Biogas generation opens new possibilities for the use of legume growths and thus for legume cropping, as quality restrictions are lower than for other forms of utilization. The German example of energy cropping shows the possibility of up to 20% of forage legume integration for bioenergy production into the cropping systems. This can allow an improvement of sustainability and resilience, especially with regard to reduced external inputs, improved humus, energy and nutrient balances, reduced greenhouse gas emissions, and the general positive impact of forage and intercrop legumes on cropping systems.

One hectare of main crop forage legumes delivers the energy for the operation of 12–17 ha of arable land. Crop residues and intercrop legumes mean additional energy yield.

For organic cropping systems, the anaerobic digestion of forage legumes allows higher nitrogen efficiency combined with reduced greenhouse gas emissions and reduced nitrate leaching risk. The higher N-efficiency results in higher yields and higher raw protein contents of nonlegume crops in crop rotations.

Without regarding the additional positive impacts, forage legumes as energy crops are only competitive under special conditions (e.g., cultivation on marginal sites). Economic internalization of positive external effects would promise legume cropping for this issue. For the further bioeconomy, the legume-based green biorefineries can deliver energy, colors (e.g., based on chlorophyll and carotins), vitamins, proteins, fibers, fatty acids, etc. In this way, forage legumes can get (again) key elements of sustainable economies.