Sunday, October 12th, 2008
Defanging your Entertainment Center’s Vampire
A lot of people enjoy watching TV and movies at home. My family really does. Most folks have some variation of entertainment system setup at home. Some basic components that almost every entertainment system include are TV, DVD Player and/or VCR and cable box. Some larger entertainment systems include a stereo receiver, CD player, DVR (e.g. TiVo), MP3 player and more. What most people don’t realize is that each of these components draws power even when turned off and it can be a considerable amount when you combine all the components in your entertainment center.
Why do they draw power even when they are turned off? A common reason is so that you can use the remote control to turn them on.
A good device/component, in my opinion, is one that uses the least power when turned off. In the entertainment center world good is under 2W when off. Bad can be >90W (WHEN TURNED OFF) and even 20W over time adds up very quickly. With a few minutes and a power strip, I have been able to lower the vampiric load of my entertainment center by 40W, read on to find out how you can do the same and what this will save you over time.
Steps to reduce the bite from your entertainment center:
- Inventory the components in your entertainment center. Identify which components you want to be able to turn on from the comfort of your couch (e.g., it is really nice to turn the TV on using the remote from the couch). Identify those components that you have to stand up to use already (e.g. you need to get up to put in a VCR tape or DVD). If you have a watt meter handy, (e.g. kill-a-watt) measure and record how much power each component uses when turned off so you can determine if it is worth it or not.
- Plug those components, like the DVD player, that you already need to stand up to use into a power strip. I am a big fan of saving energy without sacrificing quality of life and convenience first. Once you’ve done all those things, then you can make harder decisions about sacrificing convenience to save the world.
- Consider the remaining components. Are there any that you can live with needing to stand up to use? My favorite one to recommend is your cable box. A cable box can use between 20-30W when turned off. The fancier the cable box, such as digital and/or HD, the more power it uses even when turned off. Who needs to use their cable box when their TV is turned off. My cable box uses 29W when powered off. We rarely watch TV directly through the cable box, so that was a no brainer for me. Be careful with Digital Video Recorders (DVR), e.g., TiVo, because they need to be on to record the shows and they may be using the cable or satellite box to get their signal. Also, some cable boxes have DVRs built into them, in which case if you want them to work, they need to stay powered up.
- Turn off the powerstrip. When you want to use your VCR, turn it on from the power strip, insert the tape and enjoy.
- (Optional) Calculate your savings. I’ll go into showing how to calculate your savings below. For a few minutes of my time, I will be able to save 30 kWh a month or about $5.
Calculating Savings
- Take the sum of the power savings from turning off those components, in my case that is 40W for the cable box (29W), DVD Player (2W) and VCR (9W).
- Multiply that times 24 hrs/day to get the energy savings per day (Wh)
- Multiply by 30 days/month to get monthly savings
- Or multiply by 365 days/year to get annual savings
- Divide by 1,000 to get the answer in kWh (the same thing you pay the electric company based on)
- Multiply your energy savings by your electric rate (e.g., $0.17/kWh) to get monetary savings.
- Multiply your energy savings by 1.341 lbs CO2/kWh which is the average US emissions of CO2 for electricity generation from a DoE Report in 2000 http://www.eia.doe.gov/cneaf/electricity/page/co2_report/co2emiss.pdf
My Example:
Monthly Savings
40W x 24hr/day x 30 days/month = 28,800 Wh per month
÷ 1,000 W/kW => 28.8 kWh per month
x 17¢/kWh => $4.90 per month
x 1.341 lbs CO2/kWh => 38.6 lbs CO2 per month
Annual Savings
40W x 24hr/day x 365 days/year ÷ 1,000 W/kW = 350.4 kWh per year
x 17¢/kWh => $59.57 per year
x 1.341 lbs CO2/kWh => 470 lbs CO2 per year
There are also sensing power strips out there that will turn off auxiliary devices when a main device is in standby mode. For example the printer for a computer or your cable box, VCR and DVD Player for your TV. I’ve not used one of these before, but they sound like they would be a nice marriage between convenience and saving energy.
