Recently, I was asked how long our paraffin lamp oil will burn and found myself without a definitive answer. However, as I do enjoy being a know-it-all, I decided to go out to my "laboratory" and test for myself.
[caption id="attachment_1940" align="alignright" width="189"] My test subject.[/caption]
I took one of our copper oil lamps with a 1/8" round fiberglass wick and trimmed the lamp wick to about 1/8" long. I filled the lamp with 4 ounces of Firefly Pure Paraffin Oil and lit the little guy. After six hours, I snuffed the flame and re-measured the oil. There were three ounces left, which means (let me get my calculator) the oil burns at a rate of approximately one ounce every 6 hours. This means our 30 oz. bottle of oil will give you 180 hours of burn time, while our 128 oz bottle will give you a whopping 768 hours of light. With all those hurricanes swirling around out there, it's not a bad idea to invest in a nice oil lamp and stock up on fuel, just in case.
Now, admittedly, this was not the most scientific of studies, and there are a lot of variables that can impact your oil lamp burn time. The size of the wick, for example, can make a big difference - a large oil lamp with a 1/2" wick will draw (and burn) a lot more oil than a 1/4" or 1/8" wick. Also, the length of the wick sticking out can dramatically impact the efficiency of the lamp. If you have more than 1/8" of wick exposed, you'll be wasting fuel and making lots of unnecessary smoke. Also, by using a fiberglass wick instead of cotton, you'll improve your lamp's efficiency unless you are using an oil candle where cotton works work very well.
And of course, I can only speak for Firefly Paraffin Oil - other oils will burn differently, and from what I've seen, with more smoke. Please let me know your results if anyone else would like to answer the question "How long does an oil lamp burn with paraffin oil?"