What has happened on El Hierro should also be a cautionary tale for anyone thinking of installing solar panels on their roofs.  A typical system will take ten years to pay back assuming the utility does not buy back your surplus energy, which by the way, most don't and the ones that still do, are quickly realizing they can no longer afford to do so. So, if they don't buy it back , you'll have to buy very expensive batteries to store the surplus electricity and the batteries only last ten years, the same amount of time it takes to pay off your initial investment. By then (ten years later), you're no further ahead and now you'll need expensive maintenance on your ten year old system. There's a good reason most Canadians don't have solar panels on their roofs, it doesn't make economic sense, that's why!