Applying Harmonised Geothermal Life Cycle Assessment Guidelines to the Rittershoffen Geothermal Heat Plant

Abstract

Heat production from a geothermal energy source is gaining increasing attention due to its potential contribution to the decarbonization of the European energy sector. Obtaining representative results of the environmental performances of geothermal systems and comparing them with other renewables is of utmost importance in order to ensure an effective energy transition as targeted by Europe. This work presents the outputs of a Life Cycle Assessment (LCA) performed on the Rittershoffen geothermal heat plant applying guidelines that were developed within the H2020 GEOENVI project. The production of 1 kWhth from the Rittershoffen heat plant was compared to the heat produced from natural gas in Europe. Geothermal heat production performed better than the average heat production in climate change and resource use, fossil categories. The LCA identified the electricity consumption during the operation and maintenance phase as a hot spot for several impact categories. A prospective scenario analysis was therefore performed to assess the evolution of the environmental performances of the Rittershoffen heat plant associated with the future French electricity mixes. The increase of renewable energy shares in the future French electricity mix caused the impact on specific categories (e.g., land use and mineral and metals resource depletion) to grow over the years. However, an overall reduction of the environmental impacts of the Rittershoffen heat plant was observed.

Deep geothermal energy extraction, a review on environmental hotspots with focus on geo-technical site conditions

“…Two studies considered a lifetime of 25 years based on the expected lifetime of the real plant investigated [24] or without providing further information [31]. By contrast, [25] used a lifetime of 30 years, derived from the plant's feasibility analysis, [29] did so without providing further information and [30] did so based on the GEOENVI guidelines [13].…”

“…We also added water consumption (WC) impact as well. The WC impact was calculated by 7 studies [15,26,28,30,32,34,37] and is considered to be of high importance for regions facing water scarcity [10]. The impact results are considered when reported in the, most frequently used, units presented in Table 2.…”

Environmental and Socio-Economic Impact of Deep Geothermal Energy, an Upper Rhine Graben Perspective

“…Environmental and Socio-Economic Impact of Deep Geothermal Energy, an Upper Rhine… DOI: http://dx.doi.org/10.5772/intechopen.107395 which provided recommendations to harmonize methodological choices in each of the four steps of LCA [40]. Environmental performances per kWh of heat of the Rittershoffen geothermal plant were published by [41] and compared to at the production of 1kWh of heat with natural gas. Results of this study are presented in Figure 4.…”

“…Figure 4.Comparison between the production of 1 kWh of heat from natural gas and from the Rittershoffen geothermal plant for different impact categories: Acidification (ACI), climate change (CC), freshwater ecotoxicity (Eto), marine eutrophication (Eum), freshwater eutrophication (Euf), terrestrial eutrophication (Eut), human toxicity-cancer (HTC), human toxicity-non-cancer (HTN), ionizing radiation-human health (IR), land use (Lnd), ozone depletion (ODP), particulate matter (PM), photochemical ozone formation-human health (POz), resource use-fossils (REn), resource use-minerals and metals (RMi), and water use (wat). From ref [41]…”

Assessment of deep geothermal research and development in the Upper Rhine Graben

“…In order to achieve this goal, a rapid reduction of greenhouse emissions is inevitable. Geothermal energy can make an important contribution, since greenhouse gas emissions per unit of energy are one to two orders of magnitude smaller than for fossil fuels (Lacirignola and Blanc 2013;Douziech et al 2021). In recent years, the share of renewable energy forms in Germany's electricity production has increased to over 50% in 2020, mainly due to the expansion of wind and solar energy (Frauenhofer ISE 2021).…”