Off-grid, RV & cabin
Enter both upfront costs and the grid's monthly bill. See your breakeven year and a full cost comparison out to 25 years.
How it works
Step 1
Total installed cost for the panels, battery, inverter, and labor.
Step 2
Your utility can provide both the extension cost and an estimated monthly bill for your expected usage.
Step 3
Know exactly when, if ever, off-grid's higher upfront cost gets paid back by avoided monthly bills.
For a $25,000 off-grid system against an $18,000 grid extension with a $100 monthly bill, the off-grid system breaks even in about 5.8 years, after which it continues saving money every year the grid connection would have kept costing. Beyond that breakeven point, the gap between the two options keeps widening in off-grid's favor for as long as the comparison runs. The federal ITC calculator turns this result into a concrete next step.
If your off-grid system costs less upfront than the grid extension, off-grid wins immediately with no breakeven period needed at all, since it costs less on day one and also avoids every future monthly bill the grid connection would have required. This outcome is common for properties with a long or geographically difficult grid extension distance, where utility line costs climb quickly with distance. Current figures live on the DOE's overview of grid deployment and transmission, which updates them when the program changes.
This comparison uses upfront system cost only and doesn't account for battery replacement, which off-grid systems typically need every 10 to 15 years depending on chemistry and usage patterns. A fully realistic financial comparison should factor in this recurring cost, which would extend the true off-grid breakeven point somewhat beyond what this simplified version shows. If you want to check this estimate against a second method, the roof space vs output estimator in our System Sizing section works from your daily load and peak sun hours.
This tool uses a flat monthly bill for simplicity, but electricity rates commonly rise over time due to inflation and utility rate increases, which would actually shorten the real breakeven period for off-grid compared to this straight-line estimate. If you want a more conservative, realistic projection, consider running this comparison again with a somewhat higher monthly bill figure to approximate future rate increases. EIA's Electric Power Annual report tracks how rates have actually moved over time if you want real historical data rather than a guess. Remote systems are easy to neglect. The annual maintenance cost estimator in our Maintenance & Lifespan section can help you budget for the maintenance that keeps output from slipping.
Compare against the off-grid vs grid extension cost comparison for a broader upfront-cost-only view, and check the grid extension cost per mile estimator if you don't yet have a firm quote from your utility. The grid-tie vs off-grid comparison tool in our grid and off-grid tools is worth a look too, since a grid-tied system with net metering is a third option this comparison doesn't cover. Off-grid systems commonly qualify for the same tax treatment as grid-tied ones, so check the federal ITC calculator in our rebates and incentives tools before finalizing either side of this comparison, and DOE's overview of grid deployment and transmission covers how utilities typically approach the extension side of the decision.
Questions
For a $25,000 off-grid system against an $18,000 grid extension with a $100 monthly bill, the off-grid system breaks even in about 5.8 years, after which it continues saving money every year the grid connection would have kept costing.
Then off-grid wins immediately with no breakeven period needed, since it costs less on day one and also avoids every future monthly bill the grid connection would have required. This is common for properties with a long or difficult grid extension distance.
No, this simplified comparison uses upfront system cost only. In practice, an off-grid system may need a battery replacement every 10 to 15 years depending on chemistry and usage, which adds a real ongoing cost that a full financial comparison should include.
Yes, if you want a more realistic long-term comparison. This tool uses a flat monthly bill for simplicity, but electricity rates commonly rise over time, which would shorten the actual breakeven period for off-grid compared to this straight-line estimate.