Algae Use Evaluation for Biogas Production in Latvia

In order to meet the growing demand of energy resources, alternative resources are needed to replace and supplement the use of fossil fuels. The limited fossil resources and their impact on climate change are a topic of discussion not only among scientists, but world leaders as well. While the discussions are still on-going European Union is taking action by setting targets for year 2020 and year 2030 for climate and energy sectors. The aim is to increase the share of renewable resources up to 20 % and 40 % respectively. In order to meet these targets, the existing renewable energy resources need to be supported and their use expanded as well as new resources need to be researched and supported.

The Sustainable Development Strategy of Latvia 2030 and Latvian Bioeconomy Strategy 2030 highlights the need for a more sustainable use of local, available nature resources, also mentioning that washed-out marine algae are one of the least used local resources. Even though the algae research is a topical field, there is no evaluation methodology for determining the algae use potential for biogas production that would take into account energetic, environmental and economic aspects together.

Based on the EU targets for climate and energy sectors and Latvian strategies on how to reach those targets, the author of this thesis sets an aim to develop and test a methodology for evaluating algae use for biogas production taking into account three main aspects – energetic (experimental determination of energetic values), environmental (Life Cycle Assessment) and economic (Life Cycle Cost Analysis). The methodology development is based on a case study of locally available algae species in Latvia.

The basis of thesis is 7 thematically unified peer-reviewed scientific publications that are published in different scientific journals, available at different scientific information storages and international databases. The aim of these publications is to transfer and approbate the evaluation methodology. The thesis consists of introduction and four chapters.

Introduction defines the aim and tasks of the study, describes the structure of study and the methods used as well gives information about the approbation of the study. The first chapter contains the literature review. The second chapter contains the methodology development description as well as methods used within descriptions. The third chapter contains case study description. The fourth chapter describes the results of the case study, as well as contains the testing and evaluation of the methodology itself. The conclusions are summarized at the end of the thesis.