ANCHORAGE, Alaska - Thousands of people visit the Alaska SeaLife Center in Seward for a look at Steller sea lions or harlequin ducks.

What's in the basement is almost as interesting.

The SeaLife Center, which combines aquariums with research and wildlife rescue, announced Friday that 98 per cent of its heating and cooling requirements are no longer filled by fossil fuel. The centre is using alternative energy: heat extracted from ocean water in Resurrection Bay.

The heat exchange system is saving money, cutting greenhouse gas emissions and fulfilling the centre's mission of sharing scientific knowledge to promote stewardship of Alaska's marine resources, said Darryl Schaefermeyer, special projects co-ordinator. It demonstrates that seawater is a potential heating source for Alaska, which has more coastline than the rest of the nation put together.

"Simple payback is estimated to be 13 years at the estimated annual savings on electricity of $48,000," he said. "Since starting the system, we have averaged just over $4,000 savings on electrical energy cost per month."

It's used with a seawater system the SeaLife Center installed in 2012.