As our environment struggles and global warming occurs, scientists are always looking for new ways to generate energy. One of those methods is biogas production, a valuable technology that has been around for a while now. Through biogas production, energy can be constantly produced by a large amount of organic raw materials, such as manure, catch crops, energy crops, sewage sludge, and plant residues. Thanks to a new study, we may know how to increase the production of biogas in order to help the planet thrive.
Biogas production presents a large advantage over other renewable energy sources like wind and solar energy, because through biogas production, energy can be produced at the constant rate. Wind and solar energy, on the other hand, depend on the wind or sun for production. Germany has about 8,000 biogas plants installed throughout the country. This generates an electricity output of around 4,500 megawatts. In fact, around seven percent of Germany’s energy is currently generated from biomass. It is hoped that even more biogas can be produced in the future in order to keep our planet healthy.
Scientists from the Helmholtz Centre for Environmental Research (UFZ), the Deutsches Biomasseforschungszentrum (DBFZ), and the University of Aarhus (Denmark) have made some further strides in the world of biogas production research. These researchers were able to increase the produce of methane by up to 14 percent within laboratory conditions. This is a huge accomplishment because methane is the most valuable component of biogas. Scientists achieved this by adding a substrate to a fermentation tank at intervals of one to two days. This was different from the typical interval of every two hours. It was shocking to find that feeding the reactor with less frequency led to a greater energy yield.
The researchers went about the study by feeding two 15-liter reactors with distiller’s dried grains with solubles (DDGS). The reactor were fed under the same exact conditions for a period of nearly four months. Distiller’s dried grains with solubles (DDGS) is a byproduct of a process called bioethanol production utilizing starchy grains. For this research, one reactor was fed DDGS every two hours, while the other reactor was fed with the entire quantity once a day. In another experiment, the second reactor was fed once every other day, which the first one was kept at once every two hours.
The results found the feeding the full quantity of biomass into the fermentation tank once a day, as opposed to feeding it in two hour intervals, led to the production of 14 percent more methane and 6 percent more total biogas. If the tank was fed every two days, 13 percent more methane was produced and 18 percent more biogas was produced.
This was a surprising result. One explanation would that the greater variations in environmental conditions, such as the fluctuating substrate concentration, led to an increased diversity within the microbial community. This could have caused more functional groups of bacteria, meaning that the microorganisms would have more ways to degrade the substrate with more efficiency.
The researchers used T-RFLP profiles of the micro-organisms in order to prove that this approach has no negative effect of the stability of the process of biogas production. These profiles verify the genetic fingerprint of the community of bacteria and methanogenic archaea that changes the organic material into biogas.
This is just beginning of researching the flexibility of biogas production by managing the frequency of feeding. The results in the study have inspired the UFZ researchers to delve deeper. The next step will be confirming the results by performing trials in larger reactors. The idea of using other substrates has also been considered for future research.
Scientists are working towards the optimal way to produce a much biogas as possible. The more biogas we produce, the more access we have to energy that can be consistently produced regardless of sun, wind, or other environmental factors. This revolutionary research will bring us toward a more environmentally friendly tomorrow.