Originally Posted by martinw  Dear Geof,
This will be a problem. Although larger diesel fuel tanks tend to have heaters these days ( those smart engineers have anticipated "Global Cooling" ), what is going to power them?
My guess..grid-supply nuclear power.
Best wishes,
Martin |
Allopw me to be pedantic; after all I do it so well.
(I should comment my only failing is overweaning modesty)
The term 'biodiesel' is thrown around rather loosely.
It is possible to run a diesel engine on straight cooking oil, fat, drippings, whatever you cal it; provided you keep whatever it is above its melting point...and filter out the fragments of French Fries.
But you have to keep things warm; over here you can buy kits that heat a supplementary fuel tank and the fuel lines to make this possible. However, you still have to start on straight diesel and switch to straight diesel before shutting the engine down.
This is because the cooking oil/fat is a triglyceride that has tends to solidify at around room temp. If you don't know what a triglyceride is, tough.
It is possible to take waste cooking oil and do a trans-esterification reaction to turn it into, more or less, the same structure as regular diesel oil.
Regarding the heaters on large diesel fuel tanks; the 'smart engineers' are also smart economists. Diesel comes in many flavours, for vehicle fuel that will be used at low temperatures the preferred flavor has a low paraffin content; paraffins are waxes that solidify at 0 C or below. This means that high paraffin diesel does not have much market for vehicle fuel and is available at a lower cost; if you install heated tanks you can utilize a cheaper fuel.
And what will fuel the heaters? Well, even with the most efficient diesel installation 60% of your energy is lost as heat; more than enough to keep your fuel tanks warm. More than enough to heat all the surrounding buildings if things were designed correctly.