Televisions have a reputation for costing a lot to run, and it is largely inherited from an earlier generation of sets.
Modern panels use considerably less power than plasma screens or cathode ray tube televisions did, and for most households the figure is smaller than expected. It is not nothing, and there are a few things that move it more than others.
Working out your own figure
The arithmetic is simple enough to do in a minute.
Find the power consumption in watts, which appears on the energy label, in the manual, or on a sticker on the back of the set. Divide by 1,000 to get kilowatts. Multiply by the hours you watch per day. Multiply by your electricity rate per kilowatt hour.
So a set drawing 100 watts, watched four hours a day, uses 0.4 kilowatt hours daily. At a rate of 25p that is 10p a day, or a little under £37 a year.
For most households the annual cost sits somewhere between £15 and £60, depending on screen size, how much it is on, and what rate you pay.
What actually drives the number
Screen size is the biggest factor, and it is not proportional. A larger panel has more area to illuminate, so consumption rises faster than the diagonal measurement suggests.
Brightness is the second, and it is the one you control. The backlight setting has a direct relationship with power draw, and shop-floor picture modes run it high. A set left in a display mode uses noticeably more than the same set set up for a living room.
Panel type matters too. Different technologies produce light in different ways and draw different amounts to reach the same brightness.
Content has a smaller effect than people assume on most sets, though on panels that dim locally, a dark film genuinely uses less than a bright one.
Standby is smaller than its reputation
Standby consumption used to be a real cost. Regulations have brought it down substantially, and most modern sets draw a very small amount when off.
Over a year that adds up to a fairly trivial figure. Switching off at the wall saves it, at the cost of the set taking longer to start and losing any scheduled updates.
The exception is a set with quick start or fast wake enabled, which keeps more of the system powered to reduce start-up time. If that is on and the set is rarely used, turning it off is worth doing.
Reading the energy label
UK energy labels show a rating from A to G along with consumption figures in kilowatt hours per 1,000 hours of viewing.
That per-1,000-hours figure is the useful one for comparison, since it lets you compare two sets directly without doing any conversion. Roughly speaking, 1,000 hours is around three hours a day for a year.
Labels also show separate figures for SDR and HDR content, and the HDR figure is higher because the panel runs brighter.
Settings that reduce it without spoiling the picture
A few changes cut consumption and generally improve the picture at the same time.
Drop the backlight to suit the room. A set at maximum brightness in an evening living room is both uncomfortable to watch and drawing more than it needs. This is the single largest saving available.
Move out of the shop-floor picture mode. Movie or Cinema modes run the panel lower and look more accurate. There is more on this in the note on picture settings worth changing.
Use eco or energy saving mode if the set has one, then check you are happy with how it looks. Some implementations are subtle, others less so.
Turn on the ambient light sensor if the brightness shifts do not bother you, since it drops the backlight automatically in darker rooms.
Use the sleep timer if the set regularly stays on after everyone has stopped watching, which is a surprisingly common source of hours.
Size and the running cost trade-off
Worth factoring in when choosing a screen size.
A larger set costs more to run every year it is in use, so the difference between two sizes is not only the purchase price. Over a decade the gap is real, though rarely large enough to be the deciding factor on its own.
For a bedroom, kitchen or a caravan, a smaller set makes sense on several grounds and running cost is one of them. There is more on choosing for smaller rooms in the 32 inch TV guide.
Keeping it in proportion
Set against a household electricity bill, a television is a modest item. Heating, hot water and cooking sit well above it.
That said, the backlight adjustment costs nothing, takes a minute, reduces the figure, and makes the picture better. There are not many changes that do all three.
You can browse the range at Cello Electronics, where energy information is listed against each model.