The Trump administration is plotting a series of moves in 2018 that could end up harming the wind and solar industries. These include asking regulators to rewrite power market rules, revamping the tax code, and imposing tariffs on foreign-made solar panels.

One of the most closely watched moves will likely involve Suniva Inc., a bankrupt solar panel manufacturer based in Georgia that filed a trade complaint in April. The company, which said it was hurt by cheap Asian imports, has asked Trump for tariffs on foreign panels. The administration has until mid-January to decide.

Solar panel.
Photographer: JG Photography/Alamy

Import duties protecting domestic solar...