Does Your Off-Grid Solar System Balance Each Day?
Compare daily solar generation with electrical demand and estimate how much battery energy is available after reserve and storage losses.
What an off-grid energy balance tells you
An off-grid system must produce enough energy over time to serve its loads and replenish storage. A daily surplus is useful, but it does not guarantee resilience during cloudy periods or unusual demand.
Why battery capacity and battery power are different
Battery capacity determines how much energy can be stored. Battery and inverter power limits determine how quickly that energy can be delivered. This calculator focuses on the energy side.
Reserve energy changes autonomy
A protected reserve intentionally holds some stored energy back. This reduces immediate usable autonomy while maintaining a buffer for future needs.
Why a sunless-day test is useful
A system that balances on a sunny average day may still fail during several low-generation days. Applying a sunless-day scenario provides a simple stress test, though it is not a weather forecast.
FAQs
Does daily surplus mean the system is off-grid safe?
No. Timing, weather and battery power limits also matter.
Should I use average solar generation?
For initial screening, yes. For design, use a location-specific generation profile and seasonal analysis.
Does the tool include generator backup?
No. A hybrid generator model is a separate decision and dispatch problem.
Can the battery charge from the grid?
This analyzer assumes an off-grid solar-plus-storage energy path and does not model grid charging.