Energy Conversion
[an error occurred while processing this directive]Last Updated 2/12/2003
Overview
Every time energy is converted from one form to another, usable energy is lost to such things as unwanted heat and light, so it makes sense to minimize the number of conversions that take place.
Types of Energy Conversion
Generators - These are really inefficient (~15%)ways to convert fuel to electricity.
Fuel Cells - These are relatively efficient ways to convert fuels to electricity. A battery storage system and Inverter will still be necessary.
Inverters - These are fairly efficient (~92%)ways of converting electrical energy stored in batteries into 120VAC power, but if you can power the device directly from the 12V battery, do that instead.
Burning Fuels for Heat - Portable propane heaters and wood stoves lose about 20% of the heat energy produced through the vent, making them about 80% efficient. Central heat-type heaters are about 95% efficient.
Burning Fuels for transportation - This is a really inefficient (~15%) way to use the fuel.
Minimizing Energy Conversions during an Emergency
Communications equipment (computer/TV/telephone), Security Systems, Energy efficient electrical lighting and refrigeration are legitimate uses for electricity during an emergency. Find some other way to do everything else. Microwave ovens and the George Foreman grill can be replaced by a $40 Coleman Propane stove. Electric heaters can be replaced with propane heaters if ventilation is possible.
If your primary source for electricity in an emergency is a generator, take steps to minimize electrical energy requirements, then run every electrical device possible from 12VDC. Minimize the number of energy conversions when charging batteries. Don't convert energy from 12VDC to 120VAC then plug in the cell phone charger if it's possible to charge the battery using a car charge cord.
If your primary source of electricity in an emergency is a generator, take steps to minimize electrical energy requirements, then take steps to get the most efficient 120VAC devices possible, then run everything possible directly from 120VAC.