Industrial facilities will be among the most difficult emitters to decarbonize.
The industrial sector — everything from factories to food producers to oil refiners — accounts for one-third of U.S. primary energy demand, according to the Department of Energy. At many of these facilities, fossil fuels, and especially natural gas, are the energy feedstock used for process heating applications.
But what if the sun’s energy could take over the job much of the time and displace fossil fuels?
Dallas-based startup Skyven Technologies recently completed the first installation of its Intelligent Mirror Array (IMA). The system, deployed at Copses Farms, a state-of-the-art robotic dairy farm in Valley Falls, New York, uses solar thermal collectors to raise the temperature of water used to sanitize the facility’s self-cleaning milking robots.
The IMA systems installed at Copses Farms will supply enough heat to produce 50,000 gallons of hot water each year. The solar thermal collectors supply heat previously provided by burning propane and wood, according to Skyven’s founder and CEO Arun Gupta.
Skyven Technologies was the $1 million grand-prize winner of the 2017 76West Clean Energy Competition. The annual competition, administered by the New York State Energy Research and Development Authority, offers $20 million in prize money and support services to boost the clean energy economy in New York’s Southern Tier region. Skyven also received a $750,000 grant from the National Science Foundation’s Small Business Innovation Research program.
The segment targeted by Skyven Technologies — industrial process heat — is ripe for a clean energy transition. Together, these applications account for roughly 25 percent of U.S. industrial sector primary energy consumption.
Solar thermal in a PV form factor
Skyven’s IMA is a flat panel box similar in size and weight to a 300-watt solar PV module. But rather than containing photovoltaic cells, the collector holds an array of mirrors, which track the sun throughout the day.
“We’ve taken concentrating solar technology and fit it into a PV form factor,” Arun Gupta told Greentech Media. “The PV form factor has been proven time and time again to be economically attractive in behind-the-meter C&I applications. And so, we’re piggybacking on PV form factor installation techniques.”
Each IMA collector, roof-mounted in rows at 45 degrees, is paired with its own linear receiver. Sunlight from the mirrors is focused on a black pipe in the receiver through which water or glycol flows in a loop to and from a heat exchanger located inside the industrial facility.
Heat from the IMA collector, which hits temperatures as high as 400° Fahrenheit (204°C), can be used for a variety of industrial process heating applications ranging from feeding heat to existing boilers to preheating dryer intake air or preheating water for clean-in-place sanitation systems like the one used at Copses Farms.
According to researchers at the National Renewable Energy Laboratory, slightly more than 50 percent of industrial process heating demand requires temperatures below 300°C (572°F). Concentrating solar technologies like the IMA system could therefore provide heat for many of these use cases such as the production of food, milk and beer.
America’s craft beer industry, to cite one example, could be an ideal market to turn to solar thermal technology in place of natural gas. As of 2018, nearly 85 percent of the Btu consumed by the U.S. beverage sector for boiler and process heat came from natural gas.
Temperatures of brewing processes such as mashing (70°C/158°F) and boiling (100°C/212°F) are well within the range of heat provided by Skyven’s IMA system.
Cheaper than natural gas
Skyven aims to fill a specific marketplace need, Gupta said. Existing distributed solar thermal technologies are proven and have been around for a long time, but “they also don’t get hot enough for use in the industrial sector.”
“They’re fine for pool heating, for a hot shower. But they’re certainly not going to do things like pasteurize milk or cook bread.”
Meanwhile, he noted, other solar thermal technologies — parabolic troughs, parabolic dishes, Fresnel reflectors — were developed for use at utility-scale power plants.
“They’re not well suited for behind-the-meter, on-site industrial applications,” Gupta said. “We developed our solar concentrator in order to produce higher-temperature heat that is directly usable by these food production and industrial plants.”
Skyven Technologies makes money on the heat delivered to customers.
The company’s standard approach, said Gupta, is to “bill for Btu that are measured and actually delivered to the plant, and bill at a lower rate than the customer was paying for delivered fuel.”
Here, he added, “the customer has no cost outflow other than for real Btu that they would have had to buy anyway, at a higher price. Every Btu our systems produce is one Btu of fuel that they don’t have to burn.”
Gupta claims Skyven is able “to beat the delivered cost of natural gas by 10 to 50 percent, depending on the specifics of the project.”
Customers sign a long-term, multiyear heat supply agreement with Skyven that includes maintenance of the equipment.
Skyven’s customers can opt for a no- or partial-capital outlay installation. Gupta likened the no-money-down option to a C&I customer signing a power-purchase agreement for a rooftop solar PV installation.
In this case, Skyven owns, operates and maintains the system and retains any available state and federal incentives. For instance, Gupta said Skyven’s technology is eligible for both the federal solar Investment Tax Credit and rebates under California’s CSI-Thermal Program.
Customers can also opt to buy Skyven’s equipment outright.
Next up: California’s Central Valley
Up next for Skyven Technologies is the installation of IMA collectors at three food processing facilities in California’s Central Valley.
With support from the California Energy Commission’s Food Production Investment Program, in 2021 Skyven will install the same IMA technology deployed at New York’s Copses Farms at dairies operated by California Dairies, Inc., in Visalia, and Land O’Lakes, Inc., in Tulare, and a tomato processing facility operated by Olam West Coast, Inc. in Lemoore.
In a research note, CEC staff provided justification for the commission’s investment in the projects.
“There is a lack of successful, high-temperature demonstrations of solar thermal energy systems in dairy processing facilities. Supplementing heat required for thermal processes with solar thermal energy could significantly reduce natural gas consumption and GHG emissions in dairy processing industries,” they wrote.
The three projects will receive a total of $9.42 million in funding from the Food Production Investment Program grant program and are scheduled to come online by late 2021 or early 2022.