**rancid olive oil burns more efficiently, so dont throw it out* Make Your Own Olive Oil Candles. Olive oil burns clean and doesnt smoke. You can make these lanterns in any size of jar that you have on hand. Also, if you want them to be scented, you could add essential oils (or even dried or fresh herbs!) right to the oil. Little House On The Prairie Living
"This option is small-scale and it is built around a reclaimed heat dispersal system from an old refrigerator (which you can get with the gas removed from your local dump). It has no pump as it is gravity fed and it requires no electricity to work. Just put it in the sun, turn on the water feed and you will get a slow but constant supply of very hot water..."