Mr Switchgrass is an inverted downdraft gasifier design that burns/gasifiers chopped switchgrass or weeds with little to no smoke problems. A rule of thumb is that each section will burn for a solid ten minutes at full flame. I measured 66 lbs for one load and it ran for about 40 to 50 minutes.
"Manufactured Gas In The Home", a historic document (1925) digitally remastered by Puffergas. The author, Samuel Wyer, wrights about distribution, economics, correct gas use, consumers and more.
One of the first Historic Documents by Puffergas is the "Pederick Owner's Manual", digitally remastered. This is an owners manual for a 1942 charcaol gasifier used to fuel cars and trucks. Shows the gasifier and filters, also explains each.
The above equation tells us that with steam and hot or molten iron we can make H2 with rust being the byproduct. This rust can be converted back to iron. Check out the below links for more information.