Deploying different energy storage technologies can optimize the use of increasing but intermittent renewable energy sources and enable the United States to fully shift off fossil-fuelled generation systems by mid-century, a Massachusetts Institute of Technology Energy Initiative (MITEI) study concludes.
Excess solar and wind energy output can be stored and feed the grid at times of high demand, “maintaining reliability in a cost-effective manner—that in turn can support the electrification of many end-use activities beyond the electricity sector,” said MITEI Director Robert Armstrong.
The 400-page study was developed by MITEI over three years before its release last month. It analyzes various strategies for using existing and emerging electrochemical, thermal, chemical, and mechanical storage technologies to capture variable wind and solar energy flows and ultimately decarbonize the U.S. grid by 2050, reports Utility Dive.
The study calls for changes in U.S. grid planning and operational tools to better reflect the transition needed to fight climate change, the news story states. It also recommends changing the U.S. government’s habit of granting intellectual property rights to private sector partners in exchange for sharing project costs, a practice that compromises the “basic objective” of publicly-funded demonstration projects.
That finding leads into a call for more public investments in technology demonstrations and early deployments to disseminate knowledge, Utility Dive says. As well, policies in the U.S. and beyond “must be adjusted to avoid excess and inequitable burdens on consumers, to encourage electrification for economy-wide decarbonization, and to enable robust economic growth, particularly in emerging market developing economy countries” as storage technologies scale up.
The study looks at cost-effective pathways to decarbonize U.S. electricity systems and reduce emissions 97 to 99% below 2005 levels, based on assumptions about the declining cost of wind and solar technologies. “Modeling shows that decarbonized systems in which wind and solar generation play a dominant role will have zero or low marginal system costs of energy during many hours,” in contrast to dispatchable generation using fossil fuels, said MIT senior energy economist Howard Gruenspecht.
MITEI calls for more research and support for longer-duration storage technology, and higher fixed charges for energy storage to ensure the technologies reap a profit, Utility Dive writes.
Because of the high capital and low variable costs of future decarbonized systems, “fixed charges should play a larger role in cost recovery than they do presently,” including basing charges on consumers’ income level “to address equity as well as efficiency,” Gruenspecht said.