How many solar panels do I need for 1,000 kWh a month?

Data checked October 2026

Short answer

To cover 1,000 kWh a month (12,000 kWh a year) at a typical U.S. location (median state, 1,340 kWh per kW a year), you need about 9.2 kW — 21 × 440-W panels on roughly 565 sq ft of roof.

Math: 12,000 kWh ÷ 1,340 kWh per kW = 8.96 kW, rounded up to 21 whole 440-W panels (9.24 kW).
Production: about 12,382 kWh a year, 1,032 a month on average — more in summer, less in winter.
Panel size matters: 23 × 400-W or 20 × 460-W panels do the same job.
Typical price: about $23,747 at the $2.57/W national median, with no federal credit for a 2026 purchase.
1,000 kWh a month is above the U.S. average and typical of southern homes with central air.

Adjust it to your exact job

Your electricity use

I know my

Electricity use

kWh/mo

Use a 12-month average from your bill. U.S. homes averaged 874 kWh a month in 2025 (EIA).

Where and how

State

median state: 4.93 peak sun hours, 1,340 kWh per kW per year after 14% losses.

Panel wattage

Offset target

% of use

100% is typical where exports earn the retail rate.

You need about

9.2kW DC

21 × 440-W panels · 565 sq ft of usable roof · 12,382 kWh a year (103% of your use)

Production per year: 12,382kWha typical U.S. location, 20° south roof
Per month (average): 1,032kWhvs. 1,000 kWh used
Peak sun hours: 4.93h/dayPVGIS estimate
One panel makes: 1.62kWh/day590 kWh/yr
Panel area: 452sq ftmodules only
Typical price: $23,747at $2.57/W, before incentives

Same target, other panel sizes

Panels needed by wattage
Panel	Panels	System	Roof area
400 W	23	9.2 kW	563 sq ft
420 W	22	9.24 kW	565 sq ft
440 W	21	9.24 kW	565 sq ft
460 W	20	9.2 kW	563 sq ft

Export rules: 1:1 net metering

Varies by state and utility. The national default assumes 1:1 net metering, the best case — pick your state for its actual export rules.

What it pays back

The price of this system, the 2026 tax situation (the 30% federal credit ended for homeowner purchases completed after 2025) and your break-even year are in the solar payback calculator.

Shopping list

21 panels 440-W solar panels9.24 kW DC array
565 sq ft Usable roof area (incl. setbacks)

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Compare

1,000 kWh a month in different states (440-W panels, 100% offset)

State	kWh per kW	System kW	Panels	Roof sq ft
Arizona	1,755	7	16	431
California	1,677	7.5	17	457
Texas	1,421	8.8	20	538
Florida	1,455	8.4	19	511
North Carolina	1,446	8.4	19	511
New York	1,291	9.7	22	592
Massachusetts	1,302	9.2	21	565
Illinois	1,265	9.7	22	592
Washington	1,077	11.4	26	700

How this was worked out

Location changes the answer by about 63%: the same 1,000 kWh takes 16 panels in Arizona but 26 in Washington. At 9.2 kW this sits between the 7.7 kW median install (Berkeley Lab) and the 12 kW median quote (EnergySage).

Sun-hours check: 1,000 kWh a month is 32.9 kWh a day. With 4.93 peak sun hours and the 0.74 derate factor implied by the modeled yield (losses, inverter, heat), 32.9 ÷ (4.93 × 0.74) = 8.96 kW — the same answer.

Where exports earn less than retail (California, Arizona, Utah, Georgia and others), many installers size to about 70% of use: 6.6 kW here. Run the numbers in the solar payback calculator.

The full method, material data and tips are on the main solar panel calculator page.

Similar jobs

Other sizes people check

Sources

Data behind this answer

NLR (formerly NREL) PVWatts v8 — 14% losses, 20° tilt, south; kWh per kW DC by state city · checked October 2026
EU JRC PVGIS v5.3 (ERA5) — Fallback yields for states PVWatts was not fetched for (low confidence) · checked October 2026
EnergySage — best solar panels ranking — Top residential panels 430–460 W, 22–23% efficient · checked October 2026
Berkeley Lab — U.S. Distributed Solar and Storage Data, 2026 update — $3.6/W host-owned median; 7.7 kW median; roof coverage 22–31% · checked October 2026
EIA-861 2025 (average monthly bill and use) — U.S. average 874 kWh/month; state averages · checked October 2026
EIA Electric Power Monthly, Table 5.6.B — Residential price by state, Jan–Aug 2026 · checked October 2026
EnergySage H1 2026 marketplace report (via Mercom) — $2.57/W median; batteries $1,130/kWh · checked October 2026
EnergySage — solar rebates and incentives by state — State credits, rebates and export rules · checked October 2026
NLR PV Fleet Performance study (OSTI 1864619) — Degradation 0.5%/yr default; 0.88%/yr hot climates · checked October 2026

Short answer

To cover 1,000 kWh a month (12,000 kWh a year) at a typical U.S. location (median state, 1,340 kWh per kW a year), you need about 9.2 kW — 21 × 440-W panels on roughly 565 sq ft of roof.

Math: 12,000 kWh ÷ 1,340 kWh per kW = 8.96 kW, rounded up to 21 whole 440-W panels (9.24 kW).

Production: about 12,382 kWh a year, 1,032 a month on average — more in summer, less in winter.

Panel size matters: 23 × 400-W or 20 × 460-W panels do the same job.

Typical price: about $23,747 at the $2.57/W national median, with no federal credit for a 2026 purchase.

1,000 kWh a month is above the U.S. average and typical of southern homes with central air.

Adjust it to your exact job

Your electricity use

I know my

Electricity use

kWh/mo

Use a 12-month average from your bill. U.S. homes averaged 874 kWh a month in 2025 (EIA).

Where and how

State

median state: 4.93 peak sun hours, 1,340 kWh per kW per year after 14% losses.

Panel wattage

Offset target

% of use

100% is typical where exports earn the retail rate.

You need about

9.2kW DC

21 × 440-W panels · 565 sq ft of usable roof · 12,382 kWh a year (103% of your use)

Production per year: 12,382kWha typical U.S. location, 20° south roof
Per month (average): 1,032kWhvs. 1,000 kWh used
Peak sun hours: 4.93h/dayPVGIS estimate
One panel makes: 1.62kWh/day590 kWh/yr
Panel area: 452sq ftmodules only
Typical price: $23,747at $2.57/W, before incentives

Same target, other panel sizes

Panels needed by wattage
Panel	Panels	System	Roof area
400 W	23	9.2 kW	563 sq ft
420 W	22	9.24 kW	565 sq ft
440 W	21	9.24 kW	565 sq ft
460 W	20	9.2 kW	563 sq ft

Export rules: 1:1 net metering

Varies by state and utility. The national default assumes 1:1 net metering, the best case — pick your state for its actual export rules.

What it pays back

The price of this system, the 2026 tax situation (the 30% federal credit ended for homeowner purchases completed after 2025) and your break-even year are in the solar payback calculator.

Shopping list

21 panels 440-W solar panels9.24 kW DC array
565 sq ft Usable roof area (incl. setbacks)

State

kWh per kW

System kW

Panels

Roof sq ft

Arizona

1,755

431

California

1,677

7.5

457

Texas

1,421

8.8

538

Florida

1,455

8.4

511

North Carolina

1,446

8.4

511

New York

1,291

9.7

592

Massachusetts

1,302

9.2

565

Illinois

1,265

9.7

592

Washington

1,077

11.4

700

How this was worked out

Where exports earn less than retail (California, Arizona, Utah, Georgia and others), many installers size to about 70% of use: 6.6 kW here. Run the numbers in the solar payback calculator.

The full method, material data and tips are on the main solar panel calculator page.