Workers prepare the roof of a house to get installed solar power modules for producing heat on October 15, 2011 in Wessling, Germany. Germany has and is continuing to invest heavily in solar energy, both in the public and private sectors. The German government introduced a feed-in tariff with its Renewable Energy Act in 2000 that guarantees homeowners a minimum rate for selling electricity from renewable energy sources into the nation's electricity grid. (Photo by Alexandra Beier/Getty Images)

A series of Japanese good luck charms, called “Daruma”, are lined up ahead of the major national elections November 9, 2003 in Takasaki, Japan. The Daruma is said to bring exceptional good luck in all walks of life, but is used especially during election time by all candidates. People think that if they face a difficult situation, as symbolized by the doll that returns to its original position when knocked over, they will always bounce back. (Photo by Koichi Kamoshida/Getty Images)

A North Korean soldier looks through a window at Australian Prime Minister Julia Gillard (L) and her partner Tim Mathieson (C) while they visit the United Nations Command Military Armistice Commission (UNCMAC) meeting room at the border village of Panmunjom, between South and North Korea, on April 24, 2011 South Korea. Gillard will visit Japan, the Republic of Korea and China during a bilateral tour of North Asia from April 20-27. (Photo by Jeon Heon-Kyun-pool/Getty Images)

A girl collects drinking water at Dala river outside Yangon, Myanmar March 3, 2016. Some 650 million people, or one in 10 of the world's population, have no access to safe water, putting them at risk of infectious diseases and premature death. Dirty water and poor sanitation can cause severe diarrhoeal diseases in children, killing 900 under-five a day across the world, according to United Nations estimates. (Photo by Soe Zeya Tun/Reuters)

Inmates perform as cheerleaders during a soccer tournament inside the San Juan de Lurigancho prison, in Lima, Peru, Thursday, May 24, 2018. Inmates of 17 prisons, including four for women, participated in the First Interprison World Cup Lima 2018, organized by the National Penitentiary Institute. (Photoby Rodrigo Abd/AP Photo)

A girl poses at an entrance of her house next to a bomb dropped by the U.S. Air Force planes during the Vietnam War, in the village of Ban Napia in Xieng Khouang province, Laos September 3, 2016. From 1964 to 1973, U.S. warplanes dropped more than 270 million cluster munitions on Laos, one-third of which did not explode, according to the Lao National Regulatory Authority. (Photo by Jorge Silva/Reuters)

A woman smokes a cigarette next to man wearing a mask during lunch hour at the central business district in Singapore September 29, 2015. The 3-hour haze Pollutant Standards Index (PSI) reached a high of 173 at 8am on Tuesday, according to the National Environment Agency. Slash-and-burn agriculture in neighboring Indonesia has blanketed Singapore in a choking haze for weeks. (Photo by Edgar Su/Reuters)