Install a mixture of alternative energy sources to disconnect from the electrical grid.
Alternative energy sources such as solar and wind power can supply enough electricity to replace the grid-connection of a home, as long as it is heated from non-electric sources. At the same time, switching to energy-efficient lighting and appliances means that you have to generate less power. A battery bank can cover those periods when it is dark and there is no wind, and a small emergency generator can be used to top up the batteries when the charge is low. Does this Spark an idea?
1. Decide on a heat source other than electricity, since you won’t be able to generate enough power to heat your home. Check for the availability of natural gas or look for a supplier of propane. Pellet stoves or wood furnaces and stoves are a more environmentally friendly alternative, but are more labor-intensive. Get a hot water heater that can use the same energy source as that used to heat the house.
2. Plan to reduce the power needed for lighting and other needs to a minimum. Plan to install LED lights and task-oriented lighting instead of general lighting. Look at reducing the cost of refrigeration by buying an energy-efficient refrigerator. Switch to gas or propane for cooking. Check the power used by every electric load in your home and see if it can be reduced by changing to another power source, or replacing it with a more efficient unit.
3. Make a list of all electric loads that you plan to supply from the off-grid system. Plan for a 12-volt DC system for LED lights and for some appliances that run on 12 volts, and that can be purchased from RV and trucking supply stores. List the 12-volt loads separately, and then list the loads that will require 120-volts AC. Add all the loads that might be used simultaneously to get the total peak load in watts that you will have to supply. For each load, estimate how long it will be used in a day and multiply the time in hours by the load in watts to get the kilowatt-hours used. Add all the kilowatt-hours to get a total.
4. Take the total watts calculated and purchase as many solar panels to contribute to the total as you can afford. If necessary, build your own panels from solar cells, following the solar cell manufacturer’s instructions, since solar power is costly but reliable and maintenance-free. Make sure you have enough solar power to supply the 12-volt DC loads.
5. Estimate the average wind speed at your location. Get a wind turbine generator that is rated to produce enough power at the average wind speed to reach your total power requirements, when the power is added to that produced by the solar panels.
6. Get batteries rated to supply the total requirements in kilowatt-hours for one day, as calculated earlier. As a rule of thumb, a typical lead-acid battery can supply one kilowatt-hour. Get a voltage controller rated for the power supplied by the solar cells. Get an inverter rated for the power required by the 120-volt AC loads. Wire the components together as per the instructions of the different manufacturers.
7. Add a small emergency generator to top up your batteries during extended periods of heavy cloud and no wind. Get a generator operating on natural gas or propane, if that’s the fuel you are using for heat. Get a generator rated for the minimum electric load you will need, typically your refrigerator, some lighting and a few other loads. Connect the emergency generator according to the manufacturer’s instructions.