A broad environmental impact analysis of local energy systems

Abstract

Nations face the need for a decarbonized energy supply, what goes along with the risk that they focus solely on reducing GHG emissions what may occur at the expense of other environmental impacts. Besides GHG emissions, the land requirement and the use of critical resources are considered as relevant in the context of renewable energy systems, as these environmental impacts will increase due to the shift from fossil fuels to renewable energy sources. For these three sustainability indicators, the impact is determined for the neighbourhood ‘Haven-Stad’, and discussed in relation to sustainable reference values. Also the trade-offs between the sustainability indicators were examined, as well as the effect of a different energy demand. Also the location of the environmental impact categories is researched, for a 100% renewable energy system in comparison to fossil fuel based energy systems.

The results have shown that that the shift from fossil fuels to renewable energy would decrease the GHG emissions of energy systems to levels where the consequences of global warming are manageable. Within renewable energy systems, an exclusive use of intermittent electricity sources is not recommended because it increases the need for energy storage what goes along with the use of critical elements, just as electricity production from intermittent energy sources by solar PV and wind turbines. Therefore, bioenergy could be implemented to provide for non-intermittent electricity, as long as it stays within the sustainable boundaries of land use. Bioenergy predominantly determines the global land use impact of renewable energy systems, while the use of (imported) biomass decreases the land use impact on the place where energy is consumed. This is an example of the externalization of environmental impact, caused by the shift from fossil fuels to renewable energy sources. Due to this externalization, the global impacts need to be taken into account more, and the dependency on countries with large reserves of critical resources increases. This affects the frequently mentioned benefit that renewable energy production increases the independency.

The global upscaling of EVs, battery grid-electricity storage and wind turbines may be hindered by resource depletion of lithium, neodymium and dysprosium. The global resources are sufficient to provide for the required amount of the metals, but it causes that relatively less is available for other applications of the metals than currently. Besides, the annual production of these metals need to increase to implement renewable energy systems on global scale before 2050.