The cost of solar power has plunged over the past decade, making it highly competitive against fossil fuel generation in many parts of the US, and it also often benefits from state mandates. But the pace of development has been dependent on federal government policy, including a tax credit on investment and tariffs on imported panels, which dominate the US market. Levied from February at an initial rate of 30 per cent, President Donald Trump’s tariffs were intended to protect US panel manufacturers.
But the Solar Energy Industries Association, which represents developers and installers as well as manufacturers, said the tariffs had put a brake on investment and cost more than 20,000 jobs. New solar generation capacity coming on line in the third quarter was particularly weak, because it reflected a delay in projects being given the go-ahead late in 2017, as uncertainty over the tariffs escalated and panel prices spiked.
Large utility-scale solar projects were most affected, because their economics are more sensitive to the cost of the panels than for smaller-scale rooftop solar. Colin Smith of Wood Mackenzie, which analyses the data for the SEIA, said that around the end of last year most of the large-scale project pipeline in the US had been put on hold.