Most maize is used as silage for animal feed, especially for dairy cattle, but increasingly maize is being grown as an energy crop for anaerobic digesters (AD) that are subsidized from public money to produce gas for fuel. … Because it is the most readily grown bulk product it has become the core feedstock for AD plants.
Benefits include Higher crop productivity. Decreased use of water, fertilizer, and pesticides, which in turn keeps food prices down. Reduced impact on natural ecosystems.