When two brothers Michael and David Hartkop had the idea to solar-roast coffee beans, they built a backyard concoction with an old satellite dish and broccoli strainer. Nine years later, the Hartkops are on their fifth-generation solar roaster and sell their USDA organic coffee to 60 wholesalers.
Solar Roast Coffee was born in Oregon in 2004. Three years later, the Hartkops relocated to Pueblo, Colo. because of the city’s small size, sun exposure and presence of a university. “Pueblo is a massive recycling area and it’s also very sunny, so you start to see people involved in alternative technology pop up,” said Michael Hartkop. “It’s a fantastic crossroads of America.”
An apprenticed coffee roast master, Michael recognized from the first batch that this eco-friendly method of roasting coffee beans using concentrated solar energy produced a smooth and unique flavor, since the flame never touches the beans. “We use a method called solar aroma roasting,” Michael said. “It’s a slower process and it brings out the natural flavors of coffee without scorching it or burning it, which is common among conventional coffee roasters.”
The solar technique also enhances the coffee’s natural flavor. “By recirculating the air, we’re creating more steam, and that produces beans with a more rounded flavor. This means the sugars caramelize slower, which makes the flavors and finish smooth,” Michael said.
At Solar Roast Coffee, the beans are roasted in small batches to maximize flavor. The first generation roaster, Helios 1, used 100 plastic mirrors to concentrate the sunlight, creating heat to roast one pound of coffee at a time. Helios 4 marked the first large-scale roaster, able to roast 30 pounds of coffee in 20 minutes. This new solar roaster also included a traditional propane heat source that provided the ability to roast coffee on cloudy days. The model used today, Helios 5, features a new design that uses an electric heater powered by photovoltaic (PV) solar panels on the roof of the Pueblo coffee shop. The Hartkops acknowledge that although this design is less efficient than direct solar heating, the rooftop array helps offset the electricity needed to power Solar Roast Coffee’s operations.
The backyard operation has evolved into a café and drive-thru coffee shop in Pueblo, plus a Denver-based mobile truck that travels to colleges and events. In January, Solar Roast Coffee launched its national franchise program, introducing its unique solar-powered roasting opportunity to brokers and potential franchisees across the nation.
Don Carpenter, sales director for the Colorado Franchise Group, which is partnering with Solar Roast Coffee, is optimistic about the solar coffee company’s future.
“Solar Roast Coffee has all the best ingredients of a brand you want to invest in: The store footprint and floor-plan flexibility, with or without drive-thru, allows Solar Roast placements ranging from strip mall locations to free-standing buildings,” Carpenter said in a statement.