Emma Lindkvist

Biogas production also yields digestate, which can be used as biofertilizer. Using the digestate allows for the recycling of nitrogen and phosphorus back into farmland. The biogas produced can be used to generate heat and electricity, or upgraded to natural gas quality and then injected into the natural gas grid or used as vehicle fuel.

In my research, I study biogas production from various systemic perspectives. Among other things, I have examined whether the production and use of biogas at a food processing facility is more profitable if it takes place on-site at the facility rather than at an external biogas plant. This was also analyzed from an environmental perspective. The results showed that it is better—from both an economic and an environmental perspective—to produce biogas on-site at food processing facilities and to use that biogas on-site.

Management of Organic Byproducts

Another project involves studying how organic byproducts (waste) from various food industries should be managed. Currently, much of this organic waste is used in animal feed production, composted, or incinerated at waste-to-energy plants. In this study, I examine whether the alternative of using the waste for biogas production is better from an economic, energy, and environmental perspective. I also look at how the system’s performance changes if the biogas produced is used to generate electricity and heat or is upgraded to vehicle fuel.

Energy Audits at Biogas Plants

I have also helped develop a method for conducting energy audits at biogas plants. Among other things, the method outlines how to break down the various processes at the plant when presenting the energy audit results—both to gain a clearer picture of the individual plant and to enable comparisons between different plants.Being able to compare biogas plants with one another—both within Sweden and abroad—can be valuable when it comes to knowledge transfer. The terms used to describe biogas plants in Sweden do not correspond to those used in other European countries, which can lead to misunderstandings and missed opportunities for sharing experiences.With a common terminology—at least within Europe—it would be easier for researchers and professionals in the biogas industry to compare biogas plants in different countries and thereby increase the exchange of knowledge. A first step toward this has been taken, as we have developed a framework for categorizing biogas plants. The next step will be to propose a common terminology.

Teaching

I teach several courses offered as part of the Bachelor of Science in Energy, Environment, and Management program and the Master’s program in Sustainability Engineering and Management.