Homero Aridjis & James Ramey for Huffington Post:  President-elect Donald Trump has repeatedly called for Mexico to build a wall between our countries. There is indeed a way that Mexico could create a barrier between the U.S. and Mexico, one constructed exclusively on the Mexican side, with substantial benefits for both countries and the planet: a solar border.

Sunlight in the northern deserts of Mexico is more intense than in the U.S. Southwest because of the lower latitude and more favorable cloud patterns. And construction and maintenance costs for solar plants in Mexico are substantially lower. Thus, building a long series of such plants all along the Mexican side of the border could power cities on both sides faster and more cheaply than similar arrays built north of the border.  

Solar energy is already being generated at lower prices than those of coal. With solar plants along vast stretches of the almost 2,000-mile U.S.-Mexico border on the Mexican side, a new high-voltage direct-current (HVDC) grid could be set up to transmit energy efficiently from that long, snaking array to population centers along the border. HVDC power lines lose exponentially less energy over long distances than traditional power lines.  Cont'd...