How Much Power Does A Solar Panel Produce?

The average solar panel produces 420 kilowatt hours per year in the US

A typical American home’s annual electricity consumption is 10,632 kWh

The most powerful solar panel is Jinko Solar’s Tiger Neo N-type 72HL4

Solar panels can cut your energy bills, reduce your carbon footprint, and raise your house’s value – but before you buy, you’ll want to understand what you’re purchasing.

You need to know how to tell the power rating of a solar panel, how much electricity you can expect to generate with your panels, and how to produce as much as you need.

Thankfully, we’ve got you covered with this guide to solar panel power.

solar panels on a gray roof under a blue sky

What does ‘solar panel power’ mean?

Solar panel power refers to the amount of solar energy a panel produces in Standard Test Conditions (STC).

All top-quality panels on the market are tested in a lab with a specific temperature (77°F), amount of sunlight (1000 watts per square metre), and air mass (AM1.5).

They are then given a power rating that’s expressed in watts (W).

Put enough solar panels together, and you’ll build a system with a power rating over 1,000 W, which is a kilowatt.

Every solar panel system produces an amount of kilowatt hours (kWh) per year, which is just a unit of measurement that explains how much energy your solar panels generate in the real world.

A system with a 4 kW power rating, for example, will produce 4,000 kWh of solar energy per year in an STC setting – but of course, reality is more variable.

Conditions for solar panels can therefore be better or worse than a lab setting.

So in Alaska, a 4 kW system will typically produce around 2,500 kWh per year, but in most areas of the contiguous US, that same collection of solar panels will generate 4,000-4,500 kWh.

And out west, in New Mexico, Arizona, and California, you can expect a 4 kW array to produce around 5,500-6,000 kWh.

And why is a solar panel’s power important?

A solar panel’s power is important because it directly affects the amount of free electricity you’ll receive from it.

A 400 W panel, for instance, will generate twice as much solar energy as a 200 W panel, allowing you to double your savings.

It’s practically impossible to change the other biggest factors behind the amount of solar energy you’ll produce – like the weather, your roof’s angle, and your house’s direction – so it’s best to focus on getting solar panels with a high power rating.

solar panels on a roof against a blue sky and palm trees

What’s the average power output of a solar panel?

Across the US, the average power output for a 400 W panel is 420 kWh.

It’s generally lower in the rest of the world, where the average power output of a 400 W solar panel is 400 kWh.

For comparison, the average American household’s annual electricity consumption is 10,632 kWh, according to the Energy Information Administration.

This is why you can’t power a household with just one solar panel, but instead require a system made of multiple panels.

So how many solar panels would you need to power a property?

The average home in the US would typically need 25 panels to cover its total electricity usage.

But the power output you’ll get from the same panel will be different in every town, city, and state, and can even differ between houses on the same street.

For more information, check out our full guide, How Many Solar Panels Do You Need?

What factors affect a solar panel’s power output?

The main factor affecting a solar panel’s power output is its power rating – and once you’ve decided on a panel, the biggest factors are the weather, the direction and angle of your roof, and whether your system is obstructed at all.

Ideally, you want your solar panels to absorb direct sunlight under clear skies, with no trees, clouds, or buildings in the way – though panels will still work when it’s cloudy or even snowy, just a bit less effectively.

Solar panels also work best if they’re south-facing, and angled between 25° and 55° – or in a perfect world, exactly 40°.

What’s the most powerful solar panel on the market?

The most powerful solar panel on the market is Jinko Solar’s Tiger Neo N-type 72HL4.

It has a power rating of 575 W, which is around 50% more powerful than the average panel.

Originally from China, Jinko Solar produces solar panels in Jacksonville, Florida, as well as locations in Malaysia, Vietnam, and China.


You now have all the information you need to know about solar panels’ power ratings.

The more powerful the solar panel, the fewer you’ll need to produce the same amount of electricity – but you might end up paying more.

If you take different panels’ power into account when deciding between quotes, as well as their efficiency ratings, you should be well-positioned to make the right choice for your home.

Back to Top