If the World Cup were a contest of energy efficiency instead of soccer acumen, which country would win?
Using conservation as a baseline, cloud-based software provider Opower compared a few of the 2014 World Cup contenders, breaking down how each country would fare in head-to-head matchups on environmentally friendly energy policy.
The firm did a similar exercise for this year's Super Bowl—correctly predicting the Seattle Seahawks would emerge victorious against the Denver Broncos. In an interview, Opower said it uses sports themes to package information on energy efficiency, in order to "capture people's attention and motivate them to save energy," said Barry Fischer, the study's head writer.
In its list, Opower took the actual matches of Brazil versus Mexico, Japan against Colombia and Germany versus the United States, declaring the winner based on how well each conserved power and reformed its energy sector. Under those criteria, the study's result foreshadowed the Brazil-Mexico match that ended in a tie.
Both countries "are taking significant measures to become energy efficient, but are facing big challenges," Fischer told CNBC. "They have a growing middle class that's using more electricity and has infrastructure limitations."
Opower points out that Brazil's rapid growth has been accompanied by a big jump in middle-class citizens who consume more energy. Latin America's largest economy generates nearly 80 percent of its power via eco-friendly hydroelectric dams, yet those efforts have been complicated by a surge in demand for electricity, as well as a dry spell that has depleted reservoirs.
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Conversely, Mexico has a profile similar to Brazil's: rapid growth and a large group of the upwardly mobile middle class that is drinking up power. Broad efforts to reform its energy sector are laudable, Opower writes, "but what it means for energy efficiency at this point is not entirely clear."
When Japan squares off against Colombia next Tuesday, Opower believes it's the world's third-largest economy that will have the edge based on energy efficiency.
After the 2011 disaster at Fukushima, the country has replaced nearly half its nuclear power through energy conservation, the firm notes. According to International Energy Agency data, Japanese households use less than half of the power eaten up by the U.S.—the world's largest energy consumer.
Compare that to Colombia, which Opower calls "an ambitious up-and-comer" that has targeted an energy savings goal of nearly 15 percent by next year. Although the country has passed a swath of new clean energy regulations, the Andean nation isn't quite yet in Japan's class, according to Opower.
Next Thursday, underdog Team USA will face off against Germany. Opower sees this as a proxy battle between Germany's wide-ranging energy initiatives, and the recent U.S. move to regulate power plants—the country's first ever to curb emissions on electricity generators.
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"Like in [soccer], the U.S. possesses huge untapped potential to save energy" that could produce millions in carbon emissions cuts and more than $2 billion in savings, Opower says.
At least in this match, however, don't expect the world's largest energy guzzler to pull off a miraculous upset like it did in Brazil this week against Ghana's Black Stars.
Opower writes that Germany's recent conservation efforts—including a new residential skyscraper that the firm calls "a monument to energy efficiency"—give Europe's largest economy a definitive edge.
—By CNBC's Javier E. David