It comes from coal, but here's what the company claims:

SILVERADO GREEN FUEL INC.

Silverado Gold Mines Ltd., (OTC BB: SLGLF) views new amendments to Regulation SHO; Final Rule as a positive outlook towards our listing on the OTC Bulletin Board.
Please read the full SHO rules here: http://sec.gov/rules/final/2007/34-56212.pdf

SILVERADO has been working six years with the head of its Green Fuel Division, Dr. Warrack Willson, who is an industry leader in the development of low-rank coal-water fuels (LRCWF). This fuel is made from hydrothermally treated low-rank coals (LRCs), sub-bituminous, lignitic, and brown coals. It is a low cost, non-toxic, non-hazardous and environmentally friendly substitute for petroleum derived fuels mainly in industrial and utility boilers, gasifiers, and other advanced combustors. Initial process economics indicate that LRCWF can be produced from any American LRC for under $15 per barrel, on an oil equivalent energy basis.

Silverado’s LRCWF (Green Fuel), so named due to its environmental friendliness, is an ideal candidate for use in high pressure liquid fed gasifiers, like the one developed by Texaco now being marketed by G.E. The product, synthesis gas, can then be converted by any one of a number of commercial Fischer Tropsch proc esses to yield a myriad of clean fuels and petrochemicals. The products are free of nitrogen, sulfur, particulate matter, and heavy metals and will find many applications, including aviation and auto gasoline, diesel, synthetic natural gas, naphtha, fertilizers, ammonia, urea, plastics and many others.

On April 9, 2007, Mississippi Governor Haley Barbour and Congressman Roger Wicker joined other state officials to kick off the Silverado Green Fuel Demonstration Project with a ground-breaking ceremony at the Red Hills EcoPlex site.

Silverado Green Fuel is a 100% wholly owned subsidiary of Silverado Gold Mines Ltd.

Source: http://www.silveradogreenfuel.com/