Northern Power began in the early 1970s during the first major oil crisis in the U.S. Now, it is the oldest renewable energy company within the U.S. Its founders rebuilt old wind turbines before adding generators, power electronics, controls and wind turbine design to the company’s core competencies. Today, Northern Power is a venture capital backed growth firm that has the latest permanent magnet direct-drive turbine. Jim Stover, current vice president of global marketing and product management, shares his views on the future of wind energy.
How did you get involved in the renewable energy market?
My interest in renewable energy was spurred while living in Beijing in the late 1990s, when it became clear that the pollution associated with rapid development was ultimately going to impinge on that very same goal of economic development and sustainable growth.
What is the next big thing in wind energy?
Over the past 10 years, turbine manufacturers have focused on building larger and larger machines. We now see an accelerating global interest in “community scale” wind power, where wind turbines are produced and consumed at the retail level in support of local economies and green energy objectives as opposed to wholesale power produced from large wind farms. The turbines are sited in “distributed” fashion to support local power needs. Our Northwind 100 turbine (100kW rated power) is a direct result of that emerging market.
What technology has given the wind energy market the biggest boost?
We are currently seeing movement toward two major trends from a technology perspective. The first is to permanent magnet generators because of their efficiency and reliability. The second is to a direct drive, which refers to the direct connection of a generator to the rotor and the elimination of a gearbox from the drive train.
What’s driving that adoption?
Up until 2009 it was a seller’s market. Rapid overall demand growth led manufacturers to focus on scaling existing proven technology to turbines in the 2MW+ size range and to manufacture as many of those turbines as possible. With the financial contraction, however, we have seen developers shift away from a focus on securing available product to focus more on turbine lifecycle economics.
How do magnet generators increase efficiency and reliability?
Wound rotor generators require excitation of the coils in the rotors. Excitation of these coils not only requires energy, it entails maintenance of a subsystem of slip rings and brushes. Use of permanent magnet generators avoids both of these issues, increasing efficiency and eliminating maintenance costs.