The following is an excellent introduction and explanation of using gasification for energy generation. Its been around for many years.
The company that put the information on their website have many commercial units for sale.
I hope you find this as interesting and informative as I did.
Its is easy to build these rigs at home, i know Tommy Reed and many others have had experience in this area.
http://revolution-green.com/small-scale-gasification-solution/
Kind Regards
Mark