Waste veggie oil lamps & candles for when the lights go out. Found this today on a survival blog, thought I would pass it along:
"Raw animal fat can quickly become rancid. Therefore raw animal fat should not be saved and then converted into grease at some future date. The best procedure is to render animal fat into grease while the fat is still fresh. Rendered animal fat has a much longer storage life than raw animal fat.)"
How to Clarify Bacon Grease (pork lard), Hamburger Grease (beef tallow), and Other Types of Used Cooking Grease, Oil, and Drippings
Measure the amount of used cooking grease (or used cooking oil) and put it into a cook pot. Add an equal amount of water to the cook pot. Measure another one-half the original amount of water and set it aside for later. Add one tablespoon of salt to the cook pot. Bring the mixture to a boil inside the pot. Turn off the heat. Then gradually pour the cold water you previously set aside into the hot mixture.
The mixture will begin to separate into three layers as follows:
1. pure fat on top, 2. fat mixed with impurities in the middle, and 3. water on the bottom.
Carefully ladle the top layer of pure fat into a clean container and save it for future use. Discard the bottom two layers. Label the container with the type of grease that it contains (pork lard, beef tallow, cooking oil, etc.)
Softer fats, like lard, can be used in 'fat lamps' or "button lamps". Basically a fat lamp is a shallow container holding soft fat and a wick held in it or draped over the side. A button lamp is the same only a metal button or even a large washer is wrapped with some sort of wicking material, tied with a wire so that the corners stick up and the material is allowed to soak up the fat and then lit.
Here are a couple of sites to look at if you are interested
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