Visitors to an all glass greenhouse behind the UAA Engineering Building can't help but cozy up to a chunky white brick heater capable of radiating warmth for many hours after its fire goes out.
With just five pounds of scrap wood that burns to ash in less than an hour, circulation channels within the stove capture the hot air long enough to warm the heater's surrounding bricks so they can slowly release their radiant heat.
With $10-a-gallon heating oil common in Alaska's rural communities, this technology, called a masonry heater, might be the path to sustainable energy costs and high-quality heat. Nothing feels better in winter than a warm-to-the-touch radiant-heat floor, right? This is the same idea.
You might suspect some cutting-edge technology just developed to wean us off our addiction to fossil fuels. You'd be wrong. This technology dates back to 12th-Century northern Europe, where talented artisans crafted stoves with intricate channels to trap and hold heat. They aimed to squeeze and recycle every BTU before it escaped out the chimney. The technology is still heavily used in Europe today.
The ancient Chinese used the method, too. They had an even cozier idea. They built their heaters right into the floor and slept on top of them, dating back to the Neolithic Age. New research even shows that early dwellers of the Aleutian Islands had hearths designed to coax hot air into channels around the edges of their subterranean houses.
All these heating processes use the same concept: a quick and efficient fire that traps hot gases long enough to deeply warm the heater's mass, allowing it to relinquish radiant heat over many hours.
Three UAA engineering students -- Cyrus Moghadam, Colleen Dunford and Rebecca Lewallen -- built UAA's chunky white model last spring with a community service grant from Alex Hills, a professor sharing his time between UAA and Carnegie Mellon University.
Three UAA professors of mechanical engineering, Jeff Hoffman, Jennifer Brock and Jifeng Peng, guided and advised their work.
Hoffman, who'd been studying masonry heaters since the '90s and even has a 6,000-pounder warming his Anchorage home, introduced the challenge: Students had to design a heater specific for rural Alaska. Translated, that meant a low-cost design using off-the-shelf components and capable of heating a 400-square-foot building. It needed to be light enough to ship remotely. And the design needed to be simple enough so that someone who'd never laid a brick in his life could build it.
Students did "virtual builds" of three prototypes, using computer-design technology to shave the stove's weight, brick by brick, to just 600 pounds. Computers also allowed them to simplify the air chamber design, Brock said. And Peng, using a sophisticated fluid dynamics simulation, helped the students ensure hot air would swirl around the masonry chamber long enough to thoroughly heat the brickwork.
The professors were pleased: "They really hit a homerun with this one," said Hoffman. Materials cost only $1,200, with weight comparable to just two barrels of fuel oil. Bricks and chimney piping are available right here in Anchorage.
Using the stove takes some adjustments; users build the fire upside down and fire it for only about two hours. A stove door opens into a small square chamber with a grate at the bottom, open to a pan for catching ash. The largest chunks of wood go on the bottom, medium in the middle, with kindling on top. The fire starts at the top and burns downward until only ash is left. The heat-soaked bricks then release their heat for hours, long after the fire is out.
This winter, a new team of undergraduate engineering students will install a traditional woodstove in another corner of the greenhouse, and compare performance between the two. The professors are seeking funds for emissions testing, which can be pricey. They are certain the stove's short burn time, minimal smoke and high combustion temperatures will minimize emissions. They point to a Canadian study that makes the case, and say they'd like to replicate it.
But in the meantime, they want to get these stoves out into rural Alaska.
By next summer, they say they'll be ready to send a team to install the first one. In a teach-one, teach-many model, they plan to post instructions, material lists and distribution details online, free for anyone to use.
All they need now are a few partners to fund some kits, and remote Alaskans can start heating their cabins like the Europeans and Chinese have been doing for centuries.
Kathleen McCoy works at UAA, where she highlights campus life through social and online media.