By John Garvey | Nov 06, 2017
Solar-powered coffee truck
Industry: Food & Beverage
Products: Solar-powered coffee truck
In 2016, Wurtzburg bought a 1978 Toyota camper for $200 and stripped it down to its frame. Michler, his business partner, jokes that it was overpriced. "The steel is worth more than the truck was at the time," he laughs.
Since then, the dilapidated truck has been upcycled into an eye-catching, functional mobile café. Wurtzburg, who conceptualized what is now Sol Coffee, has decades of experience operating cafes in Northern Colorado. "It started off with two premises: that it was going to be a real coffee bar, and that it was going to be off grid," explains Michler. With no generator, the silence surrounding the solar truck is as noticeable as the cacophony of a food truck rally.
Sol Coffee is a full-service food truck serving paninis, espresso drinks, burritos and other offerings. Wurtzburg prefers to use local suppliers. Mark's Coffee, also located in Longmont, provides fair trade, shade-grown coffee. Food and beverage offerings include brands such as Third Street Chai and Boulder Canyon Kettle Chips.
"I believe that a lot of change is done through coffee," states Wurtzburg. "It's a community thing. It's a community bulletin board. . . . What pushed me towards the truck was that I don't like where the cafes are going, with the Internet cafes where everybody is a zombie. They space out on their computers and I don't like it. Initially coffee shops were much more engaging."
Michler and Wurtzburg's shared vision of sustainability prompted a collaboration, with Michler taking the lead on design, visual artist Frank Stanley on fabrication and Wurtzburg on food and beverage operations. They see Sol Coffee more as a gathering place than a transactional place, like food trucks often are.
The creators installed polycarbonate greenhouse wall panels, enclosing the trailer. The lightweight, translucent material lets daylight filter in and illuminates the area surrounding the truck when it operates at night. The center of the floor has been lowered to allow the cook/barista to work more easily.
"We spent a good month figuring out how the whole space is going to work together to make it efficient," says Michler.
Indeed, a lot of work went into ergonomic, aesthetic and functional considerations. The size and configuration of the counters, refrigerator, kitchen equipment, shelves and espresso machine all required much thought. The creators, who hope to replicate the business, believe each iteration will be easier. "We designed the truck around the [photovoltaics]," explains Michler.
The solar panels were ordered before the width of the truck was determined. Energy considerations were included in every step of the process. The trailer currently has three 340-watt solar panels and will soon be adding a fourth. A power bank comprised of two L-16 lead acid batteries provides around two kilowatts of electric storage capacity. Michler and Wurtzburg plan to add two more L-16 batteries very soon. That addition would allow Sol Coffee to operate for about a half day without generating one watt.
Then there's an inverter, which converts solar-generated DC power to AC for use in appliances. A charge controller, located near the energy bank, serves the main purpose of keeping the batteries from being overcharged and "boiling." Michler describes it as an "electron manager," noting, "Off-grid is more about battery management than anything else." Finally, two 30-pound propane tanks power the water heater and espresso machine as needed.
In addition to having a viable, unique business, Michler hopes to catalyze a conversation about what design can accomplish. "This was a design challenge, but we really wanted to have conversations with people about you can do all sorts of things with very low carbon footprint and actually improve the quality of the experience as a result," he says. "So this is just an example of how you can improve people's quality of life, fundamentally, just through design and the way that things operate and [are] built."
Challenges: Adjusting almost daily to the needs of each venue's clients is an operational challenge. Breweries, sporting events, festivals, and private events all come with different demands. "Breweries are certainly food-oriented, less barista-oriented, less drink-oriented," says Wurtzburg. "So those needs have to be swapped out at times. You have to change modes. I have to be a preparatory cook in some ways, at times, and at other times you're a spot-on barista preparing drinks."
The novelty of the business also means that frequent technical tweaks are being made. The optimization process will likely stretch well into the future.
Opportunities: The symbiotic relationship between breweries and food trucks is evident in Colorado's Front Range since few breweries have on-site kitchens. Sol Coffee has a productive, informal partnership with several businesses including Left Hand Brewing Company. When the truck sets up shop at businesses and special events, it's virtually assured there will be positive cash flow.
As the creators see it, the mobile café concept gives them more flexibility than other food trucks. "We can be a morning establishment or an evening establishment," says Michler. Food trucks often draw their entire day's revenue in the few hours surrounding meal times.
The founders are also optimistic that the model will enable them to operate year-round with fewer seasonal fluctuations that other food trucks. When asked where he'd ideally like to be 18 months from now, Wurtzburg says he'd like to have two or three satellites operated by capable managers. "It's novel right now," says Michler. "That's helping us out. But we're really going to have to be dependent on people coming back because they like good coffee and good sandwiches."
Needs: Lithium-ion batteries will eventually replace the current bank, says Michler, though at around $5,000 each they're currently cost-prohibitive. Even without additional trucks at least one more chef/barista with some managerial competencies will also be needed.