Scientists are developing flexible, thin-films that will be more resilient and have wider uses than current solar technology.
Now that solar energy is competitive with fossil fuels for making low-cost electricity, has it peaked in the United States?
Nope. We’re probably still looking at only the beginning.
The options for developing new solar businesses are substantial, according to a road map for technology-prone U.S. companies released by the National Renewable Energy Laboratory (NREL).
This is despite the fact that China now dominates solar photovoltaic (PV) manufacturing and may continue its global leadership of the industry for some time.
The new study of rapidly evolving prospects for solar energy suggests there are possibilities for “niche markets” reaching volumes of $1 billion over the next decade. There are a variety of new uses for solar power as it grows still cheaper and more widespread.
The study—“Increasing markets and decreasing package weight for high-specific-power photovoltaics”—was written by solar experts from NREL, a unit of the Department of Energy, and the Colorado School of Mines. It suggests there are lucrative reasons for companies to press ahead with innovative options for solar.
Or, as Matthew Reese, an NREL senior scientist and lead author of the paper, explained, solar electricity has now reached grid parity. That means it can compete with coal and natural gas, formerly the nation’s two most economical sources of electricity.
“One of the things that gets thrown around in the solar community,” he noted in an interview, “is that people didn’t stop making cars when they reached horse parity.”
Solar power was invented in the United States in 1954, when scientists from Bell Laboratories in Murray Hill, N.J., demonstrated a new invention. It was a panel made of silicon that produced enough electricity under the stimulation of the light of a small sun lamp to turn a toy Ferris wheel (Climatewire, Dec. 16, 2016).
In recent years, China has used subsidies and innovations on silicon-based PV to create a scale that will make it “remarkably hard” for competitors to match, Reese explained. But there are new thin-film technologies for making solar electricity, he noted, that are just beginning their growth curves. They hold the potential for disrupting old markets and creating new ones.
Silicon has historically enjoyed lots of subsidies compared with thin-film PV, Reese said, pointing out that the original development of silicon PV was financed by billions of dollars from the semiconductor industry, whose main objective was making the modern computer. Solar power was a secondary challenge, but it has eventually matured to the point where panels can be ensured to produce 30 years of reliable electricity.
The U.S. Office of Naval Research is sponsoring NREL’s newest research into other compounds that can be made into thin films capable of generating electricity from light. Lighter and more flexible than silicon, they include cadmium telluride, copper indium gallium selenium and a family of related rocks called perovskite (Climatewire, April 24, 2017).
The challenge from the Navy was “can you make really lightweight solar, the lightest weight possible,” and find the material whose use could be scaled up at the lowest cost, recalled Reese.
Basically, the Navy and other U.S. military units are looking to solar-generated electricity as a way to eliminate batteries—and reduce casualties.
The military learned in Iraq, and later in Afghanistan, that soldiers in forward-positioned units sometimes have to carry 80 to 100 pounds of gear. A substantial portion consists of batteries for a variety of equipment.
That’s just the beginning of an array of logistical problems. The batteries had to be recharged by diesel-powered generators that in turn required expensive flights or truck convoys to deliver more fuel. Those convoys were frequently attacked.
The new study asserts that although emerging lightweight and flexible thin-film solar technologies may be more expensive to make than conventional silicon, their lighter weight and greater resilience will fetch higher prices, improve logistics and, in the Navy’s case, save lives.
Lighter-weight materials and packaging may eventually pay for itself in rooftop solar by reducing installation costs on houses, but they will likely penetrate other solar markets more quickly.
The scientists foresee more solar uses in buildings, where lightweight solar materials can be introduced on windows, in shingles and on other architectural features. Growing demand will reduce their costs, while the recent development of flexible and scratch-proof glass may extend their market reach.
The NREL report notes widening uses for lightweight and more compact solar power in small space satellites called “cubesats” that are now proliferating. Reese noted that electric vehicles such as the Toyota Prius come with a solar-powered option and a small fan that blows accumulated heat out of parked cars, a step that saves electricity and thus extends the range of EVs.
Another opening for more efficient and smaller solar units discussed in the study is “indoor light harvesting,” or generating power from a mix of interior lighting. Such an option may work in office buildings that have both outdoor light and overhead fluorescent tubes. There, small solar-powered devices could turn the light back into electricity to power electronic devices or an array of sensors that would not need to be close to an electric outlet.
Reese noted that further uses for small solar-powered units will come in the development of drones and other unmanned aerial vehicles, such as balloons that were used last year in storm-crippled Puerto Rico to quickly restore internet service for email and texting.
The steerable balloons, developed by Alphabet Inc., Google’s parent company, were called “experimental technology.” In the future, though, similar vehicles could be useful to help cities and states recover from power outages.
As one expert put it, “Think of each balloon as a cell tower in the stratosphere.”
For Reese, the continuing evolution of cheaper and more omnipresent solar power will lead to its application to technologies that haven’t been economical before. One such example: desalination plants in the drought-plagued western United States.
“Similarly,” he noted, “if you worry about things like accumulating CO2 in the atmosphere, if your energy was cheap enough there may be a more energy-intensive process such as sucking CO2 out of the air and solidifying it.”