Feature Editor: Paulina Jaramillo
(Article in Energy Quarterly (EQ) in the March 2011 issue of MRS Bulletin)
On August 14, 2003, a downed high-voltage power line in Ohio triggered a massive blackout across eight states in the Northeast and throughout Southeastern Canada. A total of 50 million people lost power for up to two days. The episode cost an estimated $6 billion and is considered to be the worst electrical system failure in the history of the United States.
The cascade of failures—due to both human error and equipment malfunction—made clear the problems of the United States’ aging and balkanized electrical transmission grid. The blackout spurred the U.S. Congress to pass the Energy Policy Act of 2005, which enforces mandatory reliability standards. Investment in the transmission grid had fallen during the 1980s and 1990s, but after the blackout, funding picked up again.
Against this backdrop, power companies and regulating authorities now have another challenge to face: how to integrate variable and intermittent renewable resources such as solar and wind into the mix. Currently, electricity from non-hydro renewable resources accounts for 3.8% of the total electricity produced in the United States, according to the U.S. Energy Information Administration. In 2009, half of non-hydro renewable electricity came from wind and less than one percent from solar.
Although wind and solar are attractive because they do not produce greenhouse gases, they also pose difficulties because of their inherent variability. If wind and solar must supply a third of the energy generated, the job of meeting changing demand for electricity throughout the day becomes much more difficult. Power plant operators must meet the net load—the difference between user demand and this highly variable renewable output—by scheduling power generation from conventional sources.
An Energy Sector Analysis article published in the Energy Quarterly section in the March 2011 issue of MRS Bulletin discusses various options to manage net load variability in the electric grid, with a focus on energy storage technologies. For materials scientists, a lot of potential research for grid-level energy storage lies in developing advanced battery technologies. Superconducting magnetic energy storage (SMES) systems are another option and have been used since the 1970s, mostly to release short bursts of energy to smooth out fluctuations in the power supply.
Gopal R. Rao
Editor, MRS Bulletin
Materials Research Society (MRS)