Hacker News Reader

Comment by wiz21c | Hacker News Reader

In the shop in my town, they sell televisions. Led ones, oled ones, big screen, the usual stuff. They have about 50 models. All have energy labels C or worse. No A, no A+, no B... Once there was an A one but the picture quality was horrible.

I'm happy to be more conscious, but someone is working against the scheme: I don't have a real choice...

View on HN

This is actually an example of the regulation working. The original energy labelling had done such a good job that every product was routinely getting A or up ratings. So the EU introduced a new system that was much more stringent, dropping everything down to a C at best but more usually an F. Gradually manufacturers are improving again.

“Working” assumes this new scale is actually based on reality and that an A or B is realistically obtainable without compromises (ie here image quality) that no one wants to make.

There's the law of conservation of energy. If you want a nice bright big screen there's no way around consuming a lot of electricity. If your baseline is a 32 inch LED screen it's not surprising a 65" OLED will have a worse energy label.

Seems most people want that nice TV more than a small, dim picture that uses less energy.

I don't think anyone says that a big TV should require the same energy as a paper sheet.

But if someone can manufacture a big TV with a third of the energy used for the average big TV, surely there is something that can be improved.

In addition to the laws of physics and the engineering required to build TVs working against this, the EU deliberately changed the energy efficiency scale for things like TVs a few years back to specifically make an A hard to get and something that wouldn't be achieved by products currently on the market. They were probably too optimistic about future improvements too - a lot of TVs had to add special eco modes that aren't really designed to be used to meet the minimum efficiency now required by EU rules.

How much TV does one have to watch to impact your energy bill? Does anyone care about it's energy usage?

Modern HDR blinding devices can go up to hundreds of watts.

All in the name of not having to place your TV in a shaded corner, and maybe acheiving a higher contrast ratio on paper.

What does it even mean for a TV to be energy efficient? A TV's job is to convert electricity into... light, I guess? It's not light like a light bulb, nor would you want it to be. You wouldn't light your home with TVs.

So is it something like "only produces light where needed on the screen" or "uses the least energy when turned off" or "does image processing for x format with the least energy" What are they measuring here?

Yes,measuring the energy consumption and efficiency of the conversion from electricity to light is part of the label. The light bulb example is not as unsuitable as you seem to assume. Incandescent light bulbs only convert about 5 percent of the energy consumed to light, the rest is converted to heat. LEDs, in contrast, are 6 to 8 times more efficient.

Your "does image processing..." part is also important. Different processors consume vastly different amounts of energy. A hobbyist example would be trying to run something on a battery powered ESP32 with or without deep sleep.

I meant it's it's physics job to produce light. If it does that efficiently, great! That's one thing you should want.

It's human job is to convey information. If you're measuring efficiency that way, it would be most efficient to have the dimmest screen possible (using the least energy) as long as you can still tell what's happening on screen. If that's already happening, then surely a screen twice as bright as you need it to be would use twice the energy and be half as efficient, even if it physically is equally as efficient making light at any brightness.

You could be using half the energy to do the "same" job.

You can check the label here https://energy-efficient-products.ec.europa.eu/product-list/....

It's the electricity usage when running the TV. There is e.g. quite a difference between LED and OLED.

TVs is also quite a large part of electricity usage in a household. Maybe 75 - 150W running a few hours a day. You have to keep in mind that not many people have PCs, NAS, etc. running 24/7.

Reply on news.ycombinator.com