The last several weeks I've written about a number of common myths of green building. (Last's week's myth: solar panels are the best way to green a home
.) Here's another: that the energy-conservation features and products we install are enough to ensure that our houses will be top energy performers.
The starting point in greening a home should always be the sorts of features I cover weekly in this blog
: high levels of insulation, good air sealing and weatherization, efficient heating and cooling equipment, energy-efficient appliances and lighting, and renewable energy systems. But these systems aren't enough to ensure that our energy bills will be low. How we operate our houses also has a huge impact.
To use an extreme example, even a superinsulated house with R-50 walls and triple-glazed windows will use a huge amount of energy if we leave the windows open all winter. Most of us would never do that--but we do leave the lights on and run water unnecessarily all the time. Below are a few strategies to help us save energy through thoughtful operation of our houses:
1. Turn off the lights.
Lighting spaces that aren't occupied wastes energy, pure and simple. No matter how efficient the electric lighting technology, turning those lights off saves more energy. Turn off the lights when you leave a room; if you can't remember to do that -- or if others in your family can't -- install occupancy sensors that turn off lights automatically after a room has been unoccupied for a certain length of time. (I like manual-on, auto-off occupancy sensors, so the lights don't turn on when your cat walks into a room.) For outdoor lighting, if we can't remember to turn lights on and off manually, motion sensors can be used to turn on lights only when needed, and photosensors will turn them off during the day.
2. Use task lighting.
Often, we don't need to light up a whole room. By turning on lights only where you need them -- a practice known as "task lighting" -- we can save lots of energy.
3. Take shorter showers.
Heating water is one of the two or three largest energy uses in most homes -- and as we improve the energy performance of our building envelopes (insulation levels, air tightness, windows, etc.), water heating becomes proportionally more important. Showers are typically the largest use of hot water in homes, and we can save a lot by not only installing low-flow showerheads (less than 2.0 gallons per minute) but also by taking shorter showers. A shower control that lets you turn the flow down while shampooing or lathering is another great way to save.
4. Don't leave the faucet running.
In the bathroom, avoid the temptation to leave the tap on while brushing your teeth or shaving. In the kitchen, don't pre-rinse dishes before putting them in the dishwasher, or if you must pre-rinse, turn on the water for just a few seconds to do so -- and use cold water.
5. Fill up the dishwasher.
Most dishwashers use almost as much water with a half load as a full load, so you can save a lot of water and energy by waiting to run the dishwasher until it's full. Maybe you'll have to buy a few more dishes, but you'll save money in the long run if this permits you to run the dishwasher only every second or third day.
6. Wash full loads of laundry.
The same argument for running full loads in the dishwasher applies as well to clothes washers. Wait until you can run a full load.
7. Hang clothes outdoors.
In good weather, you'll save a lot of energy by hanging clothes outdoors. This will also save wear-and-tear on your clothes. (If you need evidence for this, think about where that lint you empty from the dryer trap is coming from!)
8. During the summer, operate your house to reduce air conditioning use.
With hot days and cool nights (except when it's very humid), it makes sense to close up the house during the day and open it up at night. During the day close windows and also lower blinds if you aren't home (to block solar heat gain). Then at night open the house up to bring in cooler night air. In some places or during some times of year, this can totally obviate the need for air conditioning.
* * *
Achieving energy savings in homes is really a two-part strategy. First, we need the energy-saving technologies and systems in place. But often just as important is how we operate our houses for optimal energy performance. It isn't rocket science, but it does take some common sense. Fancy technology isn't the answer for everything.
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