A combination picture shows Hong Kong's central financial district's (L-R) Bank of China Tower, Cheung Kong Centre, HSBC headquarters, Standard Chartered Bank and Legislative Council before (top) and during Earth Hour, March 26, 2011. Lights started going off around the world on Saturday in a show of support for renewable energy, given added poignancy by Japan's nuclear disaster which raises doubts about nuclear power as a possible solution. Landmarks in thousands of cities, from Sydney Harbour Bridge to the world's tallest building, the Burj Khalifa in Dubai, will turn off the power for Earth

A combination picture shows Hong Kong's central financial district's (L-R) Bank of China Tower, Cheung Kong Centre, HSBC headquarters, Standard Chartered Bank and Legislative Council before (top) and during Earth Hour, March 26, 2011. Lights started going off around the world on Saturday in a show of support for renewable energy, given added poignancy by Japan's nuclear disaster which raises doubts about nuclear power as a possible solution. Landmarks in thousands of cities, from Sydney Harbour Bridge to the world's tallest building, the Burj Khalifa in Dubai, will turn off the power for Earth

REUTERS / Alamy Stock Photo

Image ID: 2D0CN95

A combination picture shows Hong Kong's central financial district's (L-R) Bank of China Tower, Cheung Kong Centre, HSBC headquarters, Standard Chartered Bank and Legislative Council before (top) and during Earth Hour, March 26, 2011. Lights started going off around the world on Saturday in a show of support for renewable energy, given added poignancy by Japan's nuclear disaster which raises doubts about nuclear power as a possible solution. Landmarks in thousands of cities, from Sydney Harbour Bridge to the world's tallest building, the Burj Khalifa in Dubai, will turn off the power for Earth Hour, the fifth such event promoting a sustainable future for the planet. REUTERS/Bobby Yip (CHINA - Tags: ANNIVERSARY CITYSCAPE ENERGY ENVIRONMENT BUSINESS TRAVEL)