How Much Electricity Does an Apartment Use per Day?

How much electricity does an apartment use per day? About 16.7 kWh a day in a building with 5 or more units and about 18.2 kWh a day in a building with 2 to 4 units, by my math from the EIA’s 2020 survey. Region matters more than building size: a large-building apartment averages about 12.8 kWh a day in the Northeast and 22.1 kWh in the South.

By my math, that’s roughly 60% of what an average US home uses.

How much electricity does an apartment use per day by building size?

Apartment electricity use per day averages 16.7 kWh in buildings with 5 or more units and 18.2 kWh in buildings with 2 to 4 units. Both are well under the 29.0 kWh a day the average US home uses.

These numbers come from the EIA’s Residential Energy Consumption Survey 2020, Table CE2.1. The EIA reports them in million Btu per household. I converted them using the EIA’s figure of 1 kWh = 3,412 Btu.

Home type (RECS 2020)	Million Btu a year	kWh a year	kWh a day	kWh a month
Apartment, 5+ unit building	20.8	6,096	16.7	508
Apartment, 2-4 unit building	22.7	6,653	18.2	554
All US homes	36.1	10,580	29.0	882

By my math, the kWh columns are the Btu figure x 1,000,000 / 3,412, then / 365 or / 12. Rented apartments in general land at 17.1 kWh a day.

Smaller buildings use a bit more per apartment, though the survey doesn’t say why. The EIA’s separate FAQ on home use gives 10,791 kWh a year, about 899 kWh a month, for the average residential customer in 2022.

Apartment electricity use by region

Region changes daily apartment use more than building size does, because heating and cooling depend on climate. In the South, apartments in large buildings average about 22.1 kWh a day; in the Northeast, about 12.8 kWh.

By my math from the RECS regional tables for the Northeast, Midwest, South and West:

Census region	2-4 unit building, kWh a day	5+ unit building, kWh a day
Northeast	15.5	12.8
Midwest	17.4	15.2
South	24.9	22.1
West	15.5	14.0

The South stands out because it runs more air conditioning and more electric heat. In the Northeast, many buildings heat with gas or oil, so that energy never shows up as kWh. The national table shows the same pattern: apartments in 2-4 unit buildings burn twice as much natural gas as large-building ones (45.6 vs 22.8 million Btu).

Where an apartment’s electricity goes

An apartment’s electricity goes mostly to water heating, air conditioning and space heating, plus a large mix of lighting, electronics and appliances. In large buildings, those three climate and hot-water uses take about 48% of the total.

By my math from RECS Table CE4.1, divided across all apartments of each type:

End use	5+ units, kWh a day	Share	2-4 units, kWh a day	Share
Space heating	2.1	12.8%	2.6	14.2%
Water heating	3.1	18.7%	2.9	16.0%
Air conditioning	2.7	16.4%	3.2	17.5%
Refrigerators	1.5	8.8%	1.6	8.5%
Everything else	7.2	43.2%	8.0	43.9%

“Everything else” covers lighting, TVs, cooking, laundry and plug-in gear. The detailed tables (CE5.1a and CE5.1b) put lighting at about 1.2 kWh a day and TVs at about 1.1 kWh in large-building apartments.

These are averages over every apartment, including ones that heat with gas. If your heat and hot water are electric, your share for those rows is much higher.

The always-on load

The always-on load is the power your home draws all day even when you aren’t using anything: the fridge, router, chargers and standby devices. An NRDC study of 70,000 California homes measured an average of 164 watts, nearly 23% of their electricity use.

By my math, 164 W x 24 hours is about 3.9 kWh a day, or about 24% of a large-building apartment’s 16.7 kWh. It matters for solar because it runs while the sun is up whether you’re home or not.

Daytime vs evening electricity use

Most apartment electricity is used in the morning and evening, when people are home, while daytime use is closer to the always-on load. The EIA notes that home electricity use “follows the daily habits of its residents.”

The EIA’s hourly data shows the grid-wide pattern:

Lowest demand: around 5:00 a.m., when most people sleep.
Summer: one peak, around 5:00 p.m. or 6:00 p.m., driven by air conditioning.
Winter: a morning peak and an evening peak.

For a renter who works away from home, that means midday use sits near the 164 W floor: the fridge cycling, the router, a few devices on standby. Cooking, laundry, TV and lighting pile into the evening, after the sun has dropped. If you work from home, your daytime load is higher.

How to find your own daily kWh

You can find your own daily kWh by dividing the kWh on your bill by the days in the billing period, or by downloading your smart-meter data. The bill gives an average; the meter data shows the hour-by-hour shape.

From your bill. Find “kWh used” and the number of days billed. Say your bill shows 540 kWh over 30 days: that’s 18 kWh a day.
Through your utility account. Look for a Green Button “Download My Data” link. The Department of Energy says it lets you download your own usage data to your computer in a common XML format. Over 50 utilities and electricity suppliers have signed on.
For single devices. DOE’s Energy Saver formula (Wayback Machine copy) is wattage x hours used per day / 1000 = daily kWh. A plug-in usage monitor measures the real draw.

What to look for in the hourly data: your lowest overnight hour is roughly your always-on load. Your midday hours on a workday show what a solar kit could offset.

An 800 W balcony kit can cover roughly 2 to 3 kWh a day of an apartment’s use, depending on how it’s mounted. Against an average apartment, that’s about 9% to 18% of the power you use, and less of the power you actually save on.

Our kit-size guide modeled an 800 W kit on a Baltimore balcony with PVGIS hourly data. By my math from its results:

Output: 737 kWh a year hung vertically on the railing is about 2.0 kWh a day. Tilted at 35 degrees, 1,103 kWh is about 3.0 kWh a day.
Used at home: with a steady 164 W load, 423 kWh a year, or about 1.2 kWh a day, replaces grid power. Tilted, it’s 506 kWh, about 1.4 kWh a day.

The real example. Baltimore is in the South census region, where a large-building apartment uses about 8,060 kWh a year. A vertical 800 W kit makes about 9% of that, and the self-used part covers about 5%. Against the national large-building average of 6,096 kWh, the shares are about 12% and 7%.

The rest of the output flows out through your meter. Our post on extra power from balcony solar explains why that usually earns nothing.

My take: your total kWh per day matters much less than your daytime kWh. A Southern apartment using 22.1 kWh a day, mostly in the evening, can waste as much solar output as a Northeastern one using 12.8 kWh. I’d download a week of hourly data before buying anything, and size the kit to the midday floor, not the bill total.

To test your own numbers, our balcony solar calculator takes your kit size, sun hours, price and the share you use at home. It runs above PVGIS results by 9-16%, so read it as an upper estimate. For whether the savings justify the price, see are balcony solar panels worth it and the balcony solar cost guide.

Limits of these numbers

These figures are 2020 survey averages, so they describe a typical apartment, not yours, and they miss any change in habits since then.

The RECS totals also include power from on-site solar panels, and the averages mix electric-heat and gas-heat homes. The NRDC’s 164 W comes from California homes in 2015, and the balcony shares rest on one city’s sun. Your own bill and meter data beat every average here.

FAQ

Is using 20 kWh a day too much for an apartment?

It’s above the national apartment average but normal in some places. By my math from EIA’s 2020 survey, apartments in buildings with 5 or more units use about 16.7 kWh a day nationally, but about 22.1 kWh a day in the South, where air conditioning and electric heat are common.

Is 500 kWh a month a lot for an apartment?

No, 500 kWh a month is about average. By my math, EIA’s 2020 figures work out to about 508 kWh a month for apartments in 5+ unit buildings and 554 kWh for 2-4 unit buildings. A whole US home averaged about 899 kWh a month in 2022.

What uses the most electricity in an apartment?

Water heating, air conditioning and space heating are the biggest single uses, together about 48% of electricity in large apartment buildings by my math from EIA data. The largest block, about 43%, is everything else: lighting, TVs, cooking, laundry and plug-in devices.

How much electricity does a 900 sq ft apartment use?

EIA doesn’t publish apartment figures by exact size, so treat the building-type average as your benchmark: about 17 to 18 kWh a day by my math. Your bill is the better answer: divide the kWh used by the days in the billing period.