How Many Panels Does It Take to Power a House? A Street? New York? US? The World?

Updated: Sep 24, 2026
8 min

Short version first: a typical American home runs on somewhere between 9 and 18 solar panels. That's the real answer to the question most people are actually asking. Everything else in this article is what happens when you keep asking that same question at a bigger scale, until you're trying to cover the entire planet in solar panels. Let's do the math.

Home Solar System: 9-18 panels

Modern residential panels are rated between about 400 and 600 Watts, with a handful of 2026 high-output models pushing past 750 Watts. How much energy one panel produces in a day depends on more than its wattage, though. Positioning, shading, weather, and the number of peak sun hours in your area all matter. Peak sun hours aren't the same as daylight hours: they measure the time a panel gets strong enough sunlight to work at close to full output.

Pannel wattage	Pannels needed for a 7 kW system
400 W	18
500 W	14
600 W	12
750 W	9

City	Average peak sun hours/day
Phoenix, AZ	~6.5
Los Angeles, CA	~5.6
New York, NY	~3.8
Seattle, WA	~3.7

Commercial Solar Systems: From a Hundred to Thousands of Panels

There's no single legal definition of a commercial solar project, but systems above roughly 15 kilowatts are generally treated as commercial. They use higher-output panels than a home system and can take months or years to build.

Powering a Street or Small Town: 1,400-2,000 Panels

Once you're trying to power an entire street or neighborhood, you need megawatts, which means you need a solar farm. One megawatt of solar, including access roads and spacing between rows, typically takes 5 to 10 acres of land. Building it out requires roughly 1,400 to 2,000 panels, depending on wattage.

Built somewhere sunny, that 1-megawatt farm produces around 5 megawatt-hours a day, enough for about 150 average homes. Call it a small village, or one long city street.

Powering New York State: Around 200 Million Panels

What about a big, real place, like New York? Fair warning: everything from here on is a deliberate oversimplification. Powering a state or country entirely on solar isn't a realistic near-term project, so we're ignoring transmission losses, storage, and how demand shifts by season and time of day. This is just a way to grasp the scale.

New York State used about 140.5 terawatt-hours of electricity in 2024, according to the EIA's state electricity profile. That's roughly 385 gigawatt-hours a day. With the state's average of 3.8 peak sun hours, an all-solar system would need to be about 101 gigawatts.

Built with 500-Watt panels, that's around 200 million panels; with higher-output 700-Watt modules, closer to 145 million. At 5 acres per megawatt, the system would need about 790 square miles of land, roughly a dozen Washington, DCs side by side.

123 GW

US utility-scale solar capacity, end of 2024 (EIA)

US utility-scale solar capacity had already reached about 123 GW by the end of 2024, according to EIA's Electric Power Annual data — more than the roughly 101 GW our hypothetical all-solar New York would need. The industry kept moving in 2025, adding another 43 GW nationwide, per SEIA.

United States on Solar: Around 4 Billion Panels

Since we've already covered one state, why not the whole country? The US consumed about 3,975 terawatt-hours of electricity in 2024, per EIA data, or a little under 11 terawatt-hours a day.

Deploy the system somewhere sunny, at 5 peak sun hours a day, and you'd need about 2.2 terawatts of solar. That works out to somewhere between 3 and 5.5 billion panels, landing close to 4 billion at a typical 500-Watt panel. Building it would take around 17,000 square miles of land, close to the combined area of Massachusetts, Connecticut, and Rhode Island.

World on Solar Energy: Tens of Billions of Panels

Last one: the entire planet. According to the IEA's Global Energy Review, global electricity consumption rose by about 1,080 terawatt-hours (+4.3%) in 2024. Working back from those two figures puts total consumption at roughly 26,000 terawatt-hours for the year, our own estimate rather than a number the IEA states outright. That's just over 71 terawatt-hours needed per day.

Build the array in a desert getting 7 hours of full sun a day, and you'd need a 10-terawatt system. Panel count comes out somewhere between 14 and 26 billion, depending on wattage. Land required: around 80,000 square miles, noticeably bigger than North Dakota or Missouri, if you tried to cover either state entirely.

3 TW

global installed solar capacity by early 2026

Here's the part worth sitting with: back when this kind of forecasting was being done, the industry expected global solar capacity to hit 2.3 terawatts by 2025. It actually blew past that. The world installed a record 664 GW of new solar in 2025 alone, and cumulative capacity crossed 3 terawatts in early 2026, tripling in just four years, according to SolarPower Europe's own report. We're still a long way from a fully solar-powered world, but the industry has consistently grown faster than its own predictions.

The Whole Picture at a Glance

Scale	Panels needed*	System size	Land area
Average US home	9-18	~7 kW	Rooftop
Small town / long street	1,400-2,000	1 MW	5-10 acres
New York State	145-200 million	~101 GW	~790 sq mi
United States	3-5.5 billion	~2.2 TW	~17,000 sq mi
The world	14-26 billion	~10 TW	~80,000 sq mi

*Ranges reflect panel wattage, from roughly 400 W to 750 W.

Efficiency remains the one place solar still lags behind other energy sources: you need real land to build a serious installation. That keeps improving as panels get more powerful per square foot, which is exactly why the wattage numbers in this article look different than they would have a couple of years ago

FAQ

How many solar panels does it take to power a house?

Most US homes need 9 to 18 panels, depending on wattage and location. A 500-Watt panel in a sunny climate gets you toward the low end; lower-wattage panels or a cloudier climate push it higher.

How many solar panels would it take to power a street or small town?

Around 1,400 to 2,000 panels, built as a 1-megawatt solar farm on 5 to 10 acres. That's enough for roughly 150 average homes.

How many solar panels would it take to power New York State?

Somewhere between 145 and 200 million, spread across about 790 square miles. New York's own utility-scale solar capacity covers a small fraction of that today.

How many solar panels would it take to power the United States?

Somewhere around 4 billion, give or take depending on wattage, spanning roughly 17,000 square miles of land.

How many solar panels would it take to power the world?

Between 14 and 26 billion, needing about 80,000 square miles of desert-grade sun. Global solar capacity, at 3 terawatts, is still a fraction of the roughly 10 terawatts that would take.