In short
- According to Argentina’s official table (ENRE), a 24" LED TV uses about 40 W and a 32" to 50" one about 90 W. A 29" to 34" tube (CRT) TV, about 175 W.
- At 5 hours a day, the 32" to 50" LED comes to 13.5 kWh a month; the tube TV, about 26.
- Replacing the tube TV with an LED saves about 12.8 kWh a month at those hours.
- ENERGY STAR certified TVs use on average 34% less, and 0.5 W or less in standby.
Words you’ll see
- Watt (W): power at any moment. kWh: energy over time; it’s what your bill charges for. More in watts, kWh, volts and amps.
- Inches ("): screen size, measured diagonally.
- Standby power: what it uses when switched off with the remote, with the little light on.
- Automatic Brightness Control: a sensor that dims the screen when the room is dark.
How many watts does a TV use?
| TV | ENRE (Argentina) |
|---|---|
| 24" LED | 40 W |
| 32" to 50" LED | 90 W |
| 40" LED (another row) | 180 W |
| 21" tube | 75 W |
| 25" tube | 155 W |
| 29" to 34" tube | 175 W |
Notice that the same table gives two figures for a 40" LED: 90 W in the 32"-to-50" row and 180 W in another. It isn’t our mistake: two TVs of the same size can use very different amounts depending on the model and brightness. So for yours, check its label. The older U.S. Department of Energy table reproduced by Virginia Tech gives 65 to 133 W for 19" to 36" color TVs and 120 W for a flat screen.
How much does it use per month?
Watts × hours a day × 30 days. At 5 hours a day:
- 24" LED: 40 × 5 × 30 = 6 kWh.
- 32" to 50" LED: 90 × 5 × 30 = 13.5 kWh.
- 29" to 34" tube: 175 × 5 × 30 = 26.25 kWh.
That’s what the electricity usage calculator gives for those TVs at 5 hours. Enter your own hours.
Where to find your TV’s figure
- On the label on the back (watts, or volts and amps) or in the manual.
- On the energy label, if your country uses one: it gives kWh per year or watts in use. See how to read an energy label.
- With a plug-in energy meter, which also tells you its standby use.
Worked example: replacing a tube TV with an LED
- 29" tube TV: 175 W. 32" to 50" LED: 90 W.
- Difference: 175 − 90 = 85 W.
- At 5 hours a day for a month: 85 × 5 × 30 = 12,750 Wh, about 12.8 kWh.
- At an example price of $0.15 per kWh (use the one on your bill): about $1.91 a month, about $23 a year.
And the LED gives you a bigger screen for about half the power.
Settings that bring it down
According to ENERGY STAR (the U.S. government’s efficiency program):
- Automatic Brightness Control saves energy and improves the picture: it matches the screen to the room’s light.
- Local dimming (switching off or dimming sections of the backlight) saves energy and gives deeper blacks.
- TVs ship with pre-set picture modes: use the one carrying the ENERGY STAR mark to make sure you save.
- Certified TVs use on average 34% less energy than conventional models and 0.5 W or less in standby.
Common mistakes
- Going by screen size alone. The official table itself gives 90 and 180 W for a 40" LED: check your TV’s label.
- Leaving everything around it always on. The set-top box, console or sound system keep drawing power in standby; see standby power.
In power outages and storms
A 90 W LED TV is easy to keep running on a battery: work out how many hours with the power outage battery calculator. To protect it from power surges, read how to protect your appliances. If the outlet or power strip gets hot, have an electrician check it.
Sources and references
- Ente Nacional Regulador del Gas y la Electricidad (Argentina). Consumo básico de electrodomésticos (24", 32"–50" and 40" LED TVs; 21", 25" and 29"–34" tube TVs).
- Grisso, R., Walker, M. and Ignosh, J., Virginia Cooperative Extension (Virginia Tech), 2020. Estimating Appliance and Home Electronic Energy Use (Department of Energy table: 19" to 36" color TVs, 65–133 W; flat screen, 120 W).
- ENERGY STAR (EPA and U.S. Department of Energy). Televisions (34% more efficient on average; 0.5 W or less in sleep mode; Automatic Brightness Control, local dimming and ENERGY STAR picture settings).
Frequently asked questions
How many watts does an LED TV use?
According to Argentina’s ENRE table, a 24" model uses about 40 W and a 32" to 50" one about 90 W. The same table lists 180 W for a 40" LED in another row: it depends on the model, so check your TV’s label.
How much electricity does a TV use per month?
A 32" to 50" LED at 5 hours a day: 90 × 5 × 30 = 13.5 kWh a month. A 29" tube TV: 175 × 5 × 30 = 26.25 kWh.
How much does a TV use in standby?
ENERGY STAR certified TVs use 0.5 W or less in standby. Others can use more; a plug-in meter will tell you.
