Cheap, Efficient Solar Power: What's Needed Now To Get There?

The report by Baker and colleagues explores the viability of sun-fueled technologies through a combination of evaluations by experts and economic modeling, allowing the researchers to look at solar power’s role in the electricity sector in 15-year chunks through 2095.

Baker has been invited to submit the article to Energy Economics as part of a special issue on Technological Change and Uncertainty in Environmental Economics. It is the first in a series; future reports will assess technologies that harvest wind, biofuels and carbon capture. The U.S. Department of Energy awarded $347,000 to Baker’s team last year to investigate the costs and benefits associated with investing in alternative energies.

Jeffrey Keisler of UMass Boston, and Haewon Chon, a Ph.D. student at the University of Maryland working with the Joint Global Change Research Institute collaborated with Baker.

The scientists approached their analysis of sun-fueled technologies from the framework of a research and development portfolio. They analyzed the risks of certain investments, and solicited advice from experts to identify the key technological breakthroughs in solar technology that would lower its costs. They also asked what hurdles might make it hard to move the technology from the lab to production, and the probability of success, given a funding trajectory. The researchers then fed that information into a model that allowed them to play out various investment scenarios.

The model incorporates information about land use and the energy sector in 14 world regions as well as information on a range of electricity technologies including nuclear power, fossil fuels, biofuels, and solar and wind power. It allows the researchers to look forward in 15-year intervals to 2095, and to ask what’s needed to ensure widespread use of cheap solar power, and how much that would reduce emissions.

“We asked what if technologies that capture solar power were efficient enough to supply the needs of a house through a solar shingle roof,” says Baker. “What breakthroughs would be needed for the solar cells to last the lifetime of the roof, and cost as much or less than fossil fuel-based electricity. And if that technology is to become a reality, what investments are required now.”

Several of their findings bear noting, says Baker. First, even if there are research breakthroughs that made the costs of photovoltaics comparable to or less than that of fossil fuels—roughly 3 cents per kilowatt hour by 2050—there would still be a limited impact on emissions unless the advances are combined with improvements in low-cost storage.

“The development of complimentary technologies, in particular low-cost storage of electricity, is critical,” says Baker. Current technologies do not have good, cheap storage options, and putting all the power into the grid may make it unstable, she says. But when technological breakthroughs are combined with improvements in storage, using solar technology could lower emissions by 20 percent at no additional cost to the economy—taking a serious bite out of the carbon problem.

Baker notes another finding: the experts disagree on how much investment is needed to bring about the breakthroughs required to make solar technology widespread and cheap. But they do agree that federal dollars alone aren’t enough, there has to be more investment from the manufacturing sector.

This suggests that if policy makers want to increase the probability of having the needed technological breakthroughs, they need to encourage investment from the manufacturing sector—this could happen in the form of subsidies, tax breaks or other regulations to increase demand, as well as through support for conferences and public-private collaborations, says Baker.

While the experts disagreed in some areas, they agreed on the order of investment: focus first on getting power from the new inorganic materials that show promise but are far from viable for large scale production. Then focus on purely organic cells with organic semiconductors; these hold the promise of low costs but still haven’t achieved high levels of efficiency and face serious stability problems. And lastly investigate the so-called third-generation cells, which use entirely different technology but may ultimately yield much more power.

Baker acknowledges that the study is preliminary, but she’s pleased that the analytic method, which is commonly applied in industry, can be applied at the public policy level.

“Our analysis should be seen as a tool for informing policy makers on how to balance research and development investments among the various alternative energy technologies,” says Baker. “We hope it takes some of the speculation out of how to craft good climate change policies.”