The batteries’ unique design could smooth out the power from renewables and help usher in the rise of more resilient microgrids
THE future of energy storage has taken root on an onion farm in southern California.
Seeking to offset its electricity bills, Gills Onions in Oxnard has installed a flow battery. When electricity prices from the grid peak, the farm can tap stores of energy created by processing agricultural waste. The battery can supply 600 kilowatts of electricity over six hours to run farm machinery for a fraction of the usual cost.
Flow batteries are centred around two aqueous electrolytes, which are held in separate tanks when the battery is idle. To get electricity from it, the liquids are pumped into a chamber separated by a membrane, sparking an electron-producing chemical reaction across the membrane. To store energy, an external current is applied across the membrane and the process works in reverse.
The batteries’ size – they can be as big as shipping containers – and ability to store large amounts of energy make them well suited to smoothing out the variable supply of wind, solar and other renewable energies. But they are expensive, and their pumps and tubes make them difficult to maintain.
Several firms are now coming to market with designs that they say address those concerns, opening the door to the possibility that battery backups for renewables could one day form a constellation of self-sufficient microgrids far more resilient than the present electrical infrastructure.
Read more at: NewScientist.com