Home Energy & Solar

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Estimate appliance kWh and cost by day, week, average month, current calendar month, and year, with an optional regional CO₂ factor.

Calculate an entered utility bill reduction and simple payback, or compare observed bill averages without assuming what caused the change.

Calculate water use from meter readings or measured fixture activity, compare daily averages and estimate variable charges using your actual rate.

Calculate emissions from your activity quantities and documented factors. Record units, sources and boundaries, then save, restore or export.

Calculate a transparent solar-array nameplate and energy scenario from entered panel count, peak sun hours, losses, and annual site electricity.

Test a solar cash-payback scenario from entered all-in cost, verified incentives, tariff-aware year-one savings, recurring costs, and horizon.

Build an installed quote, compare lifetime costs and calculate material packs. Separate payment-day cash from later reimbursements using your project records.

Model one rain event with catchment area, runoff assumptions, first-flush diversion and available tank space. Inspect retained inflow and overflow.