How to Store Solar Energy Without Batteries: 5 Options

You can store solar energy without batteries in five practical ways: net metering, heating water, pre-cooling or pre-heating your home, shifting appliance use to sunny hours, and charging an electric car. Together they can soak up 20 kWh or more of midday solar a day, often for under $300.

First, a quick reminder: solar panels themselves store nothing. If you want the basics on panels, batteries and net metering, start with can you store solar energy? This article goes deep on the battery-free options only.

None of these methods give you power during a blackout. For that, you still need a battery or generator. But they can capture much of the value a battery would, for a small fraction of the roughly $15,600 a 13.5 kWh battery costs installed (EnergySage, 2026).

1. Can net metering store solar energy for you?

In effect, yes. With net metering, your extra daytime power flows to the grid and your utility credits your account. At night, you draw power and use the credit. The grid acts like a giant battery you don’t have to buy.

How good a deal this is depends on your export rate:

• Full retail net metering: 1 kWh exported = 1 kWh credited. At the 2026 US average of 18.2¢/kWh (EIA), 10 kWh a day × 365 × $0.182 = about $664 a year of credit.
• Net billing at 5¢: 10 kWh × 365 × $0.05 = about $183 a year. The same power is worth far less.

California’s NEM 3.0 is the best-known net billing plan. Under it, using your own solar is usually worth much more than exporting it. That is why the other four options matter so much there. See solar panels in California for local details. To check your own state’s rules, search DSIRE (linked below).

2. Can you store solar energy as hot water?

Yes, and it is one of the best-kept secrets in home solar. An electric water heater is already a big insulated tank. If you heat it with midday solar, the hot water is ready for evening showers.

Here is how much energy a 50-gallon tank holds:

• 50 gallons × 8.34 lb per gallon = 417 lb of water
• Heating it 60°F (from 60°F to 120°F): 417 lb × 60°F = 25,020 BTU
• 25,020 BTU ÷ 3,412 BTU per kWh = about 7.3 kWh

That is more than half of a 13.5 kWh battery, stored in an appliance you already own.

How to do it:

• A simple timer (about $50–$150 for a 240V water heater timer) lets the heater run only from roughly 10 a.m. to 4 p.m.
• A heat pump water heater uses about a third of the power of a standard electric unit, and many have schedule or “grid-connected” modes. The DOE explains how they work in the source below.
• A solar diverter sends only your surplus solar to the heating element. These are common in some countries and less so in the US, so check that any unit is UL listed.

A heat pump water heater stores the same 7.3 kWh of heat using only about 2–3 kWh of electricity. That makes it even more useful for small solar systems.

Safety note: water heaters run on 240V circuits. Have a licensed electrician install any timer, diverter or new heater. The work must follow the National Electrical Code (NEC) and local permit rules.

3. Can you store solar energy by pre-cooling or pre-heating your home?

Yes. Your house has thermal mass: walls, floors, furniture and air. If you cool it a few degrees below normal in the afternoon, it stays comfortable longer after sunset. The AC runs less in the evening, when solar output is gone and rates are often highest.

Example with a typical 3-ton central AC drawing about 3.5 kW:

• Run it 2 extra hours from 2 to 4 p.m.: 3.5 kW × 2 hours = 7 kWh of solar used
• If that saves 2 hours of evening run time, you avoid 7 kWh of grid power
• 7 kWh × $0.182 = about $1.27 a day, or about $115 over a 90-day summer

Real savings vary with insulation, weather and how warm you let it get. A smart thermostat (about $100–$250) makes this automatic. In winter, the same trick works with a heat pump: warm the house in the early afternoon. For sizing panels to run AC, see solar powered air conditioner.

4. How does load shifting save solar energy?

Load shifting means moving flexible chores into sunny hours. You are not storing energy. You are using it before it would be exported at a low rate.

One dryer load, one dishwasher load and a pool pump schedule can add up to 8–10 kWh a day. Pool owners should see how many solar panels to run a pool pump.

5. Can an electric car store your solar energy?

Yes. An EV battery is often five times larger than a home battery. Charging it at midday turns surplus solar into miles.

• 40 miles a day × about 0.3 kWh per mile = 12 kWh a day
• 12 kWh × 365 = 4,380 kWh a year that could come from your roof

The catch: the car must be home during the day. This works best for remote workers, retirees or second cars. Some EVs and chargers also support vehicle-to-home (V2H) backup, but it needs special equipment and a licensed electrician.

Why don’t pumped water and gravity storage work for homes?

Pumped hydro is the largest form of grid storage in the US. Utilities pump water uphill into huge reservoirs. At home scale, though, the numbers are tiny.

Pumped water example: lift 1,000 gallons (about 8,340 lb, or 3,785 kg) up 30 ft (9.14 m).

• Energy = mass × gravity × height = 3,785 × 9.81 × 9.14 = about 339,000 joules
• 339,000 ÷ 3,600,000 joules per kWh = about 0.09 kWh
• After pump and turbine losses, you might get back 0.07 kWh, worth about 1¢

Gravity example: lift a 1,000 lb (454 kg) weight 10 ft (3.05 m). 454 × 9.81 × 3.05 = about 13,600 joules, or 0.004 kWh. You would need to lift it about 2,500 times to store 10 kWh.

Compare that with the water heater: 7.3 kWh in a tank you already own. Heat stores energy far more densely than height does at home scale.

Which battery-free option should you start with?

If you have full net metering, you may not need any of this. If your exports earn little, start with free load shifting, then the water heater. If you also want blackout backup, compare solar batteries. And if you’re wondering what powers your home after dark, read do solar panels work at night?

Frequently asked questions

Can I use solar without batteries during a power outage?

Usually not. Standard grid-tied inverters shut off when the grid fails, to protect line workers. A few inverters offer a small daytime-only outlet, but whole-home backup needs a battery or generator.

Is a water heater really a solar battery?

Not for electricity. It stores heat, which you can only use as hot water. But since water heating is a big share of many home bills, that heat is very useful.

Can I store solar energy in ice?

Some commercial buildings make ice during the day to cool at night. Home-sized ice storage systems are rare and costly in the US, so pre-cooling is the practical version.

What happens to extra solar if I don’t store or export it?

The inverter cuts back output, and that energy is simply not produced. This is called curtailment.

Sources

• US Department of Energy: Heat Pump Water Heaters
• US Department of Energy: Pumped Storage Hydropower
• DSIRE: State net metering and incentive programs

Last updated: October 2026. Appliance figures and savings are estimates; your results will vary. This article is for information only and is not electrical advice.