There's more than energy conservation and saving our planet at stake when Oakville joins the world in the Earth Hour challenge this weekend.

Also up for grabs come Saturday night at 8 p.m. are bragging rights for either Oakville or Burlington. The two communities' mayors -- Rob Burton and Cam Jackson-- agreed on a friendly wager to see which municipality could reduce its hydro use by the greatest amount.

Although the challenge to have our entire town turn off its lights for one hour starting at 8 p.m. is largely a symbolic gesture, the idea is to spread the message about the importance of reducing our carbon footprint.

Last year, in Australia, more than two million homeowners and businesses in Sydney -- including the world-famous Sydney Opera House -- turned off their lights for one hour.

The gesture created a 10 per cent reduction in hydro use while preventing about 25,000 tonnes of carbon dioxide -- about the equivalent of taking 50,000 cars off the road for one hour -- from being released into the atmosphere.

This year's World Wildlife event is expected to see as many as 20 major cities across six continents helping to spread the message that we can all impact climate change in some way. The objectives of Earth Hour are simple: