Imposing tariffs on solar components imported into the U.S. will drive up prices for solar developers. It could also cost U.S. taxpayers as much as $1.23 billion.

The U.S. offers incentives to encourage people to use clean energy, paying owners of solar-power systems a tax credit equal to 30 percent of the total installation costs.

More expensive panels leads to higher costs, and that means taxpayers could be on the hook for about $1.23 billion more, according to an estimate from Cowen & Co. analyst Jeffrey Osborne.

That assumes that current forecasts for 2018 installations hold steady at about 10.3 gigawatts, estimates from before the before the U.S. International Trade Commission ruled 4-0 Friday in favor of imposing tariffs. The result could be fewer projects built at the higher costs, said Nathan Serota, a Bloomberg New Energy Finance analyst. Anything that artificially raises the cost of solar increases the amount of the tax credits that help pay for it.

“The U.S. taxpayer gets less bang for the buck,” Serota said in an interview.