What Is a Megawatt-Hour (MWh)? Solar Output Explained

Quick answer

Megawatt-Hour A megawatt-hour (MWh) is a unit of energy equal to 1,000 kilowatt-hours. It is the energy made or used when one megawatt of power runs for one full hour.

Utilities, grid operators and the EIA count solar farm output, battery size, renewable energy certificates and wholesale power prices in MWh. A home uses roughly ten or eleven MWh in a year.

Quick facts

The key facts about megawatt-hour, with sources:

Equal to: 1,000 kWh, or 1 MW for 1 hour ¹
Average US home use, 2022: 10,791 kWh, about 10.8 MWh a year ²
One renewable energy certificate (REC): Issued per 1 MWh of renewable power delivered to the grid ⁸
US utility-scale solar output, Jan–Jul 2026: About 180.9 million MWh ³
Battery duration: Energy (MWh) ÷ power (MW) ⁶
US average home price, July 2026: 18.31¢/kWh, which is $183.10 per MWh ⁵

Key takeaways

One MWh is 1,000 kWh. It counts energy, the amount of electricity over time.
A typical US home uses about 10.8 MWh a year, per the EIA’s 2022 figure.
Solar farms sell output by the MWh. Wholesale prices and contracts are quoted in dollars per MWh.
A battery rated in MW and MWh can run for MWh ÷ MW hours at full power.
Each renewable energy certificate stands for one MWh of clean power.

An energy unit for big numbers

Energy is power used over time. The kilowatt-hour page explains the idea with a home bill. A megawatt-hour is the same thing, one thousand times larger.

Think of a megawatt as the size of the pipe. The megawatt-hour is the water that came out. A 1 MW solar farm at full sun for one hour makes 1 MWh. At half power for two hours it also makes 1 MWh.

Homeowners rarely see MWh on a bill. You meet it when you read about power plants, state energy reports, community solar contracts or big batteries. It also helps to turn a year of home use into one tidy number: about 10.8 MWh.

Sources: [1]

How MWh relates to the units around it

1 watt-hour (Wh) → a phone charger running for a few minutes
1,000 Wh = 1 kWh → the unit on your bill
1,000 kWh = 1 MWh → about five weeks of an average US home’s use
1,000 MWh = 1 gigawatt-hour (GWh) → a small solar farm’s output over a few months
1,000 GWh = 1 terawatt-hour (TWh) → the scale of state and national totals

How MWh are counted at a solar farm

A solar farm has a revenue meter where it connects to the grid. The meter adds up energy delivered, hour by hour. Those hourly MWh are what the owner gets paid for.

The EIA collects those totals from every plant of 1 MW or more. Its Electric Power Monthly table 1.17.B lists solar generation by state in thousand MWh. Through July 2026, US utility-scale solar made about 180.9 million MWh, up from about 148.0 million MWh in the same months of 2025.

How many MWh a farm makes per MW depends on its capacity factor. The capacity factor page covers that ratio. US solar plants ran at 24.4% in 2025, per EIA table 6.07.B.

Sources: [3] [4]

The kinds of MWh you will see

Same unit, different jobs.
Kind	What it counts	Where you see it
Generation (MWh)	Energy a plant delivered to the grid	EIA state tables, utility reports
Battery energy capacity (MWh)	How much a battery can store	Grid battery projects, next to a MW rating ⁶
Contracted energy (MWh)	Energy a buyer agrees to purchase	Power purchase agreements, community solar
Certificates (RECs)	The clean-energy claim for 1 MWh	Green power programs ⁸
Price ($/MWh)	What a MWh costs or earns	Wholesale markets, avoided cost rates

Example: turning MWh into things you know

All inputs are EIA or EPA figures. The rest is arithmetic.

Question	Math	Answer
How long does 1 MWh last an average home?	1,000 kWh ÷ (10,791 kWh ÷ 365 days) ²	About 34 days
What is the US average home price per MWh?	18.31¢/kWh × 1,000 ⁵	$183.10 per MWh (July 2026)
South Carolina home price per MWh?	15.47¢/kWh × 1,000 ⁵	$154.70 per MWh (July 2026)
How long can a 6 MW, 24 MWh battery run?	24 MWh ÷ 6 MW ⁶	4 hours at full power
How many RECs does 2,000 MWh of solar earn?	2,000 ÷ 1 ⁸	2,000 RECs

The retail price per MWh includes delivery, poles and wires. It is not what a solar farm earns per MWh, which is usually set by a contract or a market.

MWh compared with related terms

Linked terms have their own pages.
Term	Type of unit	Size	Typical use
Kilowatt-hour (kWh)	Energy	1/1,000 MWh	Your bill, your system’s yearly output
Megawatt-hour (MWh)	Energy	1,000 kWh	Farms, RECs, wholesale prices, big batteries
Megawatt (MW)	Power	Rate, not amount	Solar farm size
Battery capacity	Energy	kWh at home, MWh on the grid	How long a battery lasts
Solar production	Energy over a period	Any energy unit	Estimates and monitoring

Where MWh show up for a homeowner

Community solar. A plan may list a farm’s yearly output in MWh and your share as a percent. Multiply to get your kWh, then compare it with your use. Our community vs rooftop guide walks through it.

Utility filings. Rate cases and resource plans state energy in MWh or GWh. Export credit rates are sometimes set from avoided cost stated per MWh. Divide by 1,000 to compare with your bill in kWh.

State statistics. Reports on how much solar a state makes use MWh. Our rooftop solar by state study uses the same EIA data.

Why the MWh is a useful unit, and where it trips people

Useful for

Comparing the output of plants of different sizes on the same scale.
Turning cents per kWh into dollars per MWh for big contracts.
Seeing how long a grid battery lasts, when paired with its MW rating.
Counting clean energy claims, one REC per MWh.

Watch out for

Mixing MWh with MW in the same sentence.
Comparing a retail price per MWh with a wholesale one.
Forgetting that a yearly MWh total hides when the power arrived.
Assuming a home share of a MWh total equals a bill credit of the same size.

What a MWh total leaves out

A year of MWh is a sum. It does not show the timing. Solar MWh bunch up at midday and in summer. In January 2026 US solar plants ran at 15.7% capacity factor and in July 2026 at 32.4%, so a month in winter can make half as much as a month in summer.

Timing changes value. A MWh at 6 pm on a hot day is worth more to the grid than one at noon in spring. That is why some utilities pay different export rates by time of day. The time-of-use guide explains it for homes.

Sources: [4]

Prices per MWh and what drives them

Retail electricity is priced per kWh, but you can restate it per MWh. EIA table 5.6.A puts the US average home price at 18.31¢/kWh for July 2026, which is $183.10 per MWh. A year earlier it was 17.45¢.

What a solar farm earns per MWh is a different number. It is set by a contract or a wholesale market and is not public for most projects, so we do not give one. Drivers include time of day, location on the grid and the length of the contract.

The levelized cost of a MWh is a way to compare plants over their life. See levelized cost of energy. For a home, use our solar cost guide instead.

Sources: [5]

How a MWh moves from a farm to a bill

Panels make DC power. Inverters turn it into AC.
The farm’s meter records the MWh sent to the grid each hour.
The grid operator or utility settles payment for those MWh under the contract or market rules.
If the farm is renewable, one REC is issued per MWh and tracked in a registry ⁸.
The energy blends into the grid. Your meter counts the kWh your home draws.
Your utility bills you per kWh at its approved rate.

Tracking MWh over time

Farm owners compare actual MWh with expected MWh every month. A shortfall points to broken strings, dirty panels, tripped inverters or shading from new growth.

A home can do the same at a smaller scale. Add up your monitoring app’s kWh for the year and divide by 1,000. If it falls well short of the proposal’s estimate, read our underproduction guide or ask for solar repair.

Warning signs in MWh claims

A battery described only in MW, with no MWh. You cannot tell how long it runs.
A community solar offer with a farm’s MWh but no estimate of your own kWh.
A REC sold twice, or a green claim with no REC behind it ⁸.
A savings pitch that multiplies MWh by the retail price when you are paid a lower export rate.
Year-to-date totals compared with full-year totals.

Quick check

To compare any MWh figure with your own bill, divide it by 1,000 and read it as kWh.

Who counts and regulates MWh

Reporting. The US Energy Information Administration surveys plants of 1 MW or more each month on Form EIA-860M and publishes generation in its Electric Power Monthly.

Green claims. The US EPA says RECs are issued when one MWh of renewable electricity is generated and delivered to the grid. It calls them the instrument buyers must use to back a renewable use claim on a shared grid.

Prices. State utility commissions approve retail rates per kWh. Wholesale MWh prices are set by markets or contracts under state and federal oversight. Ask your utility which tariff sets your export credit.

Sources: [7] [8]

Common mix-ups

Myth A 100 MWh battery can supply 100 MW.: Reality Not necessarily. Power (MW) and energy (MWh) are separate ratings. Duration is MWh ÷ MW ⁶.
Myth A REC is electricity.: Reality A REC is the claim to the clean attributes of 1 MWh, tracked separately from the power itself ⁸.
Myth Retail price per MWh is what solar farms get paid.: Reality Retail includes delivery costs. Farm revenue is set by contract or market.
Myth MWh and MW/h mean the same.: Reality MWh is megawatts times hours. "MW per hour" is a rate of change, a different thing.

Solar MWh in SC, GA and VA

EIA table 1.17.B shows utility-scale solar generation through July 2026 of about 2,431 thousand MWh in South Carolina (2,047 a year earlier), 6,716 thousand MWh in Georgia (6,649) and 4,400 thousand MWh in Virginia (3,890) ³.

July 2026 home prices were 15.47¢/kWh in SC, 16.27¢ in Georgia and 17.55¢ in Virginia, or $154.70, $162.70 and $175.50 per MWh ⁵.

When the MWh matters to you

You are reading a community solar or green power offer.
You want to compare your home’s yearly use with a farm or a battery.
You are checking a news claim about how much a project will produce.
You buy power for a business and see prices in $/MWh.

Next steps

Community solar finderSee shared solar options
Solar savings calculatorYour bill in kWh terms
Battery sizing toolMatch kWh of storage to your needs

Questions about megawatt-hour

How many kWh are in a MWh?

There are 1,000 kilowatt-hours in one megawatt-hour. To turn MWh into kWh, multiply by 1,000. To go the other way, divide kWh by 1,000. A home that used 10,791 kWh in a year, the EIA’s 2022 US average, used about 10.8 MWh.

How many homes does 1 MWh power?

One MWh covers an average US home for about 34 days. The EIA puts average home use at 10,791 kWh a year in 2022, or about 30 kWh a day. So 1 MWh could also cover about 34 homes for one day. Homes in hot or cold states use more.

What is the difference between MW and MWh?

MW is power, how fast energy flows. MWh is energy, how much flowed. A plant’s size is in MW. What it made is in MWh. One MW running for one hour makes one MWh. Batteries list both, and the ratio gives hours of run time.

How much does a MWh of electricity cost?

At retail, the US home average was $183.10 per MWh in July 2026, from EIA’s 18.31¢ per kWh. South Carolina was $154.70. Wholesale and contract prices for solar farms are lower and vary by market and contract, and most are not public.

How many MWh does a 1 MW solar farm produce in a year?

About 2,100 MWh at the US average. The EIA reports a 2025 capacity factor of 24.4% for utility-scale solar. One MW times 8,760 hours times 0.244 is about 2,137 MWh. Sunny sites with trackers make more, and northern fixed-tilt sites make less.

What does battery MWh mean?

It is how much energy the battery can store. Its MW rating is how fast it can deliver. The EIA divides MWh by MW to get duration in hours. As of 2020, the EIA said US grid batteries could run at full power for about 3 hours on average.

What is a REC and how does it relate to a MWh?

A renewable energy certificate is issued for each MWh of renewable power delivered to the grid, according to the EPA. It holds the clean-energy claim for that MWh. Whoever owns the REC can claim the renewable use. It cannot be claimed twice.

How do I convert cents per kWh to dollars per MWh?

Multiply cents per kWh by 10. For example, 15.47 cents per kWh equals $154.70 per MWh. That works because a MWh is 1,000 kWh and a dollar is 100 cents. Use this to compare your bill rate with prices in utility filings.

How much solar energy does South Carolina produce?

Utility-scale solar in South Carolina made about 2.43 million MWh from January through July 2026, per EIA table 1.17.B. That was up from about 2.05 million MWh in the same months of 2025. Rooftop output is counted separately as small-scale solar.

Sources

US EIA, Electricity explained: Measuring electricity, retrieved October 8, 2026.
US EIA, FAQ: How much electricity does an American home use? (2022 data), retrieved October 8, 2026.
US EIA, Electric Power Monthly Table 1.17.B, Net generation from solar PV by state, year to date through July 2026, retrieved October 8, 2026.
US EIA, Electric Power Monthly Table 6.07.B, Capacity factors for utility-scale non-fossil generators, retrieved October 8, 2026.
US EIA, Electric Power Monthly Table 5.6.A, Average price to ultimate customers by state, July 2026, retrieved October 8, 2026.
US EIA, Today in Energy: Duration of utility-scale batteries depends on how they’re used (25 Mar 2022), retrieved October 8, 2026.
US EIA, Form EIA-860M Preliminary Monthly Electric Generator Inventory, retrieved October 8, 2026.
US EPA, Green Power Markets: Renewable Energy Certificates (RECs), retrieved October 8, 2026.

Expert review

Written by the HyreSolar Research team. Not yet reviewed by an outside expert. We say so rather than imply a review that has not happened; see our editorial policy.

How the numbers were checked: Units from the EIA. Generation, prices and capacity factors from EIA Electric Power Monthly tables 1.17.B, 5.6.A and 6.07.B (July 2026 data); battery duration from EIA Today in Energy; REC definition from the EPA. Worked examples are arithmetic on those figures. No equipment or contract price is given (G-COST).

Suggest a correction. We fix errors and say what changed.