On-Grid vs Off-Grid vs Hybrid Solar Calculator
On-grid, off-grid, or hybrid solar: which suits your home? Compare all three side by side for the same electricity use or the same equipment, with their size, usable generation, upfront cost, 25-year cost, and backup in a power cut.
Three ways to power your home
Near Los Angeles, On-grid has the lowest 25-year cost on these numbers, at about $23,800. Staying on the grid alone would cost about $32,400.
| Item | On-grid | Hybrid | Off-grid |
|---|---|---|---|
| Solar size | 3.9 kW | 3.9 kW | 6.7 kW |
| Battery | None | 13.5 kWh | 33 kWh |
| Solar generated | 7,200 kWh | 7,200 kWh | 12,282 kWh |
| Solar used at home | 2,720 kWh | 6,510 kWh | 7,200 kWh |
| Sent to the grid | 4,480 kWh | 268 kWh | 0 kWh |
| Solar wasted | 0 kWh | 0 kWh | 4,602 kWh |
| Use not covered | 0 kWh | 0 kWh | 0 kWh |
| Home use from solar | 38% | 90% | 100% |
| Upfront cost | $10,300 | $23,400 | $51,600 |
| Yearly bill after | $448 | $103 | $0 |
| Yearly saving | $848 | $1,200 | $1,300 |
| Simple payback | 12.1 years | 19.6 years | 39.8 years |
| 25-year cost | $23,800 | $42,200 | $89,900 |
| Power in an outage | No | Yes | Yes |
Assumptions used
- Bill today
- $1,300 a year
- Battery replaced
- Once, around year 12
- Off-grid sizing
- Darkest month, plus a 25% margin
- Prices
- Held flat for 25 years
Follow a typical day
Panels, a battery, and the grid. It can keep running in a power cut.
| Point | Solar output | Home use |
|---|---|---|
| 00:00 | 0 | 0.91 |
| 01:00 | 0 | 0.91 |
| 02:00 | 0 | 0.91 |
| 03:00 | 0 | 0.91 |
| 04:00 | 0 | 0.91 |
| 05:00 | 0 | 0.91 |
| 06:00 | 0 | 0.91 |
| 07:00 | 0.48 | 0.72 |
| 08:00 | 1.1 | 0.72 |
| 09:00 | 1.7 | 0.72 |
| 10:00 | 2.16 | 0.72 |
| 11:00 | 2.4 | 0.72 |
| 12:00 | 2.39 | 0.72 |
| 13:00 | 2.14 | 0.72 |
| 14:00 | 1.67 | 0.72 |
| 15:00 | 1.08 | 0.72 |
| 16:00 | 0.47 | 0.72 |
| 17:00 | 0 | 0.72 |
| 18:00 | 0 | 0.91 |
| 19:00 | 0 | 0.91 |
| 20:00 | 0 | 0.91 |
| 21:00 | 0 | 0.91 |
| 22:00 | 0 | 0.91 |
| 23:00 | 0 | 0.91 |
| Point | Stored energy |
|---|---|
| 00:00 | 0.7 |
| 01:00 | 0 |
| 02:00 | 0 |
| 03:00 | 0 |
| 04:00 | 0 |
| 05:00 | 0 |
| 06:00 | 0 |
| 07:00 | 0 |
| 08:00 | 0.4 |
| 09:00 | 1.3 |
| 10:00 | 2.7 |
| 11:00 | 4.3 |
| 12:00 | 5.8 |
| 13:00 | 7.2 |
| 14:00 | 8.1 |
| 15:00 | 8.4 |
| 16:00 | 8.2 |
| 17:00 | 7.4 |
| 18:00 | 6.5 |
| 19:00 | 5.5 |
| 20:00 | 4.5 |
| 21:00 | 3.6 |
| 22:00 | 2.6 |
| 23:00 | 1.7 |
- Used as it is made2,720 kWh (40%)
- Through the battery3,791 kWh (56%)
- Sent to the grid268 kWh (4%)
How this is calculated
Same need or same equipment
In Same need mode, each system is sized for your home. On-grid and hybrid match your yearly use, and off-grid must cover the darkest month. In Same equipment mode, all three use the size and battery you enter, which shows how each one uses the same solar.
Hour-by-hour energy flow
For a typical day in each month, solar first supplies the home, then charges any battery. Hybrid and on-grid systems export what is left. An off-grid system has nowhere to send it, so that energy is wasted once the battery is full.
Solar used = used as it is made + delivered by the battery
Cost over 25 years
We add the upfront price, one inverter replacement, yearly upkeep, one battery replacement around year 12, and the bills that remain. Prices are held flat, so this is a comparison and not a forecast.
25-year cost = price + replacements + upkeep + remaining bills × 25
Worked example: 600 kWh a month in Los Angeles
An on-grid system needs about 3.9 kW and costs about $10,300. A hybrid system adds a 13.5 kWh battery for about $23,400.
Off-grid needs about 6.7 kW and 33 kWh of batteries for about $51,600, and about 4,602 kWh of solar a year goes unused.
How accurate is this?
Generation comes from our solar model, which stays within 10% of PVGIS at 20 test cities. Energy flows use typical days, so they miss runs of cloudy weather. That matters most for off-grid homes, so we size them with a 25% margin. Battery and export prices are starting values, so replace them with your own.
Common mistakes
- Assuming on-grid solar keeps working in a power cut
- Comparing systems of different sizes without allowing for what each one supplies
- Sizing off-grid from yearly totals instead of the darkest month
- Forgetting that batteries need replacing during the system's life
Limits of this tool
- Typical days do not show several cloudy days in a row
- A generator or other backup for off-grid homes is not priced
- Prices and bills are held flat over 25 years
- Grid connection fees and local rules are not included
What to do next
- Get a closer price with the solar installation cost calculator
- Test the choice with the payback calculator
Frequently asked questions
What is the difference between on-grid, off-grid, and hybrid solar?
On-grid uses panels and the grid. Off-grid uses panels and batteries with no grid. Hybrid uses panels, batteries, and the grid.
Does on-grid solar work in a power cut?
Usually not. Grid-connected inverters shut down for the safety of people working on the lines, unless the system has a battery and backup equipment.
Is off-grid solar cheaper than on-grid?
It usually costs much more upfront, because it needs a larger array and a large battery to cover the darkest month and cloudy days.
Is a hybrid solar system worth it?
It depends on your power cuts, your export rate, and battery prices. A low export rate or frequent outages make a battery more useful.