The Green Lantern

Green Screen

Is it better for the environment to watch TV via satellite, cable, or the Internet?

What’s the greenest way to watch television?

Photo by Sean Gallup/Getty Images.

I just moved into a new apartment, and I can’t decide how to get my television fix. Would it be better for the environment if I watched via cable, satellite, or streaming over the Internet?

It’s high time to examine America’s favorite pastime. According to the Bureau of Labor Statistics, Americans spend 2.7 hours per day watching television. That’s half of our leisure time, and it would account for nearly six weeks per year of round-the-clock television watching.

All other things held equal, size matters: Your energy use will be higher if you’re watching TV on the flat-screen behemoth in your living room than it would if you were using the tiny display of your smartphone. So for the purposes of this comparison, let’s assume that no matter how the programming is delivered, you’re looking at it on the same type of screen.

From the consumer end of the equation, the outcome is very clear: Your set-top box, whether it’s hooked up to the cable system or a satellite provider, is a major waste of energy. You should get rid of it right now and switch to an Internet-based system that uses either a low-energy box or no box at all.

Over the course of a year, a set-top high-definition cable box paired with a DVR consumes 446 kilowatt-hours, which is 31 kilowatt-hours more than an Energy Star refrigerator, according to data (PDF) compiled by the Natural Resources Defense Council and Ecos Consulting. Almost two-thirds of that consumption occurs when you’re not even watching television, because the boxes use almost as much energy when not in use.

As for the differences between set-top boxes, the cable devices consume approximately 34 watts during use, which is slightly better than the satellite models. Hardware dedicated for streaming Internet content, such as the Apple TV or Roku box, tend to perform far better, using less than 7 watts during use. The Apple model consumes just 0.5 watts in sleep mode—a huge improvement over satellite and cable boxes.

An even better solution would be to video mirror downloaded programs from your laptop or other device using the appropriate adapter. The iPad, iPhone, and Android phones each use between 3 and 6 watts, far less than any of the standard set-top boxes. (A standard desktop computer isn’t a good alternative. Even when idle and with the screen off, they use more than 30 watts [PDF].) Your Wi-Fi router adds another 5 watts to the equation, and your cable or DSL modem might tack on another 4—although you’d probably be running those regardless.

The other end of the equation is the energy consumed by the satellite and cable companies sending the signal to your box. Unfortunately, there are no good data on their power consumption. The Lantern huddled with some consultants in this field who feel that the satellite providers probably beat out cable, if we’re looking only at television. Cable providers have to power and maintain thousands of infrastructure boxes on street corners around the country. They have to lay underground cable from house to house. And there’s a lot of embedded energy in those cables, such as the copper mining. Solar-powered satellites don’t share those problems.

On the other hand, most households receive broadband Internet, which shares a lot of the same infrastructure as cable. Some satellite providers even deliver video on demand through the Internet.

This lack of clarity isn’t particularly significant, however, because household energy consumption is what really matters. There are more than 112 million households in the United States, with an average of 2.24 televisions per home. Approximately 116 million of those 250 million televisions have set-top boxes, which means a collective, continuous energy consumption of approximately 4 billion watts. If they all switched to a video-mirrored tablet, it could save the energy grid as much as 2.6 billion watts. By comparison, the Internet giant Google shocked the world in September when the company revealed that, worldwide, its data centers continuously draw 260 million watts. Their total consumption is an order of magnitude less than the energy that could be saved nationwide if everyone turned off their set-top boxes.

That doesn’t mean the cable and satellite companies are off the hook. They could make a lot of changes to decrease energy consumption. First, they could choose less-energy-hungry set-top boxes, since consumers have no real choice in the matter. (European boxes, according to the NRDC report, are smarter with energy management.)

The home DVR model is also terribly inefficient. Most people record many times more programming than they ever intend to watch. And the recording system that allows you to rewind live television runs all the time, whether or not the TV is on. That means the DVR’s hard drive is spinning round-the-clock, eating through kilowatts.

It would be far more efficient to convert DVR to a video-on-demand-type system, with the television providers hosting the data remotely. That way many people could share the same copy of a show. Unfortunately, legal complexities have gotten in the way of this relatively obvious solution. Content providers say that arrangement would be more like pay-per-view than home DVRs, so they should get another payment each time a household watches their shows. Until the big boys can settle this, your electricity meter is going to keep spinning out of control.

The Lantern thanks Gregg Hardy of Ecos Consulting and Noah Horowitz of the NRDC.