Among the many challenges companies face in their sustainability efforts is one of the most persistent and hardest to overcome: Getting your employees, and customers, to change their own behaviors.

This lack of engagement with green ideas, products and services has killed many a green initiative, and is one of the things that closed the coffin for both Google and Microsoft's home energy management businesses, something that led GreenBiz contributor Truman Semans last week to opine on three possible solutions to the engagement dilemma.

One of the most obvious solutions -- making behavior change fun -- has also been one of the hardest to successfully enact. But yesterday, I got a chance to learn about how one company is marrying social media, gaming and education in a new campaign that is already showing signs of success.

SunPower Corp., the San Jose-headquartered designer and manufacturer of high-efficiency solar panels and arrays, launched last month a Facebook contest to educate consumers about solar energy. The company hopes the campaign will reach people it wouldn't normally reach -- especially if the campaign goes viral -- while also beefing up its online community and planting the idea of rooftop residential solar in the minds of potential customers.

"It is basically a way for us to engage with our audience in a fun and meaningful way," Belis Aksoy, SunPower's Marketing Manager, New Media, said during a press event Monday. "The Solar Discovery Game is highly social and shareable. It resides on Facebook, where contestants can share their experiences via the game, and at the same time, spread the word to their friends and family."

SunPower believes the contest is the first of its kind for the solar power industry. The contest's grand prize for the contestant who earns the most points is a SunPower solar energy system for their home worth up to $25,000. There will also be random drawings for more than 60 prizes from the company and its affiliate partners, including airline tickets to Hawaii and museum passes.

Contestants earn points and virtual badges by answering a series of questions about solar power that range from easy -- such as the meaning behind the acronym "PV" -- to difficult, such as the number of solar panels installed by a New Mexico family who made a documentary about their SunPower system.

The contest not only gets users clicking through its website and learning about the company, it also helps SunPower dispel misconceptions about solar energy, such as the sturdiness of the solar panels, which have been shown to withstand golf ball-sized hail. Contestants may turn into customers by using tabs for an instant solar quote and free home evaluation.

On average, contestants spend 18 minutes on the site. Success is also measured by the number of people SunPower can reach and educate as a result of the game, Ingrid Ekstrom, SunPower's director of corporate communications, said in an email. "In the first three weeks since we launched the game on June 21, SunPower’s Facebook community grew by 67 percent."

SunPower's online community increased to nearly 9,000 after the contest's launch, Aksoy said. The Solar Discovery Game has also attracted participants from nearly every state in the U.S., and although the company expected many players under the age of 24, the game is also attracting more mature players, which mirrors something else Semans noted last week in his blog about engaging consumers on energy management products:

"Check out these stats: Farmville has more than 39 million monthly users (9.6 million active daily). Guess what the average user profile is? Teenage male? Not! Would you believe: middle-aged woman? That's right, and those same women are key decision-makers on residential energy use and spending. Why do they play online games? One of the main reasons, former Zynga CFO Mark Vranesh told me recently, is community. It's a platform for social interaction. So, imagine instead of an energy management dashboard that you use in isolation, customers get an interactive social game with energy inside?"

We're going to check with SunPower at the end of the campaign to hear about how the contest went and what the company learned. Stay tuned.