Wind Power is a major success story worldwide, with cumulative capacity reaching 157.9 Gigawatts (GW) at the end of 2009. Turbines reaching 3 or even 5 megawatts (MW) in size dominate the wind power market. Along with these monsters, markets for small wind turbines – machines under 100 kilowatts (kW) in size — have also been chugging along, have reached the 100 MW cumulative capacity milestone in the U.S. last year.

The market for mid-sized wind turbines in North America – as well as the rest of the world — is not a mature segment. Yet a number of recent developments bode well for the long-term viability of mid-sized turbines, a sector that includes turbines 100 kW to 1 MW in size, according to the National Renewable Energy Laboratory (NREL).

NREL recently conducted a detailed, complex study of the market potential for mid-sized wind turbines in the U.S. Sites were screened according to wind speeds, protected habitat, population density, slope and elevation. On top of this natural resource-based screening process was a public policy overlay that took into account wholesale and retail power prices, availability of renewable energy credits (RECs) and other available financial incentives.

The research found that 67,100 sites out of 3.6 million possible sites showed a positive net present value (NPV) for turbines between 10 kW and 1.5 MW under current market conditions – including all applicable state and federal financial incentives. When the market analysis focused on turbines in the 250 to 500 kW range, some 10,407 cost effective sites were identified. In order to compare the existing mid-sized turbine offerings with two advanced “virtual” turbines that were rated 250 and 500 kW (and which also incorporated state-of-the-art turbine technology advances), the number of cost effective sites for the 250-500 kW turbine class jumped to over 200,000 (see below)

The dilemma facing mid-sized wind turbines today is that government subsidy schemes have focused on either multi-megawatt (MW) turbines currently being deployed in utility-scale wind farms or behind-the-meter small wind turbines sized at 10 kW or below. As a result, there is a lack of available mid-sized turbines on the market.

The viability and economics of wind power vary greatly not only by region, but also from site to site within a geographical location. In the U.S. in particular, the market is further fragmented by various state and utility level incentives, regulatory policies, and local permitting requirements. Canada is also moving forward with community wind projects, and includes turbines up to 300 kW in size as “small,” so prospects there will only increase over time. Mexico has excellent wind resources, but the focus on government control of energy resources – and rampant payola – translate into endless delays for the time being.

At present, the best U.S. market for mid-sized turbines is the Northeast, due to high retail electricity rates and net metering policies that are available for turbines up to 1 or 2 MW in size. A leading developer of community wind projects focused on mid-sized machines claims that any facility that consumes between 400,000 and 600,000 kilowatt hours (kWh) annually is a good fit for turbines in the 250 to 500 kW range, particularly large schools, medium-sized factories and municipal waste water treatment facilities. Of course, the Americans Making Power (AMP) Act introduced recently in Congress would change all this, as it would allow all wind turbines up to 2 MW to take advantage of net metering, opening up the superior wind resources of the Great Plains to development for mid-sized turbines.

Photo by Peaco Design Solutions

Peter Asmus is an analyst at Pike Research specializing in renewable energy.