U.S. President Donald Trump has reportedly suggested using solar panels as a way to get Mexico to “pay” for the proposed border wall between the two countries. While far from firm plans, these could include either: the U.S. adding panels and selling the electricity to Mexico; or Mexican utilities installing panels and paying for use of the wall as a mounting system. Mexico so far has made only modest investments in solar power, with just 0.8% the installed capacity of the U.S. Imports of equipment suggest an acceleration is not close, with a 3% rise in the past year earlier despite a 17%...