The federal wind production tax credit is set to expire after 20 years of taxpayer handouts. While the industry has recently used job loss claims to defend extension of its subsidy during this down economy, the entire premise of wind energy rests on a faulty environmental assumption: Wind power is ostensibly worth subsidizing because it reduces carbon emissions and has a lighter effect on the environment than other forms of energy.

Neither claim is true. 

It may come as a surprise to some, but wind power doesn’t actually cut carbon emissions — it increases them. 

Even though the turbines don’t emit carbon, they do lead to more carbon output when they’re connected to the electrical grid. Wind tends to blow least when the demand for electricity is greatest, so it needs to be backed up with reliable conventional sources such as coal, natural gas or nuclear. 

Conventional electricity sources can be programmed to match periods of peak electricity demand — too bad Mother Nature can’t. When the wind doesn’t blow and power plants have to ramp up their production, their level of efficiency drops dramatically. 

Turning power plants on and off makes them emit more carbon dioxide, defeating any environmental gains from using wind turbines in the first place. If you’re concerned about global warming, installing wind power doesn’t actually move you any closer to reducing carbon emissions.

Higher carbon emissions is not the only reason true environmentalists should oppose wind power. Wind turbines also kill birds by striking them with their blades. The U.S. Fish and Wildlife Service estimates that wind turbines kill almost half a million birds per year, including protected species of eagles, raptors, hawks and owls. In the San Francisco Bay Area alone, wind turbines kill about 70 golden eagles each year. The American Bird Conservancy predicts that bird deaths could exceed a million per year if the United States reaches its wind power output goals in the next 20 years.

Even birds that manage to avoid colliding with the wind turbine blades face risks from wind power. Poorly located wind farms hurt birds by disrupting their migratory flight paths and nesting locations. This puts future bird populations in jeopardy, as it threatens their ability to produce new generations.

Birds aren’t the only winged creatures affected by wind power. Wind turbines also lead bats to an untimely demise, but one that may be even more gruesome. Bats are very adept at sensing where wind turbines are located using echolocation, but they cannot detect the plunge in air pressure that’s created when air flows over the turbine blades. When bats fly through this low-pressure area, the air in their lungs quickly expands and their lungs explode. The bats die from internal hemorrhaging, a condition known as barotrauma. 

Considering all the environmental drawbacks to wind energy, it remains a puzzle why it is widely celebrated as a “green” solution to our energy needs.

If the left were truly in favor of protecting the environment, then it should be urging Washington to end the wind production tax credit. It seems that it’s more interested in protecting Big Wind instead.

Christine Harbin is a policy analyst at Americans for Prosperity.