Which plug-in solar kit size is right for you?
Last updated
The short answer: pick the size that matches what your home uses while the sun is out. SB 868 doesn't promise to pay you for power you send back to the grid, so size a kit to what you use during the day.[source] And all the plug-in devices at your home together must stay within 1,200 W AC.[source]
The four kinds at a glance
Prices are the range across the kits in our tracker. Savings and payback are on PG&E's standard rate, with typical placement and most of the power used at home, as in our kit tracker. "Not verified" means we don't have a sourced figure yet.
Small kit
Up to 400 W AC
- Price
- $285 to $414
- Saves a year on PG&E
- $73 to $145
- Pays back in
- 2.9 to 3.9 years
A first try, a small balcony, or a home that uses little power during the day.
2 kits we track
See small kits in the trackerStandard kit
401 to 800 W AC
- Price
- $629 to $1,500
- Saves a year on PG&E
- $282 to $290
- Pays back in
- 2.2 to 5.3 years
Most homes that use a steady amount of power during the day.
2 kits we track
See standard kits in the trackerMaximum-size kit
801 to 1,200 W AC
- Price
- $899 to $3,048
- Saves a year on PG&E
- $363 to $451
- Pays back in
- 2.5 to 7.2 years
Homes with high daytime use. It uses most of the per-home limit, leaving little room for another plug-in device.
7 kits we track
See maximum-size kits in the trackerKit with a battery
Any size
- Price
- $1,599
- Saves a year on PG&E
- Not verified
- Pays back in
- Not verified
Homes that use more power after sunset. A battery adds cost.
1 kit we track
See kits with a battery in the tracker
How to choose
- Start with your daytime use. Download a year of usage from your utility account and see how much you use while the sun is out.[source] For a well-placed kit, our calculator expects 800 W of panels to make about 2.4 kWh a day, about 2.2 kWh of it used at home.
- A small kit suits a first try, a small balcony, or a home that uses little power during the day. It costs least, and saves least.
- A standard kit suits most homes that use a steady amount of power during the day: a fridge, a home office, air conditioning.
- A maximum-size kit makes the most power, but only saves more if your home uses it. It takes up most of the per-home limit, leaving little room for another plug-in device.
- A kit with a battery can store midday power for use after sunset.[source] It adds cost, so compare the battery's price with the gap between your evening and midday rates (time-of-use rates explained). It isn't backup power unless the seller shows the complete system keeps working in an outage (batteries and outages).
One kit or two?
The limit is per home, not per kit: the total AC output of all plug-in devices at one home must be 1,200 W AC or less.[source] Be wary of a seller who suggests combining kits to get past it.[source] Our wattage helper adds up what you already have.
Before you buy any size
Check the kit's certification and your outlet, lease and insurance: see before you buy. Then compare kits in the tracker and run your own numbers in the savings calculator.
Not electrical, legal or financial advice.
Frequently asked questions
- Is a bigger plug-in solar kit always better?
- No. Power you send back to the grid probably earns nothing, so a bigger kit only pays off if your home uses its extra power while the sun is out.
- Can I put two kits at my home?
- Only if all the plug-in devices at your home add up to 1,200 W or less. Two kits that each use more than half the limit would be over it together.