Ways to be Fuel Smart: Hot Water for Less

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Hot running water is one of the great inventions of modern civilization. Two hundred years ago only a minority of families in North America had indoor running water. One hundred years ago a minority had indoor hot running water. Today, nearly every home has both hot and cold running water at the turn of the tap.

Now water is becoming more scarce and expensive, and heating it up costs more and more. Fortunately, there are many easy ways to conserve water.

Hot water is important in three areas of the home: the kitchen, bathroom, and laundry. These areas combine to make the water heater one of the major energy consumers in the home, whether it is fueled by oil, gas, or electricity. You may be considering a switch to solar or other alternative-energy sources; section 6 will give you some ideas on how doing that can fulfill your hot water needs.

Let’s say, though, that you’re like most people: Hot water is available at a twist of the wrist from at least three faucets, serves one or more major appliances, and is heated by your heating system or a separate hot water heater. You may already know you have a hot water problem. You’re aware of it every time you pay the bills.

By the standards of former times, most of us live like kings. More and more, though, hot water at your fingertips demands a higher price. This section is intended to help you scale down the use and cost of hot water. The suggestions given here can significantly change the way you use hot water at your house, but without uncomfortable sacrifice and with substantial savings as a result. Let’s get at it!


Experts disagree on how hot the water should be in the house hold supply. Some say if you have an automatic dishwasher your water heater should be set at 150°F. Perhaps, if you need something approaching sterilization. Otherwise, even with a dishwasher, 140°F should be plenty hot enough. You can test the temperature with a candy thermometer.

If, however, your hot water heater is set high enough to accommodate the dishwasher, you will waste energy through excessive heat loss. When choosing a dishwasher, look for one with a booster heater. A booster heater raises the temperature of water entering the dishwasher to 140°F; this allows you to set your main hot water heater to a lower setting of 120°F.

Is that temperature important? You bet. Water heating is the second greatest consumer of energy in the home, amounting to as much as 20 percent of the total domestic energy bill. Water heated to more than 120°F will need to be cooled again for almost all purposes, which is wasteful. Turn down the heater thermostat. Each 10-degree reduction in your hot water temperature cuts your water heater’s energy use 3 to 5 percent.

Whether you have a dishwasher or do the dishes in the sink, an inexpensive low-flow faucet aerator with a shut-off saves water and energy. You can flip your water on and off without needing to adjust the temperature.

A good supply of certain items will also save fuel. You may not need two dozen pickle forks, but it’s a rare household that has too many spoons, coffee mugs, glasses, or bowls. If you constantly run short on these items, buy an additional supply — and you’ll run the hot water for dishwashing less often.

What is true for spoons and mugs is also true for saucepans and frying pans. Have some extras of these items, and you’ll run the hot water for cleaning a single item much less often.

With a dishwasher, waiting until you have a full load every time is an important money saver. Letting the dishes, pots, and pans pile up in the dishwasher is much more economical than washing them a few at a time.

The most expensive way to rinse the dishes before putting them in the dishwasher is under a running hot-water faucet. Next most expensive is in a sinkfull of hot water. Best is in a sinkful of unheated tap water.

If plates are crusted with egg, or a pan has beans burned on the bottom, let the items soak for a few hours in unheated tap water. Nine times out of ten that will do the trick at much less expense than a hot-water soak, or a scrubbing under running water.

When shopping for a dishwasher, look for a model that has the Energy Star label. It will have a switch to cut off the automatic water heater; this can reduce energy consumption by up to 20 percent.

You already have a dishwasher with that feature? Well, when you can, watch the cycle dial. When it gets to the last air-dry segment, just turn it to stop and open the door. In the winter a little extra heat and humidity will be added to the room by this process, and those dishes will dry by themselves quite quickly.

Utensils that are used regularly for non-staining jobs like heating water for tea don’t need to be washed. They can be turned over in a sink rack and left to dry for the next use. Similarly, knives used for clean chores like cutting a grapefruit don’t need the whole hot-water cleaning treatment. A quick splash under the cold water faucet and a wipe with a towel will do it. In fact, if you have good knives with riveted wood en handles, that cleaning method is much better for the knife than a hot-water soaking.

The Bathroom

The invention of single-action mixer faucets was a convenience breakthrough but also a serious economy hazard. With that single-spout faucet you get just the water temperature you want and let it run and run. Terrible. It would be better if you still had two separate faucets as older sinks did. Then you’d need to stopper the sink arid mix the right temperature in the bowl. You’d save money. With four people in the house, each one using the bathroom sink, say, five times a day, just filling the sink instead of letting the water run might save as much as 40 gallons a day in hot water. That’s enough for two full loads through the washing machine, or three quick showers.

That quick shower takes about half as much water as a tub bath. Try to think of soaking in the tub as an occasional luxury, and the quick shower as a frequent necessity. A low-flow showerhead can reduce hot water use by as much as 50 per cent. Most people won’t feel a bit of difference or will prefer it to the old showerhead.

When you take a tub bath, don’t immediately drain the water when you’re through. Let the heat from the water radiate into the room until the water is cool. You might even stop per the tub when you take a shower, and let that hot water radiate its heat before it goes down the drain.

Be sure you turn off the faucet all the way when you’re finished using the sink or tub. One drop per second from a hot- water faucet is 200 gallons a month, or 2,400 gallons a year.

Cold Water for Laundry?

Consider using a cold-water detergent. Only clothes that are very greasy need water as warm as 80°F to get clean. Your washing machine probably has settings for cold, warm, and hot water. Use the cold for ordinary washing, the warm for very dirty clothes, the hot not at all. By using cold water washing techniques you could save $10 to $15 a month in hot water costs. With today’s detergents, cold-water rinsing is fully effective, and the rinse cycles use probably half of the water you use in washing.

Running your washing machine for just a few items? Try to avoid this. Perhaps some necessary items are in short supply. Stock at least a week’s supply of the commonplace, most-used items like socks and underwear. It’s cheaper to have enough for each person and use the washing machine less frequently.

A larger supply of frequently washed clothes will allow better use of the different washing cycles. Lightweight items such as underclothes, handkerchiefs, blouses, and pillowcases can take a shorter cycle than heavy weights like blankets, jackets, and towels. Make up full, separate loads of the different kinds of washes you do.

You will need hotter temperatures for some things like baby clothes. Have enough of these, too, so you can make up full loads and make the most of the hot water you use.

When shopping for a new washing machine, look for the versatility of partial-load washing and for the ability to wash at different temperatures. Look for the Energy Star label. Washing machines with this label can use up to 60 percent less energy and 35 percent less water. Be skeptical of overly fussy controls and multiple cycles. All that electronic gadgetry runs with electric current and spins the meter. Once you have figured out which features you need, select the model that uses the least energy.

What About Your Clothes Dryer? You’ve heard the lecture. Do complete loads. Use the most appropriate temperature setting. Keep the lint filter clean. Above all, when buying the new dryer, use the one that uses the least energy.

Six Easy Ways to Cut Hot Water Costs

1. Locate the water heater as near as possible to the places where hot water is used. Water cools as it travels through pipes.

2. Insulate your hot water pipes along the first 6 to 12 feet from the water heater for the greatest savings.

3. Insulate hot-water pipes that travel through unheated areas. Both pipe insulation and wraparound insulation can be bought at most hardware stores and are simple to install.

4. Many new hot water heaters come with adequate insulation. If you have an older model, a hot-water wrap can pro vide significant savings. Contact your utility company or manufacturer for advice and safety information.

5. The water heater has a drain valve at the bottom. Use it about twice a year, or more often if there is considerable sediment in your water supply. Draining the heater will allow the heating elements to operate more efficiently.

6. Need a new hot water tank or a new heating system? Consider purchasing an indirect water heater. A well-insulated hot water tank connects to the boiler. With its own aquastat to regulate temperature the boiler will come on much less frequently, which saves energy, especially in the summer.

Next: Here Comes the Sun

Prev: Your Energy-Efficient Kitchen

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