A U.K. homeowner wanted more from their solar panel and battery system because it wasn't providing enough energy on cloudy days to get past lunchtime. 

Here's what to know

In a Reddit post, they described a system purchased through an energy provider that includes two 5-kilowatt-hour batteries and 10 400-watt solar panels. The installation cost just over £13,000 ($17,500).

Overnight charging on the Octopus Go tariff supplies the homeowner's 10 kWh of battery storage. 

Rather than expand the existing system, the homeowner began looking for less expensive ways to power individual appliances. Additional 5-kWh batteries would cost £4,000 to £5,000 ($5,400 to $6,700) each, they said.

Upfront cost aside, adding battery storage can save money on energy, provide more energy independence, and protect your home during outages.

For homeowners comparing those capabilities and costs, EnergySage offers information about home battery storage options, including competitive installation estimates. EnergySage has teamed up with electrification brand Qmerit to help homeowners get the best price on home battery storage solutions.

More background

Under the homeowner's proposal in the Reddit post, instead of enlarging the existing system, they would buy three Anker S2000 portable batteries. A home computer lab, fish tank, and refrigerator would each get a dedicated power supply.

Professional installation would not be necessary for the portable units. By the homeowner's calculation, they would cost less than half as much as one additional battery for the existing system while supplying 6 kWh of storage.

Another Redditor had already begun taking a similar approach, writing, "I just bought my second S2000 on the way to buying a third, so your approach has at least one other adherent."

One commenter saw two potential uses for the S2000: storing electricity during cheaper hours and backing up essential appliances. How long the savings would take to cover the purchase price remained a concern.

That commenter estimated a 10-year payback period for a standard refrigerator, based on the electricity savings needed to recover the battery's purchase price.

What can be done?

One commenter explained that isolating a home's batteries from the grid during an outage protects repair crews from electricity fed back onto power lines. In professionally installed systems, a gateway can disconnect the home from the grid.

For portable batteries, the intended connection is between the unit's own outlet and an appliance, not the household wiring.

Pila offers another strong battery backup option; its plug-and-play batteries cost a fraction of a whole-home backup system.

Where can I learn more?

Solar panels and batteries can provide power during an outage or enough stored energy to last the day, but the setup matters. 

• A U.K. homeowner learned blackout backup costs extra after buying solar and battery storage.

• A homeowner's solar stopped working during outages despite battery backup.

• U.K. owners say 5-kWh batteries need grid top-ups most winter nights when solar generation drops.

• One U.K. homeowner nearly filled a 16-kWh battery on a cloudy day, questioning smaller systems.

• A U.K. homeowner's $30,000 solar quote sparked debate over more panels versus winter battery storage.

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