Sunday, April 20, 2008

If GE is so Green, Why Do They Put a Clock on Everything?

VAMPIRE POWER! Sounds scary huh? Well it is. "Vampire power" is a term used to describe electronics' continued energy use when in a powered-off state, also referred to as standby mode. Even though you may have taken your phone off the charger or hit the "off" button on your TV, those devices are likely continuing to draw a trickle of power that can add up over time on your electricity bill and carbon footprint.

As an example, here's a back-of-the-napkin type calculation. There are around 230million cell phone users in the US. If 10% of them leave their charger plugged in all the time, charges their phone 1hr/day, and the charger uses about 0.1W (see pg 87) when not in use, this adds up to over 19 million kWh of wasted electricity. If half that is from coal (~1 metric ton of CO2/MWh) and 15% from natural gas (~.5 tCO2/MWh), we're talking about roughly 15,500 tCO2 from wasted energy in cell phone chargers, and I think that I'm being conservative here. Now think about your microwave, TV, computer, etc. You get the idea.

Now before we get too worked up, standby power can be useful for features such as memory retention in your DVR or computer or to allow use of a remote control to turn devices on and off. However, I don't understand why charging devices should draw power when not in use (can a EE explain this to me?), and I personally see absolutely no reason why every kitchen appliance needs to have a clock, hence the title of this post. I've seen a coffee maker that uses an LCD display to show a digital image of an analog clock - this is absolutely ridiculous to me.

ENERGY STAR and the UK's Energy Savings Trust are fantastic market based mechanisms to give incentive to reduce standby energy consumption. The UK is even debating a ban on the standby option for electronics, though I am not sure this is reasonable.

What is reasonable, and necessary, is for consumers to change their behavior and product preferences regarding standby power use. If you had to get up to turn your TV on and off, would it be that big of a deal? You had to get up to walk to the couch anyway. If you wear a watch with a 3yr battery, do you really need 18 clocks in your kitchen? How about unplugging chargers when not in use (or plugging them all into a power strip that you can switch on and off)?

Behavior changes aren't always easy, but any move towards electricity conservation can help reduce CO2 emissions and your electricity bill. We don't need to wait on government programs and market economics to cut down on standby energy consumption, all we have to do is unplug.


charlotte said...

If you plugged everything into a power strip and turned it off, would it still be using power if it remains plugged in?

J.T. Marsh said...

I'm under the impression that turning a power strip off will stop the flow of electricity, but even if that's not the case, unplugging a power strip would be more convenient than unplugging several items separately. Apparently there are also "smart" power strips that turn off items if they are on standby for a long time.

Nick Flores said...

I have actually been thinking about this topic lately and the ways that I can implement it in my own life. Although I live with two other guys in my apartment, whenever I see an appliance plugged in, I try to unplug it because I found that even non-electronic objects can use power. Although I'm not a EE major, I believe one of the reasons is because electrical energy travels via the plug into the device to charge the capacitor in the object.

But I'm not sure that I understand all of what you have written. You wrote that the U.K. is considering a ban on standby options on all objects, but I think this could have some bad effects. For example, many objects much less energy during standby mode than they do while in active mode. Eliminating standby mode would simply leave two alternatives, either on or off completely. But what about objects such as computers? Standby options for computers seem to be very beneficial, because the hiberate function on a PC or laptop can be used to drastically reduce product energy use over the course of say, a lunch break, when compared to leaving the computer on and active.

I do agree that a coffee maker with an LCD seems a bit excessive, but I'm not sure that removing the timing function of some coffee makers is a good business idea. Many people enjoy a warm cup of coffee right when they wake up, and a coffee maker with a clock function enables this.

To be sure, if everybody turned off their power suddenly, we would see a decrease in the amount of energy used, but only at the expense of present way of life. We cannot sit at one extreme or the other, and people do not like to feel like they are regressing. Standby power in objects like computers enable the consumer to both reduce power consumption and resume their work in a quick fashion. It is these happy mediums that the electronics industry must seek.

J.T. Marsh said...

Nick, I completely agree that happy mediums are the way to go and that there are benefits to having a standby option (a couple examples are given in the third paragraph of my post). As I said, I don't really think that banning the standby option is reasonable, but it is interesting to me that such a measure is being considered.

Thanks for expounding on this topic. If I included all of the considerations you mentioned, my post would have been entirely too long!