Question 1

What size solar battery do I need for my home?

Accepted Answer

Most homes need a battery between 4 kWh and 15 kWh. A 4-8 kWh battery covers essentials (lights, fridge, WiFi, security) for 4-6 hours of backup. An 8-15 kWh system can power your whole home including air conditioning. Use our calculator above to get a personalized recommendation based on your actual monthly usage and backup needs.

Question 2

How long do solar batteries last?

Accepted Answer

Solar battery lifespan is measured two ways. Calendar life is the expected service life regardless of use — most lithium-ion batteries last 8-12 years before their internal chemistry degrades. Cycle life is how many charge-discharge cycles the battery can handle before capacity drops below 80% — typically 3,000-6,000 cycles depending on depth of discharge (DoD). The lower you regularly discharge the battery (e.g., 20% DoD vs 80% DoD), the more cycles it will last. In practice, the calendar life usually comes first: a daily cycled battery rated for 5,000 cycles could theoretically last ~13 years, but its calendar life might limit it to 10.

Question 3

Do solar batteries work during a power outage?

Accepted Answer

Yes, solar batteries can power your home during a blackout, but with one important caveat: most grid-tied solar systems shut off during an outage for safety unless paired with a battery. A properly configured solar + battery system automatically disconnects from the grid and runs your essential loads from battery power.

Question 4

What's the difference between kW and kWh? Why does it matter?

Accepted Answer

Think of it like a water tank. kW (kilowatt) is the size of the pipe — how much power can flow at once to run your appliances. kWh (kilowatt-hour) is the size of the tank — how much energy can be stored. Your battery capacity is measured in kWh (how long it lasts), while your inverter size is measured in kW (how many appliances you can run simultaneously). For example, a 10 kWh battery paired with a 5 kW inverter can run up to 5 kW of appliances at the same time for about 2 hours. If you undersize the inverter (kW), you won't be able to run your oven and AC together; if you undersize the battery (kWh), it will drain too quickly.

Question 5

How much money can I save with a solar battery?

Accepted Answer

Savings depend on your local electricity rates, solar irradiance, and system size. Typical savings range from 30-70% on monthly electricity bills. Homes in areas with high electricity costs ($0.25+/kWh) and good net metering policies see the fastest payback, often 4-8 years. Our calculator estimates annual and monthly savings for your specific country and usage.

Question 6

Can I go off-grid with solar batteries?

Accepted Answer

While technically possible, going fully off-grid requires a much larger battery bank and solar array — typically 2-3× the size of a grid-tied backup system. Most homeowners choose grid-tied systems with battery backup, which gives you the reliability of the grid plus backup power during outages, at a fraction of the cost of going fully off-grid.

Question 7

Solar battery vs generator — which is better?

Accepted Answer

Solar batteries are quieter, cleaner, and cheaper to operate long-term than generators. Generators have lower upfront costs ($500-2,000) but require ongoing fuel and maintenance. Solar batteries cost more upfront ($1,100-3,900) but have zero fuel costs and last 8-12 years. For frequent or long-duration power needs, solar + battery is more cost-effective over time.

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