Living on 12 volt solar power for zero EMF
Part 3 – Appliances
This is the third part of the article series about low-voltage solar systems for living without EMF. This article covers the various appliances, such as lights, pumps, refrigeration and heating.
Other articles are available at www.eiwellspring.org/offgrid.html
Table of Contents for Part 3
10.1.1 Outdoor lighting
10.4 Telephone system
10.5 Washing machine
10.7 Air conditioning
10.8 Water heater
10.9 Home electronics
10.10 Phantom loads
11. Heating an off-grid house
Household appliances include lights, refrigerator, washing machine, pumps, electronics and all sorts of electrical gadgets.
A solar house must have a lot fewer gadgets than the typical American home. It is simply not feasible to run it all on solar, and especially not on small 12 volt systems. See part 1 of this article listing items that are not really possible to use in such a house.
Appliances that use motors or electronics may not be compatible with an ultra-low EMF life, and should be used sparingly or away from the sensitive person.
The solar system must be sized to power the use of the chosen appliances.
The voltage produced by a solar system varies and can be anywhere between 11.5 volt and 15.5 volt. The typical daily variation is from 12.5 volt to 14.5 volt. Any appliance connected to the solar system must accept this variation. This author has tested multiple 12 volt devices, such as radios, TV, DVD player and laptops, which all have worked fine, but some models may not like such a variable voltage.
Lights of all kinds (incandescent, halogen, LED) tend to run hotter with a higher voltage than about 13 volt. This may shorten their life span. This is a particular problem for LED lamps.
Many 12 volt appliances come with a cigarette outlet connector. They will not fit into the outlets suggested here. The solution is to either make a conversion cable or replace the cigarette plug with a new plug. Make sure the polarities are correct, as reversing plus and minus can ruin many appliances.
For 12 volt and zero-EMF, there are only three types of lighting available:
The incandescent bulbs are the cheapest, but also the most wasteful of electricity. They are best used only where they are on briefly, such as closets.
Halogen bulbs are about 20% more efficient than incandescent bulbs, but also cost more. The halogen bulbs send out some UV-light, but that is largely blocked by glass. Most models come with a glass enclosure and putting it in a glass fixture should block most UV.
LED lights are costly, but are a must where the lights may be on for many hours. This especially includes where the lights may be accidentally left on, such as porch lights.
Most 12 volt LED lights do not have built-in electronics (unlike 120/240 volt models, which all do). A few 12 volt models do have electronics, which are best avoided in a low-EMF home.
The quality of the light from LEDs takes some time to get used to. Some sensitive people cannot tolerate it, so experiment. Some people do better with LED lamps that are reflected off a wall or ceiling. They are getting better, and this may soon not be an issue.
There are very few 24 volt lights available. Currently, the selection is limited to a few LED lights and some automotive light bulbs. An alternative is to wire two 12 volt lamps in series or build your own.
LED lamps run hot when the voltage is above 13 volt. This shortens their life and may result in dead or flickering LEDs. It is best not to run LED lights during the day, or while charging with a generator, where the voltage will rise above 13 volt.
10.1.1 Outdoor lighting
Visitors to off-grid neighborhoods often notice the lack of “security lights” (and how bright the stars are, due to the lack of light pollution). Brightly illuminating a house is not really realistic with 12 volt solar systems, and it is rarely needed anyway, as they do not deter burglars.
LED lights are a must for outdoor lighting, as they are so efficient. For people who can’t tolerate LED lights, much can be accomplished with driveway reflectors and motion detector activated lamps.
The choice of refrigerator is limited to either 12/24 volt models or a gas fridge. It costs about the same to purchase either type, when including the solar panels needed for the 12/24 volt models. As a propane refrigerator consumes about two gallons (9 liters) of propane a week, the solar powered models are the most economical in sunny climates.
A gas fridge should not be kept inside a house, as it does emit combustion fumes. Some people keep them in a closet on the outside of the house, on a porch or in a garage. Some people have attached chimneys to them, though some fumes may still get into the room. RVs have direct venting of gas refrigerators, which seems to work well.
However, a gas fridge is totally noiseless and can be totally free of EMF emissions. This may be the decisive factor for a low-EMF house.
Beware that some gas fridges have built-in electronic controls, which may be a problem. These controls cannot be turned off. Check before buying.
The 12 and 24 volt refrigerators use DC motors. A DC motor puts out a lot more EMF than an AC motor, and it backfeeds strong dirty power onto the house’s electrical wires. In a low-EMF house, these types would need to be in an outbuilding and preferably fed by a separate solar system to prevent backfeeding.
A third option may seem to be some RV fridges, which use either 12 volt or propane. However, these have an electric heating element which consumes 200–300 watts, which is way too much electricity to be viable for a solar system.
The small 12 volt thermoelectric coolers are not very effective. They also use too much electricity and the DC fan motor is problematic.
Some people have gotten along for years using ice chests. A well-insulated large cooler would need a bag of ice about three times a week. It cannot keep things frozen, but it works well for refrigerated foods.
A rural home often has its own well, which means there are one or two pumps. There may also be a circulation pump for a hydronic heating system.
There are several 12 and 24 volt pumps available for various uses. A pump must be selected for each specific situation.
For a shallow well, one pump may be sufficient. For a deeper well, there may be one pump that pumps to a holding tank and another that takes water from the tank and fills a small pressure tank.
The well may be serviced by a special pump that runs off separate higher voltage solar panels or a small wind generator. This tends to be rather expensive.
A cheaper solution is to have a conventional 240 volt pump in the well, which is now and then powered by a generator, while filling the water tank. The generator could then also power a washing machine at the same time.
The noise level, amount of dirty electricity and EMF emissions can vary greatly among pumps of the same type. This author tested two circulation pumps and found the LAING D5 model superior to the EL-SID.
The water pressure in an off-grid system is typically lower than a city or an on-grid system, to save resources. The booster pump typically comes on when the pressure drops to 20 psi (1.4 bar/140 kps) and stops when it reaches 40 psi (2.8 bar/280 kps). A pressure tank of nominally 20 gallons (76 liters) strikes a good balance between the pump coming on too frequently, versus running for a long time, which can be hard on the battery.
Pressure pumps are noisy and best located in an outbuilding. If placed in the house, it could wake people up at night. A remedy could be to use a large pressure tank and then ensure that it is filled at times when the noise is acceptable. If using a large tank, the pump would run for longer times when it does run. Make sure the battery is up for it.
Some people put their pumps on a separate solar system. This prevents dirty electricity from travelling on the household wiring. A separate system could also be used for well pumps that requires a higher voltage, such as 48 volts.
The lower water pressure in off-grid houses is rarely a problem, though a reverse osmosis (RO) water filter would probably need a non-electric pressure booster.
The pumps used can usually produce about 3 gallons per minute (34 l/min). This works for a household with one or two people, who can simultaneously run two faucets (low-flow slower and toilet or sink).
10.4 Telephone system
A simple telephone is powered by the telephone landline and does not need electricity from the solar system. This is often the best solution.
Fancier phones and caller-ID displays that are not battery powered are on 24 hours a day, so even though they may not consume much wattage, it may add up over time. Such phones can also backfeed dirty power onto the house wiring and may not be a good idea for very sensitive people.
Cordless phones always consume extra power and also radiate 24 hours a day. They simply do not belong in a low-EMF home at all.
Answering machines should be avoided. If voice mail is available, that is a much better solution. If an answering machine must be used, there are devices available that first turn it on when the phone rings, and to possibly power it directly on DC. See the catalog from Backwoods Solar for details (see resources).
10.5 Washing machine
A washing machine is essential for sensitive people, as using a laundromat is likely to contaminate the clothes with fabric softener, fragrances and other chemical products used by other people.
There are no low voltage DC washing machines available and the little hand-cranked camping models are not practical for daily use.
Two options available are to power a 120 volt model with:
• a generator
• an inverter from the solar system
The generator option is usually the simplest, cheapest and safest for a sensitive person.
Using an inverter would require a larger solar system and the inverter may be intolerable. The Staber brand washer is specifically designed for use with an inverter, and it consumes much less electricity than regular models.
A third option is to have a dedicated washer located at someone else’s house.
In some climates, it is feasible to hand wash and line-dry clothes year round. Lehman’s sells a plunger-like washing device, and a washer with a paddle-mechanism, which both work well (see resources).
Cooking using solar power is not realistic, especially not with a 12 volt system. A solar cooker can be a great help in a sunny climate, but it cannot do it all, even in the hot desert.
Some sort of gas-fired stove will be needed. It will need to be outside, or in a separate extremely well ventilated room or enclosure. Totally outside is best, for instance on a porch, sheltered from the wind.
A simple camping stove can work very well. A gas-powered bar-be-cue grill is a great complement, both for grilling food and also for baking foods (cover the grill with two cookie sheets).
Full size gas stoves are available, though most actually do require 120 volt AC to function. Only two companies in the U.S. manufacture non-electric gas stoves: Peerless-Premier and Brown Stove Works. Verify that the selected model does not require any power.
10.7 Air conditioning
Air conditioners can simply not be run from a 12 volt solar system. They consume too much electricity.
Swamp coolers can be used in dry climates. There are 12 and 24 volt swamp coolers available (see resource section). These do use DC motors which can be very bothersome to sensitive people and may need to be run from a separate solar system. A swamp cooler also makes a house humid, which can promote mold growth. The pads may contain biocides as well. Swamp coolers work only in dry climates.
Some people design their house for passive cooling, using large roof overhangs to shade the house, smaller windows, low-E glass, thermal mass and other methods. This may not be enough in a hot climate.
10.8 Water heater
For heating water for bathing and chores, there are four options:
• propane/natural gas
Some woodstoves can also heat water. Some models can be used outside, perhaps only fired up once a day for hot water.
Solar water heaters may provide hot water for some or all of the year, depending on the climate. Some people bathe in the afternoon on winter days, when hot water is available, and not at all on dark days.
A gas-fired water heater is probably the best option for most people. It works very well if kept in a separate ventilated space that is sealed off from the rest of the house. Most gas water heaters do not require any electricity, but some fancy models do. Make sure the gas line does not at all come in through the house, as they tend to leak with age.
A generator can be used to power an electric water heater, but that is a very expensive way to heat water, besides the other drawbacks such as noise, EMF, inconvenience, etc.
10.9 Home electronics
Home electronics such as computers, TVs, radios etc. are usually problematic for very sensitive people. But many of us do use them to a limited extent.
A battery powered radio is a common example. Some larger radios and boom boxes can be run directly from a 12 volt system. A regular car stereo can also be used on 12 volt.
There are 12 volt televisions and DVD players available from some large truck stops, RV stores and places selling car electronics. Brands include NAXA and Skyworth.
A more elaborate setup is to have a satellite TV receiver located on an outbuilding, which houses a DVD recorder. The recorded DVDs are then played on a DVD player inside the house. The outbuilding should have its own totally separate solar system and a small sinewave inverter (250 watts or so) to run the electronics. Such an outbuilding should be located about a hundred yards (100m) from the house.
Most laptop computers can be run on 12 volt. A special cigarette-outlet cable may need to be purchased. They are usually more tolerable when run from the internal battery, so some people only use it that way and charge it up again while they are not home.
Fast internet service, such as DSL/ADSL, coax and fiber-optic may be more difficult. They all require a sophisticated modem that is powered by 120 volt AC. The modem can be turned off when not needed, but powering the modem from a 12 volt system without an inverter may not be possible. Some models may use an external power supply. In that case, it may be possible to replace the power supply with the household 12 volt.
Electronics which need a lower voltage (such as 6 or 9 volt) could be served by throw-away or rechargeable batteries. It may also be possible to run them from the 12 volt system using a linear power supply (not a voltage converter). A linear power supply can be made by someone handy with simple electronics, the component needed is called LM317.
Very few pieces of electronics require more than 12 volt. This author has only seen a water softener and a few printers and fax machines.
If a necessary item needs more than 12 volts, it may be necessary to build a small separate 24 volt solar system to power it, or use disposable/rechargeable D-cell batteries.
Fax machines, inkjet printers, etc. may also be powered by 12 volts for certain models that have an external power supply that generates 12 volts or less (check the label). It is not realistic to power laser printers and large photocopiers using 12 volts, as they use too much electricity.
10.10 Phantom loads
The phantom loads are things that consume electricity round the clock, even though they are turned “off” and are not really doing anything that matters.
Examples of phantom loads are clocks, some TVs and radios, cordless phones, idling computers, battery chargers, etc. In a typical American home, the phantom loads can be quite substantial. In an off-grid ultra-low-EMF house, they should be eliminated.
11. Heating an off-grid house
There are not many realistic options for heating a house safely and with only low-voltage electricity. They are basically:
– propane/natural gas
The sun can provide a lot of heat in sunny climates, but in almost all cases some other heat source is needed as well.
Some people with MCS use wood heat and do well with it, but many cannot tolerate the smoke. It is important to use a high quality wood stove to reduce the smoke around the house. The main exposures to smoke and soot are then when servicing the wood stove.
Pellet stoves require electricity for the feeder mechanism and are probably not practical for 12 volt off-grid homes.
One option is to buy an outdoor wood furnace which heats water that is piped into the house. They are only serviced once or twice a day, but it is still a lot of smoke exposure to maintain it.
Propane or natural gas can work very well if the fumes and any gas leaks are kept strictly outside the living space. This means
• no gas appliances in the house
• no gas pipes in the house
• no forced air heating
In practice, that means the boiler/water heater must be outside the house, in an outbuilding or a closet on the side of the house. The house is heated by hot water piped through the floor (in-floor heating) or radiators. It may be possible to retrofit in-floor heating or radiators in an existing house.
Some manufacturers claim their products have sealed combustion chambers, but experience shows they do not work for people with MCS.
An alternative is direct-vent heaters that are mounted on exterior walls in each room of the house. They take in fresh air and return exhaust directly through the wall. The record for these is spotty, and they cannot presently be recommended.
Any other type of heater, regardless of claims of “catalytic” or “vent not needed” will probably not work for sensitive people.