The project is located near PPM Energy's existing 150 MW Shilo 1 plant in the Montezuma Hills wind resource area in Solano County where hundreds of older generation turbines already turn. Enxco developed Shilo 1 before selling it to PPM energy.
Following over a year of extensive review with Solano County to approve permitting, the military filed a midnight-hour complaint in the last week of March, just before a final vote from regulators, says Enxco's Greg Blue. "We hadn't heard anything this entire process, nobody was showing up to protest, and all of sudden we hear this thing," says Blue. The Air Force base is the largest employer in the county with about 10,000 staff.
Assuming the county regulators would not grant a permit with the base opposed to the project, Enxco asked for a six month extension to work co-operatively with the military to find a solution, says Blue. "They have never come out and opposed the project. They are a big supporter of renewable energy. They're not trying to kill the project, they just have concerns."
Those concerns, says the AFB's Lieutenant Colonel Shawn Nelson, stem partly from the base undergoing a switch from analog based radar to a new digital radar system. He says the existing turbines near the base -- little more than five miles away -- already create false images, called ghosting, and images of existing aircraft are regularly lost. "My opinion is that this is not a new issue, it's something that can be overcome," says Nelson.
Technology solutions elsewhere in the world have involved software upgrades to the radar systems that compensate for the effect from nearby turbine operation. But Nelson believes the wind industry needs to do more. "There's going to have to be a hard look from wind turbine manufacturing, there are going to have to be technologies that absorb or reflect radar with stealth technology," says Nelson. "That's something the two industries will have to work out."
Nelson is positively inclined. "I think everybody is taking a step back and taking a harder look. The next time we meet will be in October. We're working with Enxco. We do want to see these move ahead."
The project is to be the first wind plant in the US to use turbines from Germany's Repower, according to Blue. Seventy-five 2 MW turbines have been bought by Enxco from Repower. FPL Energy was also interested in a smaller, commercial scale project in the area, but Nelson says following these radar concerns, it has diverted its interest and turbines elsewhere leaving the problem with Enxco alone.
Air Space Policy Officer Lieutenant Colonel William Crowe -- who months ago acted as a formal liaison officer between wind developers and the military on a national level -- says he cannot comment on the situation in Solano County.