• Energy Research

Abstract Balkan countries in the process of joining the European Union shall adopt greenhouse gas emissions reduction targets and implement appropriate mitigation policies and measures. This paper presents a simplified methodological framework based on marginal abatement cost curves for estimating the technical and economic mitigation potential at sectoral level (buildings and road transport) in selected Balkan countries. The results of the analysis provide to decision makers useful information regarding the availability of background data, the potential for setting ambitious mitigation targets, and detailed tools for assisting the selection of policies and measures to meet these targets. The analysis performed shows that a significant part of the greenhouse gas emissions abatement potential can be achieved through win–win measures. The incorporation of environmental externalities associated with these interventions, estimated through benefits transfer, further improves the economic performance of these measures, especially in the buildings sector. Moreover, the implementation of these measures is shown to result in positive macroeconomic effects through increases in GDP (gross domestic product) and creation of new jobs. Finally, the rebound effect may restrict the estimated greenhouse gas emission reductions in the buildings of the countries examined due to the low energy performance of the existing building stock.

The establishment of tree plantations in rural areas in Uganda could provide renewable energy to rural communities, while decreasing greenhouse gas emissions from conventional electricity sources and unsustainable forest use. The study evaluates the greenhouse gas benefits that could be produced by biomass based energy systems in Anaka, a rural settlement in the Amuru district in northern Uganda. Two alternative energy uses are explored: a) electricity production through wood gasification and b) traditional fuelwood use. It is estimated that a small-scale wood gasifier could provide electricity for basic community services by planting less than 10 ha of new short rotation coppices (SRCs). The gasification system could save 50–67% of the GHG emissions produced by traditional diesel based electricity generators in terms of CO2-eq. (0.61–0.83 t MWh−1 or 7.1 t y−1 per hectare of SRCs). It was also estimated that traditional use of fuelwood in households is currently unsustainable, i.e. the consumption of wood is higher than the annual growth from natural wood resources in the study area. It is estimated that 0.02–0.06 ha per capita of plantations could render the current consumption of wood sustainable. In this way, the CO2 emissions produced through unsustainable extraction of wood could be avoided (2.0–7.3 t per capita per year or 50–130 t y−1 per hectare of SRCs).

The goal to decrease greenhouse gas (GHG) emissions is spurring interest in renewable energy systems from time-varying sources (e.g., photovoltaics, wind) and these can require batteries to help load balancing. However, the batteries themselves add additional GHG emissions to the electricity system in all its life cycle phases. This article begins by investigating the GHG emissions for the manufacturing of two stationary lithium-ion batteries, comparing production in Europe, US and China. Next, we analyze how the installation and operation of these batteries change the GHG emissions of the electricity supply in two pilot sites. Life cycle assessment is used for GHG emissions calculation. The regional comparison on GHG emissions of battery manufacturing shows that primary aluminum, cathode paste and battery cell production are the principal components of the GHG emissions of battery manufacturing. Regional variations are linked mainly to high grid electricity demand and regional changes in the electricity mixes, resulting in base values of 77 kg CO2-eq/kWh to 153 kg CO2-eq/kWh battery capacity. The assessment of two pilot sites shows that the implementation of batteries can lead to GHG emission savings of up to 77%, if their operation enables an increase in renewable energy sources in the electricity system.

The greenhouse gas (GHG) emissions, expressed in carbon dioxide equivalents (CO2-eq), of different Austrian biogas systems were analyzed and evaluated using life-cycle assessment (LCA) as part of a national project. Six commercial biogas plants were investigated and the analysis included the complete process chain: viz., the production and collection of substrates, the fermentation of the substrates in the biogas plant, the upgrading of biogas to biomethane (if applicable) and the use of the biogas or biomethane for heat and electricity or as transportation fuel. Furthermore, the LCA included the GHG emissions of construction, operation and dismantling of the major components involved in the process chain, as well as the use of by-products (e.g. fermentation residues used as fertilizers). All of the biogas systems reduced GHG emissions (in CO2-eq) compared with fossil reference systems. The potential for GHG reduction of the individual biogas systems varied between 60% and 100%. Type of feedstock and its reference use, agricultural practices, coverage of storage tanks for fermentation residues, methane leakage at the combined heat and power plant unit and the proportion of energy used as heat were identified as key factors influencing the GHG emissions of anaerobic digestion processes.

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