A silly and fun demonstration of biomass was on a British car program called Top Gear proved that you could power cars with cow droppings.
In principle biomass can provide an all-purpose fuel, but it has drawbacks. It still requires burning organic material which produces CO2and soot. Because you can grow the fuel it is more carbon neutral than fossil fuels. Like fossil fuels, the amount of energy it can produce is proportional to the amount of fuel to burn. Biomass also has the down side that it has to be dried before it can be used, which can take a lot of energy, and it has a more complicated and varied structure compared to fossil fuels.