Point Defiance Zoo in Washington was in the process of an aquarium expansion project to build a new shark tank and sea life aquarium. The construction company tasked with the build needed to find a way to heat the interior of the all-concrete structures to the required 65°F. On top of getting clean, warm air into the area, the equipment would need to keep noise levels low enough so as not to disturb the sea life or visitors. What’s more, they needed something that would be fuel efficient and capable of running for an extended period of time without being constantly refueled.