certain quantities of power and this means back up power is a must just to maintain some stability on the price side of the energy market. So, how many conventional plants will wind power shut down? No one has calculated this yet....folks have been too busy bragging to do the sort of planning that is needed. As the BP Deepwater Horizon disaster has shown, Slick does not do well with details.
Add to these three problems the fact that adding large new power loads to our present electric grid will call for massive grid upgrades. All this will cost billions of dollars. A report compiled for the New England governors quotes a figure of $10 billion for needed upgrades. The Massachusetts share of that total is approximately $4.4 billion. It is not yet known how much will be needed for the grid upgrades required up and down the Atlantic coast to accomodate 54 gigawatts of new but fluctuating power.
Yup, always read the fine print. Of course, first there has to be somneone willing to provide it.
Copyright 2010 by Peter A. Kenney