Rooftops of solar powered houses are pictured in Ota, 80 km northwest of Tokyo in this October 28, 2008 file photo. One by one, Japan is turning off the lights at the giant oil-fired power plants that propelled it to the ranks of the world's top industrialised nations. With nuclear power in the doldrums after the Fukushima disaster, it's solar energy that is becoming the alternative. Solar power is set to become profitable in Japan as early as this quarter, according to the Japan Renewable Energy Foundation (JREF), freeing it from the need for government subsidies and making it the last of the G7 economies where the technology has become economically viable. (Photo by Yuriko Nakao/Reuters)

In this April 4, 2014 file photo, a community policeman kicks a man who they alledge participated in an ambush against them near the town of La Concepcion, Mexico. The vigilante force was set-up by affected communities opposed to the construction of the La Parota hydroelectric dam. Two vigilantes were injured and one died. (Photo by Bernandino Hernandez/AP Photo)

Rescue workers help the injured at the site of a multi-storey building collapse in the capital Nairobi, Kenya Sunday, January 4, 2015. The residential building in the Huruma neighborhood of Nairobi collapsed on Sunday and according to the Kenya Red Cross, a dozen people have so far been rescued but an unknown number are still feared trapped. (Photo by AP Photo)

Belgian chocolatier Dominique Persoone snorts cocoa powder off his Chocolate Shooter in his factory in Bruges, February 3, 2015. When Belgian chocolatier Dominique Persoone created a chocolate-sniffing device for a Rolling Stones party in 2007, he never imagined demand would stretch much beyond the rock 'n' roll scene. But, seven years later, he has sold 25,000 of them. Inspired by a device his grandfather used to propel tobacco snuff up his nose, Persoone created a “Chocolate Shooter” to deliver a hit of Dominican Republic or Peruvian cocoa powder, mixed with mint and either ginger or raspberry. (Photo by Francois Lenoir/Reuters)

“Adventurers have gone deep underground to discover previously unexplored caves in these pictures. The awe-inspiring snaps show the cavers dwarfed by the huge series natural rock chambers in the Leye – Fengshan Geopark, China. Belgian photographer Francois-Xavier De Ruydts, 33, captured the team of explorers as they trekked through the deep wonderground in January 2014”. – Caters News. Here: Caving expedition in Fengshan, China, Guangxi province. (Photo by Francois-Xavier De Ruydts/Caters News)

A worker holds harvested chillies at a chilli plantation in Pasir Datar Indah village near Sukabumi, Indonesia's West Java province, August 6, 2015. (Photo by Reuters/Beawiharta)

People eat sushi off the body of a model at an opening event of a bar in Taiyuan, Shanxi province, August 22, 2015. (Photo by Reuters/Stringer)

A country music fan cools off in the wind on the second day of the Stagecoach country music festival in Indio, California April 26, 2014. (Photo by Mike Blake/Reuters)