Solar power holds the most growth potential of all renewable energy technologies and is the lowest-cost option for mitigating the risk of irreversible climate change says a major new report from the Massachusetts Institute of Technology Energy Initiative (MITEI).
Focused predominantly on the U.S. sector, “The Future of Solar Energy” (PDF), study examines the state of currently available solar technologies, deployment of solar power systems, regulatory frameworks affecting the rollout of solar and federal subsidy arrangements which benefit the market. It then recommends changes to industry leaders and policymakers that would lead to stronger long-term growth.
“Our objective has been to assess solar energy’s current and potential competitive position and to identify changes in US government policies that could more efficiently and effectively support its massive deployment over the long-term, which we view as necessary,” said Robert Armstrong, Director, MITEI.
One of these changes is to cut funding for research and development into conventional crystalline silicon (c-Si) solar wafer technology. By reducing the use of silver in manufacturing, it increases the potential to expand to terawatt levels. The report recommends increasing spending on thin-film PV research which it says has far more potential for growth per dollar spent, but only if the technology uses Earth-abundant elements (unlike commercial CdTe thin-film cells, made from telluride, an element four times rarer than gold).
As energy storage solutions become more advanced, concentrated solar power (CSP) technologies also become more cost efficient. Spending on R&D would be best spent on better system designs that operate at far higher temperatures. The report recommends a move away from the U.S. government’s federal loans guarantee model for CSP projects to a funding scheme based on the chemical industry, which could build affordable high-risk pilot-plants, encouraging innovation without scaring off investors.
Residential solar energy such as rooftop solar power was found to cost up to 80 per cent more per customer than electricity sourced from utility-scale plants, mainly due to balance-of-system (BOS) costs – the price of solar panels, racking, inverters and installation. However, with these costs competitive across all states, the study concluded that a national effort to streamline rules and procedures for permitting, interconnection, and inspection (PII) could help lower the installed system costs in the residential sector.
Allowing more third-party ownership of rooftop PV systems also increase deployment of solar power. Currently half the states in the U.S. do not allow homeowners access to residential solar leasing schemes, which the report found has rapidly expanding the uptake of solar energy across America. Relaxing these rules would be a boon for the industry and the environment, according to the report.
Finally, the report recommends a putting a price on carbon to bring the levelised cost of energy (LCOE) from solar power into line with that of fossil fuels, along with a mandated national Renewable Portfolio Standard that would replace current state-based models, allowing eligible solar generators to be sited anywhere, regardless of state or region.
