A consequential LCA framework for smarter district heating decisions

As climate targets become more urgent, efficient decisions that reduce Greenhouse Gas (GHG) emissions become crucial. District heating (DH) is recognized as crucial to the decarbonization of Europe's energy system. Life Cycle Assessment (LCA) plays an important role in assessing the impacts of decisions. The use of LCAs on district heating is distinct from other domains as heating systems are highly local (city-level). When assessing decisions regarding heating, it is important to determine which technologies will react to the decisions to properly capture the associated impacts. Current LCA practices for heating grids overlook this factor. To address this, the authors propose a framework that identifies reacting technologies for DH grids based on location-specific characteristics and consequential LCA methodology, to assess the impact of different types of decisions, such as expanding the DH grid, installing new heating capacity, or decisions influencing heat consumption. The tool serves as both a complete LCA and a standalone Life Cycle Inventory (LCI) tool by presenting emissions and reacting mixes separately. Findings indicate that the mix of heating sources that respond to demand changes often differ from the current supply mix, affecting consumption-related impacts. This distinction is crucial for accurate GHG assessments, as modelling the existing supply mix instead of the reacting mix may result in burden-shifting within the grid, undermining efficient GHG reductions.