Choosing Energy Efficient Appliances

Selection of appliances for a solar electric home is perhaps the most important aspect of the design. It is a little different from utility connected homes, and the difference is essential. Be sure you understand this page before shopping for appliances. Your electrician also should understand this appliance page and the Home Wiring page when planning the wiring. Call Backwoods Solar if you have questions.
LIGHTING is more effective, using less power, if you have lots of local area "task" lights rather than a big central light. Use 15 - 20 watt fluorescent lights under cabinets close to the kitchen counter. Use a separate wall switch for each wall/ceiling light so you can turn on lighting precisely where needed. Several small lights save energy by giving more flexibility than one large central light. Compact Flourescent Lighting
Screw in light bulbs should be mostly compact fluorescent lights using about one quarter the power of regular bulbs while giving the same brightness and color. Get only electronic ballast models; they do NOT flicker. Light dimmers should not be used unless you have a sine wave inverter and the bulb specifically states dimming is OK.
Timer light switches are great for lights turned on and often forgotten, as in children’s rooms, closets, stairwells, and particularly basement and outdoor lights. Timers keep the peace when lights are frequently forgotten. The tap of a electronic timer button or a wind up light switch timer starts the light and sets the run time you choose from a few seconds to an hour, after which the light goes out. Windup light switch timers are in the lighting section of the catalog.
 Motion sensing lights outdoors are great for arrival and departure. An AC motion detector will not turn lights on when needed unless you force your inverter to run full time. If the inverter is at idle (search) mode, the sensor will not work. A 12 volt DC powered motion sensor is the answer. It's on duty all night with almost no power use.
WALL CLOCKS AND TIMERS Clocks should be quartz type and battery powered; not plug-in AC powered. Timers for automation or wake-up radio should be DC powered, not AC. Several timers are available.
REFRIGERATOR / FREEZER Older ,Standard, non-Energy Star refrigerators and freezers use so much power battery charge is depleted very quickly. With solar electric powered homes, it is not practical to use these older, standard electric refrigerator or freezer. Super efficient refrigerators designed and tested for solar power, listed in Backwoods catalog, operate on less than half the usual power.
Ordinary AC refrigerators and freezers run on over 200 watts AC, and run many hours a day. Most have less than 2 inch insulation. Fortunately, special refrigerators and freezers are available which use less than 30% as much energy. Efficient Refrigerators
SUNFROST products have 4- to 6-inch insulation, and a quality compressor on top where it can’t put heat back into the box. The RF-12 model runs 50 watts for 12 hours a day, totaling 600 watt hours a day. This needs only 3 to 6 solar modules, depending on the climate. The price is higher than an average refrigerator, but considering the whole solar power system, the total cost is lower than using a $300 refrigerator plus equipping the home with the extra solar modules it would require.
NovaKool is a small DC refrigerator made for RV/marine markets. With the same Danfoss compressor as the Sunfrost, these little refrigerators are 1/3 the size but are not as well insulated so use the same amount of power as the larger Sunfrost. However, if you glue 2 extra inches of foam insulation to all surfaces except the door you can cut run time in half, and reduce consumption to about 300 watt hrs/day.
The  CROSLEY 12.2 cubic foot chest freezers are a regularly available freezer from Canada which is as well insulated and energy efficient as any we sell, and at about 1/3 the cost of special solar designed brands.
GAS : A refrigerator’s need for power matches solar electric's increased production in summer and less in winter. But a gas refrigerator can relieve a large electrical load from a power system, and cut the initial cost of a power system. Added solar modules for electric refrigeration raise the up-front cost, whereas propane gas is paid over 15 + years. Cost comparison is close either way (if gas prices don't rise).
CAUTION: COMBINATION GAS-ELECTRIC refrigerators are usable only as GAS POWERED, not as electric. They use an electric heater, running nearly full time, to replace the gas flame. They use much more power than an electric compressor type, so they work well only as GAS. Backwoods Catalog lists several gas (propane) refrigerators which use less than 1/4 gallon of propane in 24 hours.
Appliance efficiency listings: good information is now available at:
 http://www.appliances.energy.ca.gov/
and also at http://www.energystar.gov/products.

WATER PUMP DC pumps use very little power. 12 or 24 volt models can pump from well depths as deep as 750 feet. 120 volt AC pumps, 1/3 or 1/2 horsepower can operate from inverter power, lifting water from 300 feet down. Many more details are on our pumps page in the catalog section of this website.
COMPUTERS
Windows type computers run on any inverter. A few Apple / McIntosh computers may require a "true sine wave" inverter, but most do not. Laptop / notebook computers use internal batteries, and recharge from any small inverter using just 20 to 50 watts AC power. Most manufacturers offer an optional car-cord to operate directly from a 12 volt battery at very low power.
Laser printers (and most photocopy machines) can be damaged by modified-sine wave inverters. Inkjet and dot matrix printers are no problem, and use very little power. At Backwoods Solar, four computers with printers run 8 to 12 hours a day. HP laserjet printers automatically idle to just 7 watts between printing, or a switch can be used to shut your printer off. An outlet strip with switches off all computer equipment after shut-down to prevent phantom load leakage. 
For true sine-wave operation the whole home/office may be powered by a large sine-wave inverter. Alternatively, one of the smaller true sine-wave inverters may be added for just the computer, and a separate circuit run from it in the battery room to an outlet by the computer.
HEATER / FURNACE / HOT WATER FLOOR HEAT  Propane Heaters
Use propane, natural gas, oil, or wood heaters and furnaces, never electric heat. Electric heat pumps also use substantial amounts of energy, less than resistance heat, but way too much for independent power. They are reversible air conditioners. Also beware of ducted forced air and blowers. Common in manufactured homes, the blower takes much more power than can be justified.
Propane direct-vent (through the wall) heaters in the non-electric appliance section of this catalog save fuel because each room can have its own heater and wall thermostat. No circulation blowers are needed so they work with no electric power. This is the easiest and lowest cost installation and is effective.
Wood or gas furnaces located on bottom floor or basement in a multistory home allow heated air to rise by convection from lower to higher floors without high powered fans or ducted blowers. Larger ducts for natural convection circulation can work with no power blower needed, or a very low power quiet DC fan from our DC appliance section to boost output. These low power fans can also increase efficiency of gas heaters or wood stoves by moving air over the surface. Some home designs add a space along side a masonry chimney as a hot air duct to the upper floors, and perhaps also run water pipes through it. Each stairway should have a door to control rise of heated air.
Floor heating by hot water circulation requires power to circulate water. Use of 1/2 inch or 3/4 inch floor pipes allows a lower power pump. Use a separate DC circulating pump controlled by a thermostat for each zone, rather than one big pump with zone valves. We have seen serious power problems using special boiler systems & zone valves. We have seen success using tank type fast recovery propane gas hot water heaters or large wood fired boilers that heat water directly in the storage tank. Remember floor circulation heating brings added demand for power at the season when you have the least power. See Home Power Magazine issue 79 page 36 for more. You can also warm water beds and compost toilets by circulating hot water from the tank through coiled pipes under them and back again, with a DC cycling timer to control the pump.
CLOTHES WASHER Energy Conserving AC Appliances
Most top-loading, agitator type clothes washers work fine with a minimum 1500 watt inverter. They consume 800 watts while running. A starting surge of about 3000 watts is required. A motor start capacitor can be added to any washer that has a start winding wire on the motor (not Kenmore or new electronic units) to lower the starting surge. Order item A-CAPACITOR: $20
Electronic washers by Staber, Whirlpool, Frigidaire (model GLTF1670) and Maytag Neptune use much less power, less water, less soap. Some of them require a sine wave inverter, will not run on a generator, and void their warranty when used with generator or inverter power. Staber, listed in our catalog section, uses only 160 watts-hours per load, does not need sine wave power, and the factory is happy to sell to renewable energy users. Staber can really save energy if you do a lot of laundry.
120v AC gas heated clothes driers can be used, not electric heat. New condensing type driers use a great deal of electrical energy.
KITCHEN STOVE   Electric stoves are out. Propane or natural gas stoves with gas pilot light need no power connection at all. Spark ignition burners use very little power and work fine with inverters. Do not buy a gas range with electric glow bar as oven pilot light. This is an electric red-hot glow-bar pilot in the oven that consumes 400 watts all the time the oven is used! Instead, look for one of two types of pilot light oven. An oven with regular gas flame pilot light is the simplest. Better is an oven pilot that lights by electric spark when oven is started and goes off when oven is finished. Both types are available on the Peerless Premier propane range from our catalog.  Also the AC clock in some ranges may act as a phantom load, keeping the inverter running full time. If so, disconnect wires to the clock so you can plug in the stove to use the oven light and spark igniters. Range hoods with light and vent fan work fine with inverters. Be sure to put a compact fluorescent bulb in it.
Non Electric AppliancesWATER HEATER Electric water heaters are out. Use a natural gas or propane tank heater from plumbing and hardware stores. Get one with a pilot light, not glow-bar ignition. Vent all gas appliances straight out through the roof to avoid power wall vents that seem easy to install but use substantial power ever after. Perhaps try an instant tankless water heater shown in the non-electric appliance section of this catalog. A video showing how to install and use the Paloma tankless water heater is listed at the book and video section of this catalog. Wood fired cabin size water heaters are also in the non-electric appliance section.
SHOP & POWER TOOLS Most hand-held power tools operate from 800 or 1500 watt inverters. Larger power equipment like table and radial saws usually work with 2500 watt inverters, though sometimes the motor belt needs to be manually slipped for easier starting. Sinewave inverters rated 4000 watts work best for large equipment like table saws and smaller air compressors, which have very large starting surges. Select small wattage 120 volt models or use a generator or 4000 watt inverter to power these tools. Many cordless tool rechargers, the ones without a wall cube transformer plug, must have only true sine wave inverter power, and can be ruined on modified waveform inverters, but you can often obtain a 12 volt charging stand from these tool companies.
STEREO, TV, VCR, SATELLITE TV TV up to 19 or 20 inch uses about 85 watts and works with any inverter. Some larger screens use more power, but work fine if you allow for the extra power. VCR and some satellite units use only 20 watts. SATELLITE TV works great on inverter power. RCA/Sony Direct Satellite System (DSS) is used at Backwoods Solar, only about 15 watts. STEREO of good quality usually works with any inverter. We recommend JVC or Kenwood, from www.crutchfield.com., as these typically have no problem keeping settings or memory while disconnected from power. Inverters rated above 300 watts will run all of these items. A few large screen TVs require a true sine wave inverter. 
Almost all TVs, VCRs, satellite, and stereos consume power even when switched off. It is important to use a wall switch, or a switched outlet strip to cut all power off from this equipment when not actually in use. 
PHONE MESSAGE MACHINE and FAX Phone message machines and fax machines, if left on, use small amounts of power 24 hours a day which adds up to a large load. 
DC TO POWER MOST PHONE MESSAGE MACHINES Any answering machine can be run on AC power from your inverter, but since they are usually powered 24 hours a day, this uses more power than we would like to spend. Many phone answer machines can operate direct from 12 volts at very little power consumption. These cannot be directly connected to a grounded battery system, or they put a ground hum on the phone line and disable it. Also available are voltage converters for 24 or 48 volt batteries to 12 volts. 
FAX AND MESSAGE MACHINE AUTOMATIC AC POWER SWITCHER:  Backwoods Solar sells a custom switcher that powers up AC inverter power to the fax and/or answer machine when the phone rings, and turns it off some minutes later after the call is received. Simple FAX with thermal paper rolls work well with this because they warm up instantly to answer the phone as soon as power is connected, and use very little power. Plain paper fax of inkjet design will warm up to answer within 5 rings. Many laser fax machines can not warm up fast enough to use this method. See further information in the FAX TIMER listing. 
Recently most phone companies offer a voice-mail message service just like an answer machine, but works through your telephone, for a monthly fee. Advantages are that no power is required, you don't need to maintain a machine, and it even takes messages for you if your line is busy.
CORDLESS PHONES  work on direct 12 volt DC, very low power, to avoid keeping the inverter on 24 hours for so small a load. We now carry a DC Isolator that will allow your choice of 12v DC phone run on a 12 volt battery system without conflicting ground issues. They work anywhere around the house, eliminating the need for extra phone wires and jacks.
TELEPHONE BEYOND THE LINES  If phone lines cannot reach your site, and you don't want to pay time usage on cellular, a radio relay phone link up to 15 miles line-of-sight can connect you to the nearest phone line. The radio link brings in phone, modem, answer machine or fax. Ask us for sources. Microsoft's fast two way satellite direct internet service with NO phone line required is now available through Radio Shack stores.
AIR CONDITIONING: So much power is consumed with such long running hours that air conditioning is usually considered impractical on solar power. The smallest 600 watt window unit is actually possible to run during sunshine hours given a large solar power system, but can add $4000 to power system cost. EVAPORATIVE COOLERS work very well, (except where very humid). Low energy 12 and 24 volt DC coolers of larger size than in the past are now available in our DC appliance catalog page.
DISH WASHERS Dishwashers work fine, with one caution. There might be two high power heaters, one to dry the dishes and sometimes one to superheat incoming water. You should be able to disconnect or switch off these heaters to save a lot of power.
FOR OTHER ITEMS NOT LISTED
CALL FOR ADVICE (208)263-4290 or Email info@backwoodssolar.com

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Email: info@backwoodssolar.com		 Backwoods Solar Electric Systems
1589 Rapid Lightning Creek Rd
Sandpoint, Idaho 83864 USA