The discrepancy in the extensions of the wind production tax credit (PTC) and solar investment tax credit (ITC), together with other natural tailwinds for PV, will accelerate solar’s inevitable eclipse of wind as the country’s largest source of new power-generation capacity in the coming years. And it’s already affecting the way global renewables developers approach the US market.

While the PTC extension will perhaps allow 20GW of additional wind capacity to be built, there’s no getting around the fact that it will run out in 2019, while the ITC will last until the end of 2021, giving solar an extra two years to hammer down its costs.