Solar Hot-Water Load and System Planning

Calculate water-heating load, whole collector count and a storage/recovery window from actual volumes, temperatures, useful yield and candidate equipment.

Calculate stored water and ideal purge time from actual pipe inside diameters, then record measured arrival time, volume and the stated temperature criterion.

Look up NASA POWER monthly horizontal solar climatology by coordinates, preview and explicitly apply the data, or summarize a documented manual monthly series.

Calculate useful daily heat from a supported net efficiency or apply a documented collector gain/loss curve at one operating point; report kWh and BTU.

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Evaluate dated annual solar cash flows or an explicit escalation scenario, including replacements, discounting and recovery that can reverse later.

Compare annual EV energy offset and interval solar charging availability using vehicle acceptance, charging losses, other loads and actual site output.

Check configured EVSE AC current against ordinary circuit limits, then estimate charging energy and time using vehicle acceptance and efficiency.

Estimate instantaneous PV power from operating conditions or integrate actual AC intervals; keep module temperature, inverter clipping and energy separate.

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

Value self-used solar and exported energy with their own rates, realizable credits and additional charges; retain the actual tariff assumptions.

Compare two actual inverter proposals using quoted costs, modeled annual energy, self-use and realizable export value; show the incremental cost and benefit.

Calculate an explicit annual-decline energy scenario or annualized change between normalized measurements; handle zero decline, zero output and measured growth.

Compare net upfront cost with constant annual benefits and costs; handle zero outlay, nonpositive savings and the chosen horizon explicitly.