| dc.description.abstract | The Netherlands has set ambitious climate mitigation targets that call for de-carbonisation of the energy system. The resulting increase in decentralised solar power, together with the electrification of cars and heat supply, leads to high power loads on the distribution grid. The capacity of existing cables and transformers often falls short to cope with these power loads. A solution to ca-pacity shortages, could be the combined application of power-to-heat (P2H) and thermal energy storage (TES). With this solution, surplus solar power could be converted and stored as heat for later use, thereby relieving the pow-er grid. This research aims to assess the desirability of P2H combined with thermal energy storage in district heating networks, from a power grid per-spective. To this end, an energy system model is built to perform a techno-economic assessment for the neighbourhood of Eva-Lanxmeer in Culemborg.
Energy flows in the model are calculated from measured data, combined with standardized profiles and assumptions. A selection of applicable P2H and TES technologies and their techno-economic parameters are obtained from a litera-ture review. In total, 89 system configurations have been assessed that differ in terms of technology combinations, installed capacities and storage strate-gies. Electric boilers and heat pumps are considered as P2H technologies. Tank thermal energy storage (TTES), pit thermal energy storage (PTES) and bore-hole thermal energy storage (BTES) are considered as TES technologies. Three storage strategies are formulated, containing algorithms that determine how and when these technologies are operated. Storage strategy 1 aims to increase self-consumption, Storage strategy 2 aims to benefit from fluctuating electrici-ty prices and storage strategy 3 aims at reducing the power grid peak load. The outcomes of all system configurations are compared to the reference sys-tem, in which no power-to-heat and thermal energy storage is present and where capacity shortages are solved by investing in more grid capacity.
It is found that the combination of an electric boiler and PTES system with storage strategy 3 is most desirable. It has the potential to reduce power grid peak loads, while increasing solar power self-consumption and having a lower LCOH than the reference system. System configurations using strategy 1 can achieve even higher self-consumption and lower power grid peak loads but yield high LCOH’s. System configurations using strategy 2 are found to be un-desirable due to high costs and no additional benefits compared to the refer-ence system. Electric boilers outperform heat pumps in every system configu-ration by leading to higher self-consumption, lower power grid peak load and a higher LCOH. | |
