Solar energy has big potential but needs technology and deployment changes to be sustainable

Cambridge, Mass. -- Solar energy holds the best potential for meeting humanity’s future long-term energy needs while cutting greenhouse gas emissions — but to realize this potential will require increased emphasis on developing lower-cost technologies and more effective deployment policy, says a comprehensive new study, titled “The Future of Solar Energy,” released by the MIT Energy Initiative (MITEI).

“Our objective has been to assess solar energy’s current and potential competitive position and to identify changes in U.S. government policies that could more efficiently and effectively support its massive deployment over the long term, which we view as necessary,” says MITEI Director Robert Armstrong, the Chevron Professor in Chemical Engineering at MIT.

The study’s chair, Richard Schmalensee, the Howard W. Johnson Professor Emeritus of Economics and Management at the MIT Sloan School of Management, adds, “What the study shows is that our focus needs to shift toward new technologies and policies that have the potential to make solar a compelling economic option.” The study group is presenting its findings to lawmakers and senior administration officials this week in Washington.

“The Future of Solar Energy” reflects on the technical, commercial, and policy dimensions of solar energy today and makes recommendations to policymakers regarding more effective federal and state support for research and development, technology demonstration, and solar deployment.

Among its major themes is the need to prepare our electricity systems, both technically and from a regulatory standpoint, for very large-scale deployment of solar generation — which tends to vary unpredictably throughout the day. To this end, the study emphasizes the need for federal research and development support to advance low-cost, large-scale electricity storage technologies.

The analysis finds that today’s federal and state subsidy programs designed to encourage investment in solar systems should be reconsidered, to increase their cost-effectiveness, with greater emphasis on rewarding production of solar energy. The group also recommends that state renewable portfolio standards, which are designed to increase generation of electricity from renewable resources, be brought under a unified national program that would reduce the cost of meeting set mandates by allowing unrestricted interstate trading of credits.

Surprising Findings?

The report has some surprising findings, such as the fact that thin-film solar PV is a more environmentally-friendly technology and should be pursued at a greater level than crystalline silicon technology.  Another finding that may surprise some is that distributed generation, when deployed at a large number of sites, strains the grid, increasing distribution costs (and rates) because new investments are required in order to accommodate the two-way flow of electrons.  Further, the report says that net-metering, the method that allows PV system owners to sell the electricity they produce back to the utility at a retail rate, is unsustainable and should be changed:

Because of these conflicts, robust, long-term growth in distributed solar generation likely will require the development of pricing systems that are widely viewed as fair and that lead to efficient network investment. Therefore, research is needed to design pricing systems that more effectively allocate network costs to the entities that cause them.

The authors posit that large-scale centralized solar PV could be a better way to meet the world's energy challenges without putting an unfair burden on some. The potential of solar is huge, say the researchers, but many changes are still needed to bring the technology to its full potential. The authors conclude the exectutive summary this way:

Nevertheless, while costs have declined substantially in recent years and market penetration has grown, major scale-up in the decades ahead will depend on the solar industry’s ability to overcome several major hurdles with respect to cost, the availability of technology and materials to support very large-scale expansion, and successful integration at large scale into existing electric systems.

http://www.renewableenergyworld.com/rea/news/article/2015/05/affordable-solar-energy-has-big-potential-says-mit