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SolarCalcNow

1500 kWh/month preset

Solar Calculator for 1500 kWh per Month

Start with 1500 kWh/month pre-filled and test how state production, shade, export value, and offset change the result.

Estimate a higher-usage home at 1500 kWh/month, while keeping future loads and current billed consumption clearly separated.

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Estimate solar for 1500 kWh/month

Enter monthly kWh or electric bill. The calculator uses state-level assumptions and shows the math behind the result.

Planning for new electric loads?

Add a simple monthly usage placeholder before sizing solar. Replace it with your actual bill or device estimate when you have it.

Need more than a placeholder? Calculate EV charging from annual miles and efficiency, then compare current and future solar size. Plan EV and other future home loads

Your estimate

Example result

You likely need 31-35 panels

Estimated system size: 13.1 kW. This is an estimate, not an installer quote.

Confidence

Medium

Planning estimate only — not an installer quote, engineering design, or tax advice.

Payback uses gross system cost before verified incentives, financing fees, batteries, and roof work.

Estimated system size
13.1 kW
Sized for your target offset and system loss assumption.
Likely panel count
31-35
Centered around 33 panels at 400W equivalent.
Roof space
797 sq ft
Includes a spacing factor, not a final layout plan.
Annual production
18,000 kWh
Modeled first-year output at the selected offset; not a production guarantee.
Gross cost
$30,741 - $39,898
Before verified incentives, financing, or battery costs.
Gross cost per watt
$2.35 - $3.05
Before incentives. Useful for comparing installer quotes.
Annual savings
$4,489
Based on state residential rate and self-consumption assumption.
Payback
6.8 years - 8.9 years
Simple gross-cost payback estimate.

Annual usage: 18,000 kWh

Annual production target: 18,000 kWh

State rate: 35.25 cents/kWh

Export assumption: Partial export credit

Direct solar use: 9,900 kWh

Modeled exports: 8,100 kWh

Panel count view

31-35 panels

Estimate shape

Production, savings, and payback

Annual production target18,000 kWh
Annual savings$4,489
Payback6.8 years - 8.9 years

Privacy note: the printable report link stores estimate inputs in the URL, including ZIP and usage or bill values. Keep it private if those details are sensitive.

Local scenarios

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Saved scenarios stay in this browser only and may include ZIP, bill, and usage inputs. SolarCalcNow does not sync them or send those values to analytics.

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Assumptions behind this estimate
  • California state-level electricity rate and solar production defaults are used.
  • 100% bill offset target.
  • 400W solar panels.
  • 14% system loss assumption.
  • Roof area uses about 21 sq ft per panel plus spacing factor.
  • Gross cost range excludes verified incentives, financing, batteries, roof work, and panel upgrades.
  • 55% of annual solar production is modeled as directly used before export.
  • Export value assumption: Partial export credit.
  • Savings are energy-only and exclude fixed charges, minimum bills, demand charges, and time-of-use detail.
  • You provided monthly kWh usage.
  • State production defaults are used for this estimate.

Confidence drivers

  • Overall confidence: Medium.
  • You provided monthly kWh usage.
  • State production defaults are used for this estimate.

Expected production: 18,000 kWh

System loss: 14%

Export value: Partial export credit

Direct solar use: 9,900 kWh

Modeled exports: 8,100 kWh

State production default: 1,600 kWh/kW/year

SolarCalcNow provides planning estimates only. Results are not installer quotes, engineering designs, tax advice, financing recommendations, or utility interconnection approval.

Optional next step

Want installer quotes based on this estimate?

Your estimate stays visible. This form is optional and uses explicit consent.

Installer quote matching is not active yet. You can still calculate, save, and print your estimate before contacting installers directly.

For a home using 1,500 kWh per month in California, the default planning estimate is a 13.1 kW system with 31-35 panels at 400 W each, producing about 18,000 kWh per year and needing roughly 797 sq ft of roof. Estimated gross cost is $30,741-$39,898 before incentives, with simple payback of 6.8 years-8.9 years. The estimate uses EIA Electric Power Monthly, Table 5.6.A, April 2026 residential price (updated 2026-06-25) and PVWatts-style starter production assumption (updated 2026-07-22).

SolarCalcNow provides planning estimates only. Results are not installer quotes, engineering designs, tax advice, financing recommendations, or utility interconnection approval.

Real baseline

What the calculator returns for 1500 kWh/month

Same inputs, different state data: 400 W panels, 1500 kWh/month, low shade, 100% offset target, partial export credit, and no ZIP-level PVWatts override. This makes the state-rate and production assumptions visible before a quote.

StateSystemPanelsGross costPayback
California13.1 kW31-35$30,741-$39,8986.8 years-8.9 years
Texas14.0 kW33-37$32,791-$43,25615.2 years-20.0 years
Massachusetts16.7 kW40-44$46,047-$61,11612.3 years-16.3 years

Methodology first

1500 kWh/month needs a load-aware review

Read methodology

1500 kWh per month can represent a larger home, substantial cooling, electric water heating, an EV, or several electric loads combined. The number alone does not identify which loads create the demand.

Review the annual pattern before sizing. A future EV or heat pump should be modeled as a separate load so an installer cannot hide an unexplained usage increase inside the production target.

Compare planning presets

Same calculator engine with a different starting assumption. Useful before comparing installer quotes.

State calculators

Start with local assumptions

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FAQ

Common solar calculator questions

Is 1500 kWh per month the right solar-planning baseline for my home?

Use 1500 kWh only when it is reasonably close to the annual average shown by your utility bills. The calculator multiplies monthly usage by twelve, applies the selected offset target, and sizes the system from the state production assumption after shade and system losses. A single high summer or winter bill can overstate the year-round requirement, while a mild month can understate it. Average a full year when possible, keep future electric loads separate until they are understood, and compare the result with your available roof. This preset is a starting input, not evidence that every home at this usage needs the same design.

What should I change after running the 1500 kWh preset?

Replace the preset with your own monthly kWh first, then select the correct state and review shade, panel wattage, target offset, direct solar use, and export value. Those controls affect different parts of the result: production assumptions influence system size, panel wattage converts system watts into panel count, and export value changes annual savings without changing the energy the system is asked to produce. Check the visible source dates and confidence notes before comparing quotes. The displayed cost is gross cost before incentives, financing, batteries, roof work, or electrical upgrades, so an installer proposal should keep those items separate rather than presenting one unexplained net figure.

What to do next

After calculating, save the estimate assumptions, check incentive status, and compare installer quotes against the same baseline.