Rooftop Solar Site and Proposal Planning

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

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

Convert daily solar irradiation into equivalent peak-sun-hours or integrate measured irradiance intervals; preserve the actual plane and period.

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

Compare actual tilt and azimuth candidates using interval irradiance or entered modeled yields; retain the tested period, feasible tilt limits and tied results.

Compare PV DC/AC nameplate ratio, simultaneous AC watts and VA, timed peak ratings and the actual battery-voltage and current envelope.

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

Correct module Voc and Vmp at design temperatures and find whole series/parallel strings within startup, MPPT, absolute-voltage and current limits.

Compare documented cable candidates for loop voltage drop, loss, adjusted ampacity, terminal current and maximum circuit voltage without a fallback gauge.

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

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

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

Size whole PV modules for a daily load and recharge target, then track chronological battery SOC, unmet load and curtailed energy within operating limits.

Size nominal battery Wh and Ah from AC/DC loads, conversion losses and the actual SOC window; compare finite whole-unit series and parallel arrangements.

Calculate charge used between states of charge and record equivalent full discharges from measured throughput; keep capacity basis and limits explicit.

Check MPPT or PWM input voltage, short-circuit current, operating current and battery charging constraints; separate output clipping from input-limit failures.

Value recoverable soiling losses for an entered period using the correct clean or soiled energy baseline, self-use, export credits and cleaning cost.

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

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.

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.

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.