With new technological developments and greater demand, the costs will only continue to go down, which creates an economic incentive for the use of these technologies. This holds true even in places where coal is cheap and plentiful, like Texas. In Michigan, coal-fired plants are closing, mainly because they have outlived their useful lives and are expensive to run. They are not being replaced by other coal plants, but by natural gas and renewables. The economic case for renewables will keep the market for it healthy and vibrant no matter what the new administration does.
Link: Renewable energy poised to thrive under any White House