One of the biggest myths about renewable energy is that it isn’t reliable. Sure, the sun sets every night and winds calm down, putting solar panels and turbines to sleep. But when those renewables are humming, they’re providing the grid with electricity and charging banks of batteries, which then supply power at night.
A new study in the journal Renewable Energy that looked at California’s deployment of renewable power highlights just how reliable the future of energy might be. It found that last year, from late winter to early summer, renewables fulfilled 100 percent of the state’s electricity demand for up to 10 hours on 98 of 116 days, a record for California. Not only were there no blackouts during that time, thanks in part to backup battery power, but at their peak the renewables provided up to 162 percent of the grid’s needs — adding extra electricity California could export to neighboring states or use to fill batteries.
Just as people can get sunburns in overcast skies, solar still works as a net positive energy collection system when scaled correctly. This is why locations with more frequent inclement weather tend to have larger battery stores because even if you only get 0.5kwh from an overcast day, you’re still offsetting that much power use from the grid and over time, it adds up, while the good days help offset the bad days in terms of energy collection so long as you have the storage capabilities.
The primary problem with almost all power systems is how to reliably store as much of that energy as possible given a variable rate of load.