HomeExplainedHow much power a charger draws when nothing is plugged in
How much power a charger draws when nothing is plugged in
The median Level 2 charger on the ENERGY STAR certified list draws 3.66 W with no car connected. Left in that state for a whole year, that is about 32 kWh. The 424 Level 2 listings run from 0.72 W to 14.57 W.
A wall charger spends most of its life waiting. It is powered, its electronics are on, its radio may be connected to a router or a cell network, and no car is attached. ENERGY STAR calls this no-vehicle mode and records the input power for every certified model. This site calls it standby draw. It is the one test value that applies to every hour a charger is not in use.
How the 424 Level 2 listings spread out
Half of the listings draw between 2.81 W and 5.55 W. Only 52 stay under 2 W, and 17 go above 8 W. The shape is lopsided: a dense block between about 2 and 6 W, then a thin tail that runs out to almost 15 W. The highest Level 2 listing draws about twenty times as much as the lowest.
The five lowest are the Topband TB-AC240US (0.72 W), Pando Electric Pando 001 Smart Outlet (0.75 W), Grizzl-E Classic (0.8 W), EVFastCharge / MOTEN EVFC MTL-AC-EV48 (0.83 W) and Lectron LECHG14-50-40ABLKUS (0.83 W). The five highest are the REALSEE CNAC-06 (14.57 W, 160 A), ChargePoint CP6000 Single Port (14.565 W, 80 A), Blink Series 8 (11.7 W, 80 A), Elinta Charge CityCharge V2 (11.58 W, 40 A) and Tellus Power TP-EVVA-NUL80ASS (11.56 W, 80 A).
The high end is dominated by large ratings: of the ten Level 2 listings with the highest standby draw, 5 are rated 80 A and 2 above 80 A. The ten lowest are spread over 3 ratings (40 A, 48 A and 50 A).
Outside Level 2, the lowest value on the whole list belongs to a dual-input unit, the Tesla 1937825, at 0.43 W.
Standby draw by amp rating
The 80 A listings have the highest median at rest and the 40 A listings the lowest. The 80 A group also carries more powered extras: 35 % list a high-resolution display, against 8 % at 40 A. The data cannot separate the two effects. Every rating still has listings under 2 W.
| Rating | Listings | Lowest, W | Median, W | Median, kWh a year* | Highest, W |
|---|---|---|---|---|---|
| 32 A | 25 | 1.61 | 3.4 | 29.8 | 6.33 |
| 40 A | 76 | 0.72 | 2.665 | 23.3 | 11.58 |
| 48 A | 134 | 0.83 | 3.54 | 31 | 10.91 |
| 50 A | 44 | 0.96 | 3.49 | 30.6 | 8.69 |
| 80 A | 112 | 1.51 | 5.535 | 48.5 | 14.565 |
* Median standby draw × 8,760 hours ÷ 1,000: the energy if the charger sat in standby for a full year. Medians are per listing.
Network connections and standby draw
The 368 networked Level 2 listings have a median standby draw of 3.78 W. The 56 without a network connection have a median of 2.93 W. The gap between the medians is smaller than the spread inside each group: 3 networked listings draw less than 1 W, which is below the non-networked median. The guide on networked chargers goes through the two groups in more detail.
By year of certification
Newer certifications do not draw less at rest on this list. Among years with at least 20 Level 2 listings, the median standby draw is highest for 2025 (4.68 W) and lowest for 2022 (3.43 W). The mix of ratings and features changes from year to year, so the table describes the list rather than a trend in any one kind of charger.
| Year certified | Listings | Median standby, W |
|---|---|---|
| 2020 | 10 | 3.48 |
| 2021 | 11 | 3.5 |
| 2022 | 49 | 3.43 |
| 2023 | 78 | 3.56 |
| 2024 | 119 | 3.87 |
| 2025 | 108 | 4.68 |
| 2026 | 45 | 3.9 |
Level 2 listings. Years with fewer than 10 listings are left out.
What a year in standby means
Watts are a rate; a year has 8,760 hours. At the Level 2 median of 3.66 W, a charger that never saw a car would use about 32 kWh in a year. The lowest Level 2 listing would use 6.3 kWh and the highest 127.6 kWh. These figures are upper bounds for illustration: a charger in daily use spends some hours charging or idle with a car attached, and those hours are counted under other test modes.
The site gives this figure as energy only. It does not convert it into a cost, because tariffs differ and the figure is not a measured use.
The allowance behind the number
ENERGY STAR does not set one standby limit for all chargers. Each listing has its own allowance for no-vehicle mode, and the listings with more features have higher allowances. The median Level 2 listing uses 64.65 % of its own allowance. A charger with a low draw in watts can still use a large share of a small allowance, so both figures appear on every charger page here. What the ENERGY STAR test measures covers the allowance in detail.
To see where any listing sits, open its amp-rating page, where all listings are sorted by standby draw. The charging-time tool covers the other side of the question: how long a charge takes once a car is plugged in.
Sources
- U.S. EPA, ENERGY STAR Certified Electric Vehicle Supply Equipment (AC-Output), data.energystar.gov, as of October 27, 2026.
- Computed figures are defined on how to read the data.