Biomass
Energy from biomass is generated by combustion, gasification or fermentation of organic materials, such as wood, kitchen and garden waste, as well as vegetable oil, manure and (parts of) crops grown specifically for this purpose.
Biomass, unlike fossil fuels, does not run out and is therefore sustainable. Burning wood in a stove is also a form of bioenergy. This is just not always clean.
The largest bio-digester in Limburg is in Leudal. There, a digester uses manure and other organic materials to generate biogas. This biogas is used to generate electricity but you can also run a car on it.