Eco Roast – The Solar Roaster

Craft & Design Energy & Sustainability
Eco Roast – The Solar Roaster


Photograph by Thomas Hartkop

Mike and Dave Hartkop had been eyeing their father’s abandoned satellite dish in the garage for years. But it took an especially productive night of brainstorming at the local pub to come up with an idea that tapped into their respective interests in coffee and solar energy to put that dish to good use. The Solar Roaster was born.

The first version of the Hartkops’ solar coffee-bean roaster was built by attaching several hundred homemade plastic mirrors to the frame of the 10- foot satellite dish. Dubbed Helios, the roaster took about two months to complete and looked more like something off the set of Battlestar Galactica than a piece of equipment you’d find behind a coffeehouse.

The Hartkop brothers make a good team for a solar coffee-roasting venture. Mike is the coffee fiend, developing the organic solar-roasted flavors and handling the business details, while Dave is the designer and engineer for their unique roasters. As the solar roasters use no fossil fuels or electricity, Mike likes to claim they’ve found the most environmentally friendly method of roasting coffee beans in the world.

Dave has been building solar concentrators for the past five years. He’s completed two solar coffee roasters and is working on the third and biggest version to date. The solar roasters are getting progressively more efficient, complex, and expensive (they retired Dad’s satellite dish after the first version). The hardest part has been building the miniature drum roaster heads, which have to operate with very limited electrical power, handle vibration and wind, and operate when tipped to nearly 90 degrees when tracking the sun.

Helios 3 will be their first mobile solar roaster. The Hartkops plan to take Helios 3 on the road to festivals and shows (and to follow the sun in rainier months).

“I’m hooked on the concept of roasting coffee because the product is instantly accessible by the common person,” Dave explains. “It is not an abstract figure given in kilowatt-hours, which supposedly reduces X pounds of fossil-fuel pollution. Solar Roast Coffee reduces those pounds and it tastes good!”

From the column Made on EarthMAKE 7, page 22 – Bruce Stewart.

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Craft & Design
Made On Earth — Eco Roast


Mike and Dave Hartkop tapped into their respective interests in coffee and solar energy to put their father’s abandoned satellite dish to good use.

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