Dace Lauka

Sustainable Use Of Macro-Algae For Biogas Production In Latvian Conditions: A Preliminary Study Through An Integrated Mca And Lca Approach

Abstract The study focuses on sustainability evaluation of an algae-based energy system in Latvia with a holistic and integrated approach of multi-criteria analysis combined with life cycle assessment (including a practical side - biogas yield experiments of locally available algae). The study shows potential for sustainable use of algae in Latvian conditions and thus that algal biomass can be utilized for the production of biogas. The most sustainable and feasible scenario of using algae for biogas energy production foresees the collection of algae biomass from natural water bodies. Important beneficial effects through the use of algae are related to avoiding global warming potential (GWP) and eutrophication impacts. Biogas batch experiments carried out with the local macrophyte C.demersum have shown a methane yield of 554 l CH4/kg VS.

Heat Pumps Integration Trends in District Heating Networks of the Baltic States

Climate change considerations stimulate to switch to wider use of renewable energy sources for electricity generation. However in case of solar and wind energy, the use is burdened with non-regular generation trends. Electricity storage technologies, for example heat pumps, are observed as a potential technology to solve the non-regularity issue of the renewable electricity generation, reduction of fossil fuel generated greenhouse gas emissions and increasing the share of renewables in energy production sector. The process of heat pumps integration in district heating system can differ for each heating and electricity production and distribution system.Energy systems behaviour types plays significant role while performing an integration efficiency analysis. The present paper analyses the possibilities of integration of heat pumps in district heating systems of Latvia, Estonia and Lithuania as a tool for accumulation of renewable resources generated electricity.