Washington, D.C., USA (GLOBE-Net) – A new study published by the U.S. National Academy of Sciences aims to provide analysis of the environmental impacts of wind energy, both positive and negative.

Wind energy has grown rapidly in North America and worldwide, and has definite positive impacts in certain areas. By displacing for fossil fuels and other energy sources, wind power can reduce greenhouse gas emissions, water pollution, land degradation, and other adverse environmental impacts.

However, others have noted potential negative impacts, such as visual disturbance and incidents of bird fatalities, as well as impacts of installing new transmission lines.

In many cases, these concerns have been used to halt wind power developments, so it is important to be able to evaluate the actual environmental impacts of wind power in order to make sustainable energy supply choices.

There is currently a lack of good tools for governments to evaluate each of these factors, the study found. For example, turbines kill far less birds than vehicles, buildings, and power lines, but good estimates of the actual fatality rates in terms of overall population are hard to establish.

The congressionally-mandated study attempts to evaluate the different categories of environmental impacts from wind power, and provide a framework for project and policy decisions.

Noting that wind power, despite its readily apparent benefits of cleaner air and lower greenhouse gas emissions, is surprisingly controversial, the report’s authors endorse continued expansion of wind power, but with careful evaluation of each project’s impacts.

The report relied on a Department of Energy projection that wind will account for a maximum of 7% of the United State’s electricity in 15 years. The report addressed only onshore projects, although offshore wind farms are under consideration in Massachusetts and other states.

The full study may be read online or ordered here.

Canada currently has 1,492 megawatts (MW) of total installed wind energy capacity, representing just over 0.5% of total energy demand. Provincial governments are currently seeking to put in place a minimum of 10,000 MW of installed wind energy capacity by 2015.

The federal government’s $1.48 billion ecoENERGY for Renewable Power program will provide a payment of one cent per kilowatt hour to producers of renewable energy for the first ten years of a project. A discussion paper released to stakeholders to help develop program specifics outlined that funding would be set aside for 3,000 MW of wind power, and 1,000 MW of other renewables.

CanWEA estimates that wind energy reduced global greenhouse gas emissions by 90 Megatonnes (Mt) in 2006. In Canada, it is estimated that every 1,000 MW of installed wind energy capacity will reduce annual emissions of carbon dioxide by a minimum of 1.2 Mt.