U.S.-focused solar planning hub
Solar PV calculators and charts
Start with solar production, system size, battery backup, inverter checks, and payback. This hub brings the main solar calculators, charts, and guides into one place.
- Core workflows
- 8
- Solar charts
- 23
- Planning basis
- U.S.
Core solar calculators
Use these entry points for the most common solar planning questions.
Economics
Solar ROI and Payback Calculator
Estimate payback from production, self-consumption, export credit, user-entered incentives, O&M, degradation, and replacement.
System size
Solar System Sizing Calculator
Size a PV array from monthly kWh, target offset, peak sun hours, system losses, degradation, and roof-area limits.
Layout
Solar Row Spacing Calculator
Check PV row pitch, inter-row shadow length, solar altitude, and ground coverage ratio before layout review.
Protection
Solar Combiner Sizing Calculator
Check PV source-circuit current, string OCPD review points, combiner output current, and inverter input-current limits.
Storage
Battery Capacity Calculator
Convert critical loads, autonomy, DoD, efficiency, battery voltage, and unit ratings into kWh, Ah, and module count.
PV strings
Inverter Sizing Calculator
Check PV inverter AC size, DC/AC ratio, and cold-weather string-count assumptions from module data.
Conductors
DC Voltage Drop Calculator
Check PV source-circuit, combiner, battery-side, and other DC conductor runs for voltage drop and wire loss.
AC output
Wire Size Calculator
Check inverter AC output conductors from current, phase, distance, material, ampacity basis, and voltage-drop target.
Choose by job task
The solar hub groups practical tasks: production, system sizing, layout, protection, conductors, backup, and economics.
Plan production and system size
Estimate production from monthly kWh, solar-resource data, peak sun hours, orientation, losses, degradation, and selected long-term output cases.
System size
Solar System Sizing Calculator
Size a PV array from monthly kWh, target offset, peak sun hours, system losses, degradation, and roof-area limits.
Chart
Solar Resource Peak Sun Hours Chart
Document PVWatts, NSRDB, peak sun hours, tilt, azimuth, date retrieved, and seasonal basis.
Chart
Solar Tilt Orientation Sensitivity Chart
Compare tilt, azimuth, shade, losses, seasonal objective, and scenario comparison before ROI or system sizing.
Chart
Solar Production Losses Performance Ratio Chart
Document soiling, temperature, inverter, wiring, mismatch, clipping, snow, availability, and performance ratio.
Chart
Solar Degradation Year-N Production Chart
Document degradation, year-N kWh, year-25 output, maintenance, replacement, ROI, emissions, storage, and warranty review notes.
Chart
Solar Panel Output Chart
Document panel watts, panel count, peak sun hours, losses, first-year production, and year-25 kWh.
Review layout and row shading
Convert tilt, row length, and solar altitude into minimum pitch and GCR.
Review strings, combiner, and protection
Connect string voltage, parallel-string current, OCPD review points, and equipment input-current limits.
PV strings
Inverter Sizing Calculator
Check PV inverter AC size, DC/AC ratio, and cold-weather string-count assumptions from module data.
Protection
Solar Combiner Sizing Calculator
Check PV source-circuit current, string OCPD review points, combiner output current, and inverter input-current limits.
Chart
Solar Combiner Sizing Chart
Document Isc, parallel strings, source current, OCPD review points, and AHJ follow-up.
Review PV cable and voltage drop
Separate DC string routes from inverter AC output before checking ampacity, terminals, derating, and listed equipment.
Conductors
DC Voltage Drop Calculator
Check PV source-circuit, combiner, battery-side, and other DC conductor runs for voltage drop and wire loss.
AC output
Wire Size Calculator
Check inverter AC output conductors from current, phase, distance, material, ampacity basis, and voltage-drop target.
Chart
Solar Cable Voltage Drop Chart
Document PV current, conductor material, route length, voltage drop, terminal temperature, derating, and listed-equipment checks.
Plan battery backup
Convert critical loads, autonomy, voltage, and battery unit data into capacity and module count.
Review solar economics
Separate ROI, O&M, monitoring, warranty, inventory, and owner-review assumptions so costs, risks, and follow-up items stay clear.
Economics
Solar ROI and Payback Calculator
Estimate payback from production, self-consumption, export credit, user-entered incentives, O&M, degradation, and replacement.
Chart
Solar ROI Payback Chart
Organize cost, production, self-consumption, export credit, O&M, replacement, and payback assumptions.
Chart
Solar Operations Maintenance Replacement Cost Chart
Document cleaning, inspection, monitoring, inverter replacement, module replacement, downtime, truck roll, O&M budget, and lifecycle cost.
Chart
Solar Monitoring Availability Performance Issue Log Chart
Document monitoring alerts, availability events, outage windows, corrective actions, measured-vs-modeled output, warranty evidence, and production-loss diagnosis.
Chart
Solar Measured Production Normalization Weather Adjustment Chart
Document measured production normalization, weather adjustment, meter boundary, review period, degradation basis, model comparison, and performance ratio.
Chart
Solar Performance Ratio Trend Fleet Benchmarking Chart
Document normalized performance ratio trend, monthly comparison, seasonal comparison, array benchmark, site benchmark, fleet benchmark, benchmark source, and data-quality limits.
Chart
Solar Portfolio Reporting Owner Review Pack Chart
Document owner production summary, normalized PR trend, O&M actions, ROI inputs, emissions inputs, storage assumptions, open risks, and next-review date.
Chart
Solar Commissioning and Owner Acceptance Checklist
Document as-built package, monitoring access, meter boundary, warranty documents, O&M contacts, spare parts, open action items, owner acceptance, and first-review date.
Chart
Solar Service Contract SLA Preventive Maintenance Schedule Chart
Document service scope, SLA response time, inspection cadence, monitoring review cadence, cleaning criterion, spare-parts responsibility, warranty escalation, exclusions, price basis, and renewal date.
Inventory
Solar Spare Parts Inventory Critical Replacement Planning Chart
Document spare part type, criticality, compatible equipment, replenishment period, minimum and maximum stock, storage conditions, warranty status, reorder point, owner responsibility, and replacement priority.
Claim
Solar Warranty Claim Documentation Chart
Document claim criterion, affected equipment, serial numbers, monitoring evidence, warranty documents, service notes, manufacturer case details, replacement part status, owner approval, and claim status.
Repair
Solar Corrective Action Repair Completion Return To Service Verification Chart
Document corrective action, repair authorization, replacement part installed, service date, post-repair monitoring, return-to-service status, owner signoff, documentation update, follow-up interval, and unresolved risk.
Chart
Solar Degradation Year-N Production Chart
Keep year-N kWh, year-25 output, maintenance, replacement, and warranty notes visible before cash-flow review.
Compare solar, storage, and EV charging
Keep user-entered tariff assumptions, storage dispatch, demand-charge reduction, and EV charging margin as a scenario worksheet, not an optimizer.
Economics
Solar ROI and Payback Calculator
Estimate payback from production, self-consumption, export credit, user-entered incentives, O&M, degradation, and replacement.
Storage
Battery Capacity Calculator
Convert critical loads, autonomy, DoD, efficiency, battery voltage, and unit ratings into kWh, Ah, and module count.
Chart
Solar Storage EV Economics Worksheet
Document solar-only, solar plus storage, and solar plus storage plus EV charging with user-entered assumptions.
Document avoided emissions
Convert solar kWh into avoided CO2e only after recording the entered factor, region, data year, and date retrieved.
Solar charts and worksheets
Use these references after a calculator result to document assumptions before equipment selection, electric utility checks, or installer quote checks.
Resource
Solar Resource Peak Sun Hours Chart
NREL PVWatts, NSRDB, peak sun hours, tilt, azimuth, date retrieved, and seasonal boundary.
Sensitivity
Solar Tilt Orientation Sensitivity Chart
Tilt, azimuth, shade, losses, seasonal objective, and scenario comparison before selecting production kWh.
Losses
Solar Production Losses Performance Ratio Chart
Soiling, temperature, inverter, wiring, mismatch, clipping, snow, availability, and performance ratio.
Long term
Solar Degradation Year-N Production Chart
Degradation, year-N kWh, year-25 output, maintenance, replacement, ROI, emissions, storage, and warranty review notes.
O&M
Solar Operations Maintenance Replacement Cost Chart
Cleaning, inspection, monitoring, inverter replacement, module replacement, downtime, truck roll, O&M budget, and lifecycle cost.
Monitoring
Solar Monitoring Availability Performance Issue Log Chart
Monitoring alerts, availability events, outage windows, corrective actions, measured-vs-modeled output, warranty evidence, and production-loss diagnosis.
Measured
Solar Measured Production Normalization Weather Adjustment Chart
Measured production normalization, weather adjustment, meter boundary, review period, degradation basis, model comparison, and performance ratio.
Benchmark
Solar Performance Ratio Trend Fleet Benchmarking Chart
Normalized performance ratio trend, monthly comparison, seasonal comparison, array benchmark, site benchmark, fleet benchmark, benchmark source, and data-quality limits.
Review
Solar Portfolio Reporting Owner Review Pack Chart
Owner production summary, normalized PR trend, O&M actions, ROI inputs, emissions inputs, storage assumptions, open risks, and next-review date.
Acceptance
Solar Commissioning and Owner Acceptance Checklist
As-built package, monitoring access, meter boundary, warranty documents, O&M contacts, spare parts, open action items, owner acceptance, and first-review date.
Service
Solar Service Contract SLA Preventive Maintenance Schedule Chart
Service scope, SLA response time, inspection cadence, monitoring review cadence, cleaning criterion, spare-parts responsibility, warranty escalation, exclusions, price basis, and renewal date.
Inventory
Solar Spare Parts Inventory Critical Replacement Planning Chart
Spare part type, criticality, compatible equipment, replenishment period, minimum and maximum stock, storage conditions, warranty status, reorder point, owner responsibility, and replacement priority.
Warranty
Solar Warranty Claim Documentation Chart
Claim criterion, affected equipment, serial numbers, monitoring evidence, warranty documents, service notes, manufacturer case details, replacement part status, owner approval, and claim status.
Production
Solar Panel Output Chart
Panels, watts, sun hours, losses, first-year production, and year-25 kWh.
Sizing
Solar System Sizing Chart
Monthly load, target offset, PVWatts losses, PV size, panel count, production, and roof area.
Layout
Solar Row Spacing Chart
Solar altitude, tilt, row length, shadow length, row pitch, and GCR.
Protection
Solar Combiner Sizing Chart
Isc, parallel strings, string fuses, combiner output current, and AHJ follow-up.
PV cable
Solar Cable Voltage Drop Chart
PV current, material, route length, voltage drop, terminals, derating, and listed equipment.
ROI
Solar ROI Payback Chart
Cost, user-entered incentives, self-consumption, export credit, O&M, replacement, and payback.
Emissions
Solar Emissions Reduction Chart
PV kWh, user-entered emission factor, region, data year, date retrieved, and avoided CO2e.
Storage EV
Solar Storage EV Economics Worksheet
User-entered tariff assumptions, storage dispatch, demand-charge reduction, EV charging margin, and scenario comparison.
Battery
Battery Capacity Runtime Chart
Usable capacity, battery voltage, DoD, efficiency, series count, parallel strings, and modules.
Inverter
Inverter Sizing Chart
Continuous watts, surge, DC voltage, strings, and equipment-data review.
Plan the Next Check. Use the result to compare system size, battery capacity, inverter range, ROI, or worksheet values before reviewing a quote, model, or equipment submittal.
Use the result to compare system size, battery capacity, inverter range, ROI, or worksheet values before reviewing a quote, model, or equipment submittal.
Keep the inputs with the result so the load profile, solar resource, equipment rating, and review date stay clear for the next step.