1. Bioenergy (Is bio sustainable?)
Energy plant of the future?
Hardly anyone here in Germany knows the cup plant (Silphium perfoliatum). It stems from North America, yields almost as much biogas as corn, but has many advantages compared with maize monocultures.
In its first year, the cup plant is only a small rosette that does not yield any crop. But the plant can reach an age of 10 to 15 years and grows up to three meters (ca. 10 feet) high from the second year onwards. Every autumn, it supplies a corresponding amount of biomass for the production of biogas.
A big advantage compared to maize: even in winter it covers the ground and its deep root system helps soil cohesion, even on slopes. In addition, the cup plant does not require fertilization or crop protection from the second year onwards and copes well with poor soils.
The problematic leaching of nitrogen (as nitrate) into the groundwater thus hardly arises. And if the cup plant is not fertilized, laughing gas (nitrous oxide) should also not form in the ground.
Literature and Links:
- Umweltbundesamt 2017: Übersicht zur Entwicklung der energiebedingten Emissionen und Brennstoffeinsätze in Deutschland 1990 – 2015. S. 4,
- Frauenhofer ISE (2017): Aktuelle Fakten zur Photovoltaik in Deutschland. Fassung vom 21.10.2017. www.pv-fakten.de. S. 41
The panel for download as pdf (1.261 MB)