Ecodesign of Biomethane Production and Supply System
2017
Māra Rēpele

Defending
08.06.2017. 14:00, Rīgas Tehniskās universitātes Enerģētikas un elektrotehnikas fakultātē, Āzenes ielā 12/1, 115. auditorijā

Supervisor
Gatis Bažbauers

Reviewers
Ritvars Sudārs, Francesco Romagnoli, Visvaldas Varžinskas

The aim of this Doctoral Thesis is to perform an eco-design of the biomethane production and supply system, to reduce environmental impact caused by the natural gas-using industrial processes and to promote the use of renewable energy sources in Latvia’s energy supply system. To reach the objective of the Thesis, such a tasks were set: - To characterize environmental impact of building material in order to identify the life cycle stages and processes which create the most significant environmental impacts. - To evaluate environmental aspects of renewable energy alternatives for replacement of natural gas, via life-cycle analysis. - Perform life-cycle analysis, and technical and economic assessment of the biomethane production and supply system. - To create a model, with the assistance of which it would be possible to devise policy to support biomethane production and supply and to perform a scenario analysis to determine the optimal solution for the support mechanism. Structure of the Thesis. Introduction: novelty and topicality of the research is emphasized in this chapter; as well as objective of the study is defined and tasks are set; and the vision of the significance of renewable energy sources in the future is decribed. First chapter: life-cycle analysis of plant, which uses natural gas as a fuel, was carried out; calculations were made and production stage which generates the greatest environmental impact was identified; and solutions for improvement were defined. Life-cycle analysis was performed using SimaPro software and ReCiPe impact assessment method. The calculation results shows, that the environmental impact caused due to the use of natural gas, is more than 75% of the total environmental impact of production. Second chapter: an evaluation of environmental impact of renewable energy alternatives for replacement of natural gas was carried out using GEMIS database and SimaPro software, and ReCiPe impact assessment method. Environmental performance of biosythetic natural gas, biomethane, the first and the second-generation biofuel, and natural gas was compared. The results indicate, that the most significant reduction in environmental impact could be achieved, if natural gas is substituted by biomethane. Third chapter: results of the life-cycle analysis and economic assessment of the biomethane supply system were described. The environmental impact of biomethane transportation, including connection to grid, was assessed, and the costs of biomethane produced and injected into the grid were calculated. Results of the life-cycle analysis show that the gas supply infrastructure is an important factor that should be taken into account when biomethane production and supply systems are panned and installed. The results also indicate that the biomethane production and supply shall be supported finacially, if it is to be competitive with the price of natural gas. Fourth chapter: the experience of European countries of the implementation and use of renewable energy support mechanisms is desribed. And a system dynamic model for the biomethane production and supply support mechanism was developed, which has been tested for conditions in Latvian. Risk assessment with sensitivity analysis for different scenarios was conducted. Results of the sensitivity analysis show, that in spite changes of the main factors, it is possible to get results with a relatively small dispersion when using the development system 5 dynamic model. Therefore, it can be assumed that the developed system dynamic model can be considered plausible and applicable to create and analyze the biomethane production and supply support mechanism. Conclusions: the key results of the study are highlighted and answers to the study objective and tasks are provided. The list of references with a bibliographic description is included.


Keywords
Ekodizains, biometāns, sistēmdinamikas modelēšana, atjaunojamie energoresursi, ilgtspējīga energoapgāde

Rēpele, Māra. Ecodesign of Biomethane Production and Supply System. PhD Thesis. Rīga: [RTU], 2017. 166 p.

Publication language
Latvian (lv)
The Scientific Library of the Riga Technical University.
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