After I had been well for over eight years, we were faced with the prospect of forced installation of transmitting utility meters or having our power cut off. The former was not an option, since we knew how sick we would all be. So, we began researching how to be independent of the utility, safely.
People, including us, who are contending with illness due to exposure to radiofrequency radiation either from "dirty" power or transmitted radiofrequency radiation (wireless technology) often think that going off-grid with a DC (direct current) electrical system will solve their problems.
Unless the system is carefully researched and engineered, meticulously installed, and then appropriate filtering is installed to eliminate the radiofrequency signals that inevitably result from the operation of most components available today, this will NOT be the case.
Most DC systems are inherently polluted with high frequencies due the equipment that is used within the system. This can be measured with a specially designed Graham/Stetzer Microsurge Meter. The Graham/Stetzer Microsurge Meter gives a good indication of whether the electrical pollution present on the system will have an adverse effect on human health. The norms indicated on the meters (optimal below 30 G/S units and acceptable to 50 G/S units) were determined by tests performed in Kazakhistan and standardized to their radiofrequency radiation standards established to prevent biological harm to the population. These meters are available from Stetzer Electric which can be reached by phone at (608) 989-2571 or at their website http://www.stetzerelectric.com/. Questions can be directed to firstname.lastname@example.org
Inverters used to convert DC to AC are usually extremely electrically polluting. Caution should be exercised in trying to filter them. It may be best done by the manufacturer. I have not yet heard of one that does not have extremely high readings on the Graham/Stetzer Microsurge meter a.k.a. Stetzerizer Meter.
Most off-grid systems have at least some portion of the system run off of an inverter. Inverters are usually HIGHLY electrically polluting. They usually pollute the entire system that is connected to them when they operate, likely including the DC system if the two systems are connected at all. (If this seems incredible to you, take a Graham/Stetzer Microsurge meter for DC systems and do measurements on such a system.) Several inverter systems measured have readings from 1500 G/S units to over 2000 G/S units. Thus, such an inverter cannot be part of a "clean" system unless sufficient filtering is possible. ALL grid-tie systems have inverters. Use a Graham/Stetzer Microsurge meter to see how it affects the power quality in a home with a grid-tie system. Turn the system on and off and see what the readings do.
On the bright side, a straight DC system can be highly efficient. Inverters can cost as much as 50% in efficiency. So going DC can nearly double the yield from the same solar panels.
In order to set up a "clean" DC system, it is imperative that you research EVERY component of the system. Most manufacturers are quite up front about any radiofrequency interference (RFI), signaling frequencies, electrical noise, or high frequency "sewage" that their device puts out or uses. In general, if a device has a "controller" instead of an on/off switch you will want to check into it. "Controller" can often mean that radiofrequency/high frequency signaling was used or that potentially polluting circuitry was used. When getting a motor-driven device, look for single speed motors, not motors with variable speed frequency drives. Also, look for brushless motors since they are generally "cleaner" than brush motors. Brushless motors are still not necessarily "clean". You can use either a Graham/Stetzer meter to check them or a handheld battery-operated AM radio - scan through the AM frequencies with the motor running. It is polluting if you hear static that is not present with the motor off. Avoid lights or other devices which use pulse width modulation or switching power supplies or other switching electronics.
Some common components that can be problematic:
Battery chargers are often highly electrically polluting. Both AC grid-based battery chargers and generator operated battery chargers often are highly electrically polluting. If absolutely necessary, a battery charger can be used, but, unless you can find a "clean" one, you should plan to not be around any wiring attached to the charger while the charging is occurring. It should be kept completely off and/or disconnected the rest of the time.
Charge controllers can also be highly polluting. Great care should be used in selecting a charge controller. Many charge controllers use pulse width modulation, another switching technology that results in electrical pollution. Some charge controllers do not employ this technology at all and others allow it to be turned off. The controller that we have found to be clean is made by Flexcharge and it is model NC25A-12(24,36,48). Their website is www.flexcharge.com. It does click on and off every thirty seconds or so when fully charged which would generate a transient, but otherwise it seems to be "clean".
Voltage converters can be highly polluting devices. Unless you can find a "clean" voltage converter, it is best to design your system to run at the voltage you will be using or use other methods of generating multiple voltage levels or using different voltage equipment e.g. connecting in series or tapping batteries differently.
Voltage switches can also be highly polluting due to the controller circuitry. If you need a voltage switch, Solar Converters makes a "clean" voltage switch that can be ordered from Solar Converters using VCS-1AH FET or VCS-1AL FET. The regular product can be found at (http://www.solarconverters.com/index.php/products/92-voltage-controlled-switch). It is the FET that tells them to make it clean. I believe it restricts what the switch can do, but it still operates as a voltage switch.
Back-up generators can be highly polluting. These are usually used for generating 60 Hz power for a house that loses power temporarily or to provide power to an AC device that is prohibitively far from the electrical grid. While most are quite electrically polluting, some are not. Be sure to use the Graham/Stetzer Microsurge meter to check the specific make and model you wish to purchase prior to making a purchase. The power quality varies greatly model to model.
For more information on DC solar systems, you may want to read "Photovoltaics Design and Installation Manual" by Solar Energy International. I highly recommend reading it before even contacting a professional so you are knowledgeable independently. Most professionals know little or nothing about the power quality issues inherent in an off-grid system. They can install a system; you will need to be sure it is "clean" enough for you to be healthy. One way to help with that is to have a minimal amount of wiring so that you are not so highly exposed to any pollution. Another way is to have the home wiring completely disconnected from the polluting and constantly live portion of the system. Then, only plug in the majority of the wiring in the evening when the lights are needed and unplug it again at night.
We have a 48 volt system powered by four 175 watt solar panels. We got a 48 volt system so that we could run the well-pump we needed. However, there are some distinct pluses to having a 48 volt system. For instance, the higher voltage allows us to make longer wire runs with smaller wire. We are able to use our existing wiring to power the LED lights throughout the house due to the higher voltage. The higher voltage has made some of the electronics conversions possible. For instance, the printer/fax/copier required 30 volts. It does, however, make it a bit more challenging to use the gizmos designed for 12 or 24 volt systems. Fortunately, we never had many gizmos. Also, small stand alone solar chargers can be used by those on and off-grid to charge battery operated electronics. They can be left in the sun to charge in areas away from humans and pets, to minimize exposure to the polluted electromagnetic fields that are likely to result. The system provides plenty of power for our needs during the vast majority of the year. We usually only have to charge briefly every few days.
Here are a few of the ways that we have maintained as normal a life as possible while going off-grid:
Refrigeration - We have a propane refrigerator. We had originally wanted to get a DC refrigerator and chest freezer, but discovered that the compressor being used at the time was highly polluting. We are enjoying our propane refrigerator. The only difference we find is that as ambient temperature changes on a seasonal basis, we have to adjust the temperature control. We are still without a large freezer for our home use.
Heat - We installed a gravity flow hot water system. Read How Come? Hydronics Heating Questions We've Been Asking For More Than 100 Years (with straight answers) by Dan Holohan to find out more. The book can be obtained through his website http://www.HeatingHelp.com. We used the overhead system as he describes with a few modifications. Modern modifications include: a closed system (no external oxygen exchange which prevents system oxidation) with a modern diaphragm pressure tank mounted off of the boiler, boiler operates off of a millivolt thermostat, with no minimum temperature requirement only a high temperature shut-off on the boiler, thus it only heats as much as necessary. We have found that the system heats much more evenly and efficiently than our forced air furnace had. Quiet too. Completely non-electric gravity flow boilers are still available, but a doctor's letter and proof of inability to have electricity may be necessary. We do not have the system permanently plugged into a water refill to avoid electrical current transfer from the water system. We fill with a hose. We have several dielectric unions in the gas line. We also have plastic line from the LP tank (a potential rf collector) to the house.
Lights - We have tried various LED possibilities. With the very low amperage LEDs draw and the higher voltage (48V) our existing wiring has been fine to use. This would not necessarily be true at lower voltages or higher amperages.
We have hooked two 24 volt LED automotive bulbs in series so we can run them on our 48 volt system. We use several pairs of these in a fixture. According to the manufacturer, at that time, the Dialight 586-4606-105F (28VDC) bulbs, and sister bulbs, did not use pulse width modulation. A base that converts the standard Edison base to the S-8 base, which these have, can be purchased from Kansas Windpower (http://www.KansasWindpower.net). It is item L450. Many of the lightbulbs available for purchase for home use do use pulse width modulation.
We have also used LEDs (C513A-WSN-CV0Y0151-ND from http://www.digikey.com/) connected securely with a good twist and some solder in series so that they add up to the correct voltage. We have set them up using a screw in base and baby food jar covers for ease of cleaning and to diffuse the light. We prefer to point the LED lights up at our white ceilings. We find that this diffuses the light well, resulting in a much more even distribution of light within the room.
Sump Pump - This was hard. Most bilge pumps (the solution originally recommended to me) are still brush motors and their capacity was too small. We finally settled on the pump from Wayne Pumps' 24 volt ESP-45 back-up pump system (http://waynepumps.com/index.cfm/product/56/esp45.cfm), as the best solution. It was part number 06710. We are still waiting to see how it holds up long-term since it is a back-up pump, but so far it works like a charm, doing a lot of pumping on not a lot of electricity. We have two hooked up in series and activated by the same float switch. It does require a bit of wiring work.
Well Pump - We got a powerful pump since we need to pump volumes of water at times. It is controlled by a pressure switch, no controller, which would have used high frequency signaling. It allows our system to continue functioning the same as it used to, including the pressure tank.
Solar System - We got help designing our system from the helpful folks at Backwoods Solar (http://www.backwoodssolar.com). They will not necessarily automatically design a "clean" system, but they were very obliging about providing phone numbers so I could ask the technical questions that I needed to and then re-designing the system with the answers in mind.
Electronics - We have successfully converted various electronics to run on our DC system. Most electronics are DC creatures anyway. The box at the end of the cord converts the AC to DC. It is usually highly polluting with a large electromagnetic field and uses electricity the whole time it is plugged in. (To conserve energy even on a utility system, unplug them or have them on a power strip that is turned off when not in use.) These converters usefully have what voltage DC the converter puts out so then it is a matter of having a knowledgeable professional remove the box and input the proper voltage from a DC system.
All the components we got (except lights) required additional electrical filtering to make them clean enough according to the reading from Graham/Stetzer Meter. (In spite of all the care I took in avoiding deliberate radiofrequency pollution, there was plenty of inadvertent electrical pollution to go around. Some levels were quite high.) In a pinch, the commercial Graham/Stetzer filters can be used on a DC system, however they can drain batteries so caution is required. In addition, 0.1 microfarad capacitors can be used to help filter the extremely high frequencies generated. I would recommend contacting Dave Stetzer to help design filters for your system. Stetzer Electric can be reached by phone at (608) 989-2571 or at their website http://www.stetzerelectric.com/. Questions can be directed to email@example.com
Good luck! If you have any questions please email me at: firstname.lastname@example.org
Click here for a printer friendly version