Google’s out to prove that king coal won’t permanently have a financial advantage over renewable energy.

High costs of renewable energies (such as solar, wind and thermal) compared to electricity created by burning coal, has been a huge hurdle for the clean energy sector to overcome. Traditional wisdom has it that renewable energy can only be a niche player in the power markets.

But Google set out in 2007 to disprove this wisdom, and this week, the search engine company said it expects to buy all of its electricity from renewable energy suppliers at prices cheaper than electricity provided by coal-fired power plants.

Google’s so-called green energy czar, Bill Weihl told Reuters news service it’s “even odds, more or less” that Google will run totally on clean energy that’s cheaper than coal within three years.

If Google pulls this off, it could open the door for all sorts of companies and industries to switch to clean energy, based on renewable sources, which would make it much easier for the U.S. to reduce greenhouse gas emissions.

The bold goal of replacing coal-fired electricity is part of Google’s green goals to reduce its carbon footprint, adopt efficient computing and help employees go green. Click here for Google’s green plans.

The company’s story is here.

Google has also developed a smart power meter that gives consumers the ability to monitor their daily electric power usage on their home computers. Google has partnered with eight power companies to test the Google Powermeter so homeowners can control usage and cut costs.

Tags: coal-fired, Google, greenhouse gas emissions, renewable energy, solar, thermal, wind