Green Family Science: Pinpointing Constant Power Drain
Are there energy vampires in your house? There are probably more things sucking on your household energy than you realize! This summer, band together with your students to analyze your family's power usage—and to see what steps you can take to make a difference in your family energy usage footprint. From stereos to gaming systems to chargers for all of your devices, you might be surprised at how many things are plugged in—and how much energy each uses, even when it is just sitting around and waiting for your attention.
"When you aren't in the room, turn off the lights!"
"You all have to start turning off the lights!"
"It's sunny out, turn off the light."
"The lights are on in every room of the house again!"
"You don't need to turn every light in the bathroom on every time you walk in!"
Does the on and off of lights form a similar refrain in your house as you try and make your kids more aware of energy issues and trim corners on rising energy bills? The singsong of lights on and lights off is a buzz you will find in houses and buildings of all sizes. When we think of cutting down on the always-on energy, many people immediately think of lights. Have you been in an elementary or middle school and been surprised to find lights in classrooms off as the students work by daylight? Have you dutifully changed out light bulbs to more energy-efficient choices in hopes of saving an accumulation of pennies over time?
Lighting the Way
Attention to overhead and tabletop lighting may have some impact on your energy footprint at home, but the impact of your lights may be minimal in the context of the overall size of the print. Lights may be the most obvious culprit for a family's wasted electricity, but lights are likely only a drop in the energy bucket.
What else is running?
Some night when it is dark in the house, take a walk through the house and notice how many little lights you see, little green or orange or red or blue lights, signs that something is on, running, ticking, waiting for notifications, and otherwise sucking away at your power. Do you use a fancy single-cup coffee brewer that keeps water heated and ready to make an on-demand cup of coffee or hot chocolate? Do you use a digital video recorder to make sure you never miss a favorite show? These, and many other, devices and appliances draw some energy throughout the day, while they are sitting around and "waiting" for use. While many of the things plugged in may only use a trickle of energy when they are not actively being used by you, if you add up all the passive energy usage, you might be surprised! This kind of energy usage is sometimes called vampire or phantom power.
You may know when you glance at your computer that a blue light signals it is still on, and not in a suspended, hibernated, or "sleep" state even if it appears to be off. In another room, another computer may glow red for the same reason. Your gaming device may mean something different when the device light is red, green, or yellow. Devices and appliances with indicator lights are the ones you probably notice most often, but the lights you see probably only reflect a portion of the devices and appliances that are plugged in and possibly still running even when you are not using them.
Some devices give themselves away because they make more than their share of noise and/or because they kick in and out of activity, triggering lights and noise. The ever present hum of a digital video recorder or cable box, for example, may be a sound you notice when the house is quiet, a reminder that the TV is still active even when no one is watching. Gaming consoles, too, often whir in the background even when they are not being played. Even when flipped off, you may find that some devices seem to never "really" go off and may even kick back on when least expected, the disc insert slot lighting up at odd times as the system checks for and installs updates. It can be disconcerting when your kids are in bed, and suddenly the gaming system fires up and, with a whirring sound, starts spinning to life and drawing on the household power. But even the devices you don't think about, the subtle ones, may be hanging out waiting, and munching on a steady stream of energy.
How many devices have a digital clock face that is always on?
Summer Energy Investigation
With kids home for the summer, why not set up a student-led investigation into your family's power usage. With summer temperatures pushing some systems into cooling overdrive during summer months, energy bills may be on the rise, but with some detective work, some monitoring of energy usage, and some record keeping and basic applied math, you and your students can pinpoint engery-draining pitfalls and culprits—problems you may be able to tackle by changing how you and your family approach turning devices on and off.
Get the kids involved and see what a difference you can make!
The following Project Ideas offer a blueprint for carrying out specific kinds of energy usage analysis.
- Spare a Watt, Save a Lot: track how much energy your household appliances use—when they are actively in use and when they are not. Which appliances are the biggest energy drains?
- Killing 'Vampires': Saving Money and Power by Turning Off Computer Peripherals: investigate how much energy different peripherals attached to your computer (like printer, speakers, and monitors) use.
- Green Your PC: Help Your Computer Save Power: track your computer's overall energy usage and explore the various power saving settings to see what difference each makes. Is putting your system to sleep as good as turning it off? Test different computers in your house to compare the usage by older and newer systems, too!
Bringing Energy Usage Issues Home
Consider these projects as a framework around which you can develop a family science activity. You will need to invest in at least one energy monitoring device, like the Kill A Watt Electricity Usage Monitor. (Investing in more than one would allow you to gather data about appliances and devices in multiple rooms at the same time, but you can track your energy with a single device over time.)
The Kill-A-Watt device helps you see how much power a device plugged into it uses. You plug an appliance into the Kill-A-Watt device, and then plug the device into the wall. With the electricity usage monitor in between your appliance and the power source, you can track how much energy specific appliances use. As shown in the " Killing 'Vampires'" project idea, you can use a multiple-outlet strip to measure the usage of a series of devices.
As you and your family get used to how the Kill-A-Watt device works, and what the numbers look like, you will have a better sense of what you want to test in your own home—and what times of day you want to take readings. (Someone may need to set a middle-of-the-night alarm a few times to get some important data about what always-on systems are doing while you sleep!)
A Whole-family Science Project
Your energy investigation will be specific to your family, your home, and your lifestyle. But here are some general tips for getting started:
- Get the last few energy bills out and show the kids how much power was used—and how much it cost.
- Take a field trip to the basement, garage, or exterior house location to show them the electricity meter and explain how the power company collects the data.
- Talk about vampire power consumption. This kind of continual power drain is also called phantom power or leaking electricity. What does it mean?
- Make a list together, as a family, of all the devices that are plugged in around the house. How many plugged-in things are there?
- Identify which devices are rarely, if ever, turned "off" (e.g., coffee makers with a heating device or clock, cable box, router system, etc.). Are there any devices plugged in that really don't need to be (e.g., a radio that is never used, a freezer in the basement that no longer works, etc.)?
- Work together to make predictions about which devices use the most energy.
- Set up a plan for what devices to measure. Let one of the kids be the record keeper for the project, or have each kid keep the data in a notebook so that everyone can "do the math" and see the data throughout the project.
- After making a list of which appliances and devices to test, first monitor usage of each appliance or device without making any changes. (Be sure and note your start and end usage on your household meter.)
- Be sure and run tests for active use as well as for phantom or vampire use on devices you think may be powering on, actively processing or making connections to a network, or otherwise staying "alert" even when not being immediately used.
- Run tests to see what difference there is between putting a computer to "sleep" and fully shutting it down. One may seem more convenient, but how do they compare in terms of energy usage?
- After gathering power consumption data about the various devices in the house, identify ones that could or should be completely turned off more routinely.
- Come up with a "green" plan for your house and family. Implement the changes you've identified. (Be sure to note the starting number on your household electric meter.)
- After a set amount of time, compare your results pre- and post-change. Did your changes make a difference in overall household usage? If you time your investigation to monitor usage for one month without changes and then one month after changes, you may be able to compare the bill, too!
Are there changes your family can make, long-term, that will make a big difference in the power you use? We would love to hear about your family's "green" investigation. If you wish to share how it went and what you discovered, email us at firstname.lastname@example.org.
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