Georgia Solar Calculator

Solar Calculator Form

Use the form below. Results will appear above this section after submission.

Monthly Usage (kWh)

Enter your average monthly electricity use.

Utility Rate ($/kWh)

Enter your retail electricity price.

Peak Sun Hours

Use your site estimate or installer value.

Panel Wattage (W)

Typical modern panels range widely.

Panel Count

Use the planned number of panels.

Performance Ratio

Accounts for system losses.

Self-Use Ratio

Portion of solar used onsite.

Export Credit Rate ($/kWh)

Credit received for exported energy.

Installed Cost ($/W)

Use your quote or planning estimate.

Upfront Incentive (%)

Enter total percent incentive reduction.

Annual Degradation (%)

Expected output decline per year.

Utility Escalation (%)

Expected annual utility price growth.

Reset

Plotly Graph

This chart estimates monthly solar production from your annual output.

Example Data Table

Scenario	Panels	Panel Watt	Sun Hours	Rate	Performance Ratio	Estimated Annual Output
Compact Home	14	430 W	4.9	$0.14	0.80	8,607 kWh
Family Home	20	450 W	5.0	$0.14	0.82	13,469 kWh
Large Roof	28	460 W	5.1	$0.15	0.84	20,211 kWh

Formula Used

1) System Size

System Size (kW) = Panel Count × Panel Wattage ÷ 1000

2) Daily Solar Output

Daily Output (kWh) = System Size × Peak Sun Hours × Performance Ratio

3) Annual Solar Output

Annual Output (kWh) = Daily Output × 365

4) Self-Use and Export Split

Self-Used Energy = Annual Output × Self-Use Ratio

Exported Energy = Annual Output − Self-Used Energy

5) Annual Savings

Annual Savings = (Self-Used Energy × Utility Rate) + (Exported Energy × Export Credit Rate)

6) Installed Cost and Incentive

Gross Cost = System Size × 1000 × Cost per Watt

Net Cost = Gross Cost − (Gross Cost × Incentive %)

7) Simple Payback

Payback Period = Net Cost ÷ Annual Savings

8) Long-Term Savings

Each year adjusts output by degradation and value by utility escalation before adding cumulative savings.

How to Use This Calculator

Enter your monthly electricity use in kilowatt-hours.
Enter your electricity rate in dollars per kilowatt-hour.
Add peak sun hours for your property estimate.
Enter panel wattage and total panel count.
Choose a performance ratio for expected system losses.
Set self-use ratio to reflect how much solar you consume onsite.
Enter export credit rate for energy sent to the grid.
Enter installed cost, incentive percentage, degradation, and utility escalation.
Click the calculate button.
Review output, savings, payback, and the Plotly chart above the form.

Frequently Asked Questions

1) Is this calculator exact?

No. It gives planning estimates from your inputs. Real production changes with roof tilt, azimuth, shading, weather, inverter losses, utility rules, and installation quality.

2) Should I use AC or DC system size?

Use panel wattage and panel count as sold values. The calculator converts them into DC system size, then applies performance ratio to estimate usable energy.

3) What is performance ratio?

It represents losses from heat, wiring, inverter conversion, dust, mismatch, and downtime. Typical planning values often range near 0.75 to 0.90, but your installer may model it differently.

4) How should I set self-use ratio?

Use a higher value when most daytime solar serves your home directly. Use a lower value when you export more energy or rely on evening consumption.

5) What export rate should I enter?

Enter the credit you expect for exported electricity. Some plans credit less than full retail. Use your utility documents or installer proposal for the best number.

6) Does it include batteries?

Not directly. You can approximate battery benefits by increasing self-use ratio and adjusting export rate. For battery economics, add separate storage cost and savings analysis.

7) Why is payback different from lifetime savings?

Payback measures how long net cost takes to recover. Lifetime savings estimates total value over many years, including degradation and utility price escalation.

8) Can I use this outside Georgia?

Yes. Replace sunlight, rates, incentives, and export assumptions with local values. The math is location-agnostic, while the page label simply targets Georgia users.