Reuters: When remote mining camps in Mongolia's south Gobi desert need energy, they rent diesel generators. But rented solar arrays can provide energy 30 percent cheaper, while producing no carbon emissions, an entrepreneur says. The solar rental model, with no upfront investment costs, makes "a solar farm cheap up front and cheaper to run. The payback time is zero. You immediately start saving from day one,' said Erwin Spolders, whose mobile solar rental company, France-based Redavia, is about to place...