One of the biggest problems for those of us who understand the need to pursue sustainability is to know what to do. There is far too little information available about how to conserve energy, minimize one’s carbon footprint, and make a positive move towards living sustainably. Just when you think using paper bags is more ecologically responsible than plastic bags, someone figures out that the energy required to make the paper created more pollution than the processes that produced the plastic bag. Then, some time later, someone else tells you that the paper comes from renewable trees while the plastic is made from non-renewable oil, and paper is therefore more responsible. There are so many pieces of conflicting information flying around in the media that it is daunting, and a lot of people give up trying. Perhaps I can throw a very tiny bit of light on this topic with a simple idea, the common electrical outlet strip, backed by some simple calculations.
When population is great, small, widely-observed practices can make a big difference. The media has long told us that wall chargers use power whenever plugged in, and not just when the device they power is turned on or charging. Such devices have even been nicknamed “vampires” because they “suck” small amounts of power when not in use, taking a “bite” out of your electrical budget and necessitating more highly-polluting power plants. If you touch a wall charger or power supply when it is not powering anything it will feel warm; a sure sign of wasted energy. While it may only take a few watts to warm the case, consider how many of chargers are drawing power in your house. Then consider the energy required to power the devices of more than 300 million Americans, and you start to get a sense of the scale of this problem. At a conservative 2 watts each, the wall chargers of Americans use the energy output of a medium-sized coal-fired power plant, more than 250 megawatts.
Electricity “vampires” are everywhere. Devices such as TVs and stereos, and most devices that have remotes or any features called “instant on”, also draw power continuously and have a power switch that is really a standby switch. Some may have a main power switch hidden somewhere, but what looks like a power switch is quite often only a standby switch. While today many wall and table clocks are battery powered, any appliance with a clock has to power the clock circuitry or mechanism and probably draws electrical power to do so. Anything with a remote has to keep a receiver powered on in order for the remote to work. Some devices require large power supplies that draw proportionally more power than a cell phone charger. Basically, anything that feels warm when it is turned off is probably drawing power continuously.
Some devices have to be vampires. Before you start unplugging everything, think on this: a great many electrical devices we use today (2010) were designed to stay partially on (on standby) all the time, and turning them off may impair their effectiveness or create inconvenience for you. Hopefully that will change as the need to save power becomes more prominent, but for now it may be necessary to let some vampires suck power. Is a furnace or refrigerator a vampire since its controls require continuous power?
A curious case in which data bandwidth is a factor. My cable TV tuner is always hot to the touch and has a lot of vents in the top – sure signs of a “power hog”. If I unplug the tuner when I’m not watching TV, when I turn it on again it won’t be able to display programming information until it reloads that data from the cable TV network, and the listings gradually appear over a period of 45 minutes or so. Apparently the data bandwidth in the cable TV network is too small to load the programming information very quickly. Perhaps someday that will be improved, but for now it discourages me from disconnecting the power to the cable box, even though it wastes a lot of energy.
The simple solution: a switchable outlet strip. Devices that don’t need to be on all the time can be plugged into a control of some sort, the cheapest of which is probably a multiple-outlet power strip with a switch. If you plug your cellphone chargers and similar electrical devices into a switchable outlet strip it is easy to control them and be sure when they are on and when they are truly off. While a decent outlet strip can be had for $5 or less, it is possible to spend considerably more. Whether the extra cost is worthwhile is questionable.
The payback period for an outlet strip can be fairly short. I have an outlet strip next to my bedside into which I plug the chargers for two cellphones, my laptop computer, and my CPAP machine (used to treat my sleep apnea). If each of the cellphone chargers draws 2 Watts when not in use and the other two devices draw 4 watts each, all I have to do is turn off the outlet strip when I leave in the morning and turn it on when I come home, and I am saving 12 watts continuously for 12 hours per day. In that fashion I save 12 x 12 or 144 watt hours per day. Since I pay an average of 13.7 cents for each kilowatt hour, I am saving (144/1000)*.137 dollars per day, or $0.005328 per day. Since an inexpensive outlet strip can be found for perhaps $5, if you remember to turn it off most of the time, perhaps 250 days per year, you will save $1.33 per year, and the outlet strip will pay for itself in 3.75 years, which is not bad for a device that can last decades. That payback period will be shorter if rates go higher, too.
There is power in numbers. You also save the power company having to generate 12 watts for most of each day, and if 10 million people do that in the United States, it can save a lot more. Due to inefficiencies in the power grid and the need to handle peak demand, generation capacity must be maintained at a level that is around ten times the actual power demanded. That means that 12 watts of electricity demand must be supplied by a capacity of 120 watts. The same 10 million people, by putting their chargers on an outlet strip and turning it off when not in use, avoid the need for 1,200 megawatts, which is the capacity of a large nuclear power plant or up to five coal or gas-fired power plants. Personally, I have no problem investing $5 to avoid the need for another giant power plant with all it will cost to build and all the pollution it will produce.
Surge protection, an outlet strip extra, is not worth the expense in many cases. One of the most popular extras among outlet strips is surge protection. I have had many outlet strips that advertised “surge protection”, and have even paid extra for strips that had the added capability. I have also installed surge and transient protection in an outlet strip, adding appropriate capacitors and metal oxide varistors (MOVs) inside the outlet strip. More recently, however, I have read how relatively cheap MOV’s can explode or burst into flames when hit by a major power surge, such as when lightning strikes nearby. For this reason I rarely use a surge protection-type outlet strip unless there is no other protection and I am using a power source with a higher than normal risk of surges and spikes, such as that from my portable generator or in an area where power is often interrupted. Since I own my own home, I had an electrician install a proper commercial surge protection unit in the circuit breaker panel (cost is usually under $500 for the surge protector and labor combined). With this protection in place I don’t worry about damage from surges and spikes, nor do I ever need surge protection in my outlet strips.
The path to a sustainable civilization will be built on many small changes such as using outlet strips to conserve electricity. As you can see, if only 10 million individuals in the United States used an outlet strip to stop electricity being wasted by “vampire” devices, it could avoid the need for an entire nuclear power plant costing perhaps a billion dollars. In the future more of our electrical devices will be built to be more efficient, and those that require standby power will make more efficient use of it, but today there are many power-sucking devices in our homes that are just wasting energy. Every bit of energy we can save today moves us closer to sustainability and buys more time to get our population growth and pollution under control, and an outlet strip can be a sound investment in the future with a very reasonable payback period.
As always, I welcome your comments. Thanks for reading this. – Tim
No comments:
Post a Comment