Earth Hour

The Las Vegas Strip is seen in the top image just before the lights are turned out for Earth Hour Saturday, March 27, 2010 and after in the bottom image. (AP Photo/Las Vegas Sun, Justin Bowen)

The Shubert Theatre sits with its marquis lights turned off during the Broadway for Earth hour in New York Saturday March 27, 2010. Millions around the world were expected to turn off lights and appliances for an hour from 8 30 p.m. in a gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. (AP Photo/David Goldman)

In this combination, two photos show the Belarusian National Library taken before and after the lights are turned off during the worldwide Earth Hour, a global campaign to highlight the threat of climate change, with lights turned on at top, and below with lights turned off, in Minsk, Belarus, Saturday, March 27, 2010. Many millions of people worldwide are turning off lights and electrical appliances for one hour Saturday night, in a mass gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. Monument of Belarusian enlightener Frantsysk Skorina is on left. (AP Photo/Sergei Grits)

View of Canary Wharf in the financial district of London during the Earth Hour when lights are switched off for an hour in support of climate change, Saturday, March 27, 2010, with the river Thames in foreground. Some buildings are observing the call to observe Earth Hour, while others have left their lights on. Many millions of people worldwide are turning off lights and electrical appliances for one hour Saturday night, in a mass gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. (AP Photo/Sang Tan)

In this combination, two photos show hostel Af Chapman in foreground and background the exterior of the Royal Palace in Stockholm, Sweden, with lights turned on at top, and below with lights turned off, during Earth Hour on Saturday, March 27, 2010. Many millions of people worldwide are turning off lights and electrical appliances for one hour Saturday night, in a mass gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. (AP Photo/Fredrik Persson/Scanpix Sweden)

In this combination, two photos show the City Hall in Oslo, Norway, with lights on at top, and with lights extinguished at bottom, turned off during Earth Hour, March 27, 2010. Many millions of people worldwide are turning off lights and electrical appliances for one hour Saturday night, in a mass gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. (AP Photo / Kyrre Lien, Scanpix)

In this combination, two photos show before, left, and after, at right, showing the effects of Earth Hour, where buildings, boats and Cairo's tower turned off most of their lights, in Cairo, Egypt, Saturday, March 27, 2010. Many millions of people worldwide are turning off lights and electrical appliances for one hour Saturday night, in a mass gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. (AP Photo/Amr Nabil)

A view of the historic Trevi fountain with all illuminations switched off, in Rome, Saturday, March 27, 2010. Many millions of people worldwide are turning off lights and electrical appliances for one hour Saturday night, in a mass gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. (AP Photo/Angelo Carconi)

This combination photo shows Antoni Gaudi's La Sagrada Familia church with its lights on and after being turned off to mark Earth Hour in Barcelona, Saturday, March 27, 2010. (AP Photo/David Ramos)

People seen standing with candles at the beach of Muizenberg situated on the outskirts of Cape Town, South Africa, Saturday, March 27, 2010. People took part in Earth Hour celebration by taking part in a soccer game with a luminous ball and standing with candles. (AP Photo/Schalk van Zuydam)

A couple kiss as the Eiffel Tower is shown just after the 20,000 bulbs illuminating the tower went out, Saturday, March 27, 2010. Many millions of people worldwide are turning off lights and electrical appliances for one hour Saturday night, in a mass gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. (AP Photo/Thibault Camus)

This combination picture of Moscow panorama with the Moskva river and Hotel Ukraine at right taken before and after the lights are turned off during the worldwide Earth Hour, a global campaign to highlight the threat of climate change in Moscow Saturday, March 27, 2010. Millions of people worldwide were switching off lights and appliances for an hour from 8 30 p.m. in a gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. 2010 was the fourth annual Earth Hour, organized by the World Wildlife Fund. (AP Photo/Sergey Ponomarev)

Cars pass in front of the Greek Parliament with its lights dimmed during Earth Hour in Athens, on Saturday March 27, 2010. In Greece, floodlights in several monuments and public buildings were switched off for one hour at 8 30 p.m. local time. Thousands of businesses and municipalities also dimmed their lights. (AP Photo/Thanassis Stavrakis)

A man holds his two months old daughter Vibhuti Shelar during a candle light rally for Earth Hour when the lights are turned out in an hour long gesture to be repeated by millions of people around the world who are calling for a binding pact to cut greenhouse gas emissions, in Mumbai, India, Saturday, March 27, 2010. Buildings in some 4,000 cities in more than 120 countries are expected to unplug to reduce energy consumption and draw attention to the dangers of climate change, with participants turning off the lights when the clock strikes 8 30 p.m. local time. (AP Photo/Rajanish Kakade)

Models display creations by Septwolves designer collection stall in conjunction of Earth Hour during China Fashion Week in Beijing, Saturday, March 27, 2010. The words on top right reads love planet, shut down power for one minutes. (AP Photo/Andy Wong)

These combo photos show a general view of commercial buildings before (top) and after (bottom) turning off lights at Hong Kong's central district Saturday, March 27, 2010 to mark the annual Earth Hour. Earth Hour takes place worldwide at 8.30 p.m. local time and is a global call to turn off lights for 60 minutes in a bid to highlight the global climate change. (AP Photo/Vincent Yu)

Tokyo Tower is lit orange in the Tokyo skyline before turning off its lights Saturday, March 27, 2010. Tokyo Tower was turned off the lights later for an hour during the annual Earth Hour, calling for a binding pact to cut greenhouse gas emissions. Buildings in some 4,000 cities in more than 120 countries were expected to unplug to reduce energy consumption and draw attention to the dangers of climate change, according to organizers. (AP Photo/Hiro Komae)

The Sydney Opera House, left, and the Harbour Bridge have their lights that usually have structures well lit at night turned off in Sydney, Saturday, March 27, 2010, as part of Earth Hour. Millions of people in more than 100 countries are expected to dim the lights in what has become an annual gesture against global warming. (AP Photo/Rick Rycroft)

In this combination of two images, the landmark India Gate is seen lit, top, and then in darkness as the lights are turned out for one hour to mark Earth Hour, in New Delhi, India, Saturday, March 27, 2010. Buildings in some 4,000 cities in more than 120 countries were expected to unplug to reduce energy consumption and draw attention to the dangers of climate change, with participants turning off the lights when the clock strikes 8 30 p.m. local time. (AP Photo/PTI, Aman Sharma)