(Bloomberg) — Californians have embraced rooftop solar panels more than anyone in the U.S., but many are learning the hard way the systems won’t keep the lights on during blackouts.
That’s because most panels are designed to supply power to the grid — not directly to houses. During the heat of the day, solar systems can crank out more juice than a home can handle. Conversely, they don’t produce power at all at night. So systems are tied into the grid, and the vast majority aren’t working this week as PG&E Corp. cuts power to much of Northern California to prevent wildfires.
Hilarious! The long explanation is that Solar Panels produce low voltage DC, that is passed through an Inverter changing it to AC current. Which is connected to the power wires coming from (and going back to the outside pole) the power utility.
To keep the power that is coming from the roof panels for use at home you would need to store the power inside your own house. The most common and easiest way is with batteries. Batteries are not cheap, and enough battery storage to get you through even one day of no power from the utility is going to take up a bit of space. That space will need to be in the garage (if you have one) or in the basement; because batteries are also very heavy (and expensive, did I mention expensive?). BTW, I’d think twice before I’d invest in Lithium cycle batteries for this purpose! At least inside the house, a Lithium battery that overheats can catch fire and is exceedingly hard to extinguish.
So then you need another (expensive) device to regulate the DC power being sent to the battery; charging the batteries to their capacity and then sending the excess power to the grid through the Inverter (still need that!).
During a power outage, you are going to want to draw on the power stored in the batteries, right? Unless you invest in 12volt DC appliances and lightning, you are going to need another DC to AC inverter. My, my! The cost of all this stuff is really starting to add up.
Might as well start saving up for when the time comes to replace all that expensive equipment, including the Solar Panels on the roof (15-20 years). The inverters (20-25 years). The batteries (5-10 years). However the system won’t last that long unless you budget in regular maintenance by a certified electrician ($150/ hour).
Of course you could just get a gasoline/LP/Natural Gas/diesel emergency generator, sitting outside ready to kick in automatically as soon as the power goes out; that’s what I’d do. Be a lot cheaper and much more reliable and long lasting. But then that’s all EVIL fossil fuels, so you couldn’t do that!