In California, where the wind boom of the early 1980s was followed by a global oil glut and energy price collapse that stalled new installations in the 1990s, changes are afoot, as many 25- to 30-year-old wind turbines are being removed and replaced by newer machines that are much larger and more productive.
For example, an enXco spokesman said in announcing the purchase of new wind turbines for repowering a Solano project, "We are pleased to be able to implement today's state-of-the-art turbine technology to achieve more than four times greater capacity and nearly 10 times more energy with minimal addition in land resources." In that project, 235 old 100-kilowatt turbines remaining from a 25-MW wind farm installed in 1989 are being replaced by 50 modern 2.05-MW machines totaling 102.5 MW in generating capacity (in other words, each new turbine has as much generating capacity as more than 20 older units).
While there are still a number of 1980s-vintage turbines in the three California passes–Altamont, Tehachapi, and San Gorgonio–and Solano County, where the first commercial wind farms were installed, many are scheduled for replacement (wind farm "repowering") during the next few years. NextEra Energy and enXco, which own thousands of turbines in Altamont Pass and Solano, are repowering many today. According to AWEA's Industry Data team, some 1,500 machines have been removed to date.
Even though they were designed and built in the early years of the modern wind industry, the 1980s turbines have performed well, enduring some of the most energetic wind regimes in California for nearly three decades. But there are limited wind resource areas in the Golden State, and it’s more economical to remove old machines and replace them with new ones than to leave hillsides in windy areas full of unused machines. Since these areas have harnessed the wind for such a lengthy time, developers know what generation to expect from installing new turbines.
In Hawaii, wind farm operator Apollo Energy recently announced that turbines from the Kamaoa wind farm on the Big Island's South Point are being dismantled. In an exception to what is happening elsewhere, there are no plans to replace the South Point facility, but rather to use the area for cattle ranching.
What's happening to the old machines? According to one knowledgeable industry source, many parts from the old turbines can actually be sold to companies that are still operating turbines of the same vintage. Towers can be sold for scrap. The parts that can't be salvaged include the fiberglass blades, which require "special landfilling," and some parts that are coated with hydraulic fluid and would cost more to clean than their salvage value. Those parts also go to the landfill. There is nothing that would be classified as either hazardous or toxic under RCRA (Resource Conservation and Recovery Act), the federal statute that applies.
Both in Solano and elsewhere, the source said, the combination of the turbine's salvage value plus return of the security posted when the turbines were installed has proven sufficient to cover decommissioning and removal of 1980s-era machines.
At the same time, the fact that many wind turbines–both the old U.S. units and machines from Europe, where installations continued through the 1990s–are reaching the end of their serviceable lives has not escaped the notice of entrepreneurs. In Europe, some fiberglass blades from decommissioned wind turbines are being used as raw materials for innovative children’s playgrounds, while there is an American startup that has announced it intends to make a business out of recycling wind turbine blades, so many blades may not wind up in the landfill after all.
With regard to the ultimate fate of the more modern turbines being installed today, similar considerations apply. A recent detailed study of decommissioning prospects for one modern wind farm in West Virginia estimated the salvage value of the project's turbines at $2.8 million, about $39,000 more than the cost of dismantling them.