Utilities increasingly are recognizing the need for grid-level power-storage facilities, including battery banks, as the nation gears up to expand renewable energy. An incident in Texas, in which winds died and grid operators had to cut electricity to industrial customers in order to continue to power homes, underscores the importance of backup facilities for solar and wind power. Technologies that experts are turning to include sodium-sulfur and lithium-ion batteries. "Little attention has been given to massive electricity storage that is a key to making the use of renewable energy possible on a broad scale," according to an American Institute of Chemical Engineers report. "In America today, there is an almost total absence of public awareness of the need."