Earlier this week, the Earth Day Network announced the 'Green Cities' challenge, asking communities worldwide to reduce their dependence on 'dirty' energy - electricity produced using fossil fuels. Now Washington D.C.'s Georgetown University is making the challenge more enticing, with a $5 million USD reward for any U.S. town or city that devises the best program to reduce energy consumption.

The idea is the brainchild of the University’s physics professor, Francis Slakey. The adventurer who has climbed the earth's tallest peaks and surfed its seven seas, says that his extensive travels made him acutely aware of the many global challenges, humans face. Being a physics professor, he decided to focus on energy as the one to try tackle.

So in May 2012, he began brainstorming with the other faculty members on how to encourage Americans to increase energy efficiency. After much deliberation, the group decided that the best way to motivate people was by offering a financial incentive. However, while the $5 million USD prize money is substantial, it is not enough to make a difference to large cities like New York or Los Angeles. Hence, the team decided to open the challenge to communities with smaller populations of between 5,000 - 250,000 - ones to which the money would mean the most. Also, given that they account for 70% of the U.S. population, it would give most Americans a chance to participate, and make a difference.

The challenge, which was announced on April 23rd, gives any interested city or town two month to enroll. Than begins the two-year quest to reduce their energy usage. So far, 50 communities all the way from Fremont, CA to Atlantic City, NJ, have stepped up to the challenge. Though the $5 million USD is certainly a draw, they all also have other reasons for joining. Some like Oberlin, Oh want try address climate change at a local level by becoming carbon neutral. Others like Fairbanks, AK, simply want to reduce energy costs.

Slakey says that the winning community, which will be announced in 2017, will be judged on the total reduction in electricity and natural gas usage, per capita. In order to make it equitable, local climate will also be factored in. The other things that will play an important role is how the city encourages community members to join and most importantly, if their success can be replicated in other parts of the country and possibly, even the world.

As for the $5 million USD prize money? Though the University does not have it yet, they are confident that they will be able to raise it from sponsors. In fact, they are hoping to exceed the goal so that they can add category winners - like selecting the city that does the best job of addressing the energy needs of low-income people.

The best part is that while everyone may not receive the $5 million USD, they will all emerge winners, since even small lifestyle changes will go a long way in helping control climate change at a local level and also help residents save thousands of dollars in energy costs. Ready to sign up your community? Check out guep.org to find out how.

Resources: businesswire.com, news.yahoo.com