Wood gas excavator?

After watching the Geoff Lawton video showing earthworks. I have been thinking about earthworks on the cheep. I expect these excavators must use a lot of fuel. I found a source to get an excavators used. The shipping isn't as bad as you may think if your comparing to renting a machine or hiring a driver. Now the fuel issue needs to be solved. The three fuels I am thinking about on the farm are alcohol, biodiesel, and wood gas. I expect biodiesel would make the most sense but take the longest to accumulate. Wood gas would have some issues with the burner not always being level. I don't know if the fuel lines in a excavator could even use alcohol. Would wood gas even provide enough power?

You can do a diesel/woodgas hybrid--feed wood gas as the air supply and keep some diesel going to light it off and provide surge power.