The hidden key to solar success: Batteries
Here’s the thing about solar power. When the sun is shining, a solar system instantly converts electrons into electricity. However, what happens on a cloudy day? Or when it rains for days on end? No sun. No electricity. With a variable resource such as solar, the electricity must be used as it is generated or converted immediately into storable forms. That’s a fancy way of saying no solar system is optimal unless is can access a battery system for backup power.
Without a battery to store the energy, a consumer-member’s electric consumption must be matched precisely to those times when solar panels are generating power. That reliable “as needed” model for delivering power – flip a switch and the lights come on – is a cornerstone of electric cooperative service.
Instead of “grid defection” where homeowners rely solely on the energy produced by their solar system, far more people are deciding to install solar panels and batteries while remaining linked to the co-op’s power lines. That way, homeowners can install smaller and cheaper solar power systems while being able to use electricity from the grid as a reliable backup for power.
On their own, the economics of solar power and energy storage are improving steadily. According to the latest Bloomberg New Energy Finance's forecast, the average price of lithium-ion batteries decreased by 80 percent between 2010 and 2018. From 2017 to 2018, the average cost of solar PV panels decreased by 61 percent, according to the Department of Energy's National Renewable Energy Laboratory.