Paper Conference

Proceedings of uSim Conference 2020: 2nd uSim Conference of IBPSA-Scotland


Including building energy flexibility as an asset in system-wide district heating optimization models

Steffen Petersen, Rasmus Elbæk Hedegaard, Janus Tougaard, Tommy Mølbak

Abstract: The ratio of renewable electricity production is currently increasing which introduces an increased need for energy storage and flexibility. One solution for accommodating this need is an increased interconnection between district heating (DH) systems and the electricity grid; if orchestrated right, DH systems can act as a ‘buffer’ by converting excess renewable electricity production into heat and store this in the thermal mass of the DH system, leading to a reduced energy need during times where renewable production is scarce. In this paper, we propose a new methodology of including the utilisation of the thermal mass of buildings as a potential asset in a technoeconomic optimization. The methodology relies on clustering techniques to condense a bottom-up representation of the buildings in an area to a highly reduced number of archetype models, thus significantly reducing the computational burden associated with including the energy flexibility potential of groups of buildings as an asset in techno-economic optimization problems. In an urban expansion/densification case study, we demonstrate the accuracy of the archetype representation and include the building models in a techno-economic optimization to investigate whether energy-flexible buildings have an impact on the optimal investment strategy. The results indicate that energyflexible buildings may reduce the amount of additional production capacity required for urban expansion/densification – in this case, 8% of the total peak production. The total savings of including energyflexible buildings is probably not sufficient for a viable investment; however, future studies should capitalise other system benefits before any sound conclusion on the viability of energy-flexible buildings can be made.
Pages: 148 - 155