Methane formation potential of cup plant (Silphium perfoliatum)

• Published in: Biomass & bioenergy Vol. 75; pp. 126 - 133
• Main Authors: Haag, Nicola Leonard, Nägele, Hans-Joachim, Reiss, Klaus, Biertümpfel, Andrea, Oechsner, Hans
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2015
• Subjects: alternative crops; Biogas; Biogas yield; Biomass; corn; corn silage; crop rotation; Cup plant; dry matter accumulation; energy crops; Germany; grasses; laboratory experimentation; methane; methane production; plant breeding; Silphium perfoliatum; Specific methane yield; Germany; Biogas yield; Biogas; Specific methane yield; Biomass; Cup plant
• ISSN: 0961-9534; 1873-2909
• DOI: 10.1016/j.biombioe.2015.02.012

The growing number of biogas plants in Germany has greatly increased the demand for maize silage, the predominant crop used for biogas production. With a share of 80% among the energy crops, maize silage is currently subject to major concerns such as competition between food and fuel, environmental issues and sustainability. Alternative substrates cannot compete with the specific methane yield (SMY) of maize and are therefore disadvantaged. The cup plant is considered suitable to provide a solution however little data is available. To support the search for alternative crops, batch and continuous laboratory tests were carried out in order to determine the SMY of cup plant silage. The mean SMY in the batch test was measured at 0.251 ± 0.0141 m³N/kg oDM and at 0.227 ± 0.0158 m³N/kg oDM in the continuous test. The results show that the methane yield per ha of cup plant lies in the range between grass and maize silage. The cup plant proved to have no negative effects on process stability for the ratio fed into the digester. Although cup plant cannot currently compete with maize silage, further research in plant breeding will help to increase dry matter yields, SMY potential and promote the positive environmental effect such as a diverse energy crop rotation. •We examined the specific methane yield (SMY) potential of cup plant (Silphium perfoliatum).•Two lab scale digestion tests (batch and continuous) were used.•The mean SMY in the batch test was measured at 0.251 ± 0.0141 m³N/kg oDM.•The mean SMY in the continuous test was measured at 0.227 ± 0.0158 m3N/kg oDM.•Cup plant has no negative effects on the stability of the biogas process.