A Techno-Economic Case Study of the Implementation of Hydrogen Technology in Connection to a CHP Plant

Sammanfattning: With climate change as the main driving force, the energy system is currently undergoing changes. Both the share of renewable resources used to produce electricity and the overall electrification is increasing. A way to handle the resulting challenges from more intermittent electricity production is by the implementation hydrogen technology. Hydrogen technology can help balance the electricity network both by operating after spot price and by providing ancillary services. This thesis investigates the techno-economic potential of the implementation of a hydrogen system with Örtofta combined heat and power (CHP) plant. More specifically, utilization of residual heat in the district heating network and the contribution of ancillary services are examined. Two hydrogen systems are investigated, a power to gas (P2G) system and a complete hydrogen system (Hydrogen System). Hydrogen is sold from the P2G system whereas electricity is sold from the Hydrogen System. Both systems include a PEM electrolyzer, a compressor and a pressurized storage tank. A PEM fuel cell is also included in the Hydrogen System. A comparative literature review was used to choose the suitable technologies. Furthermore, the systems are modeled in Energy Optima 3, a software that optimizes production plans. Optimizations are performed on historical data between October 2021 and October 2022. The method consists of two main models, the Base Model and the Balance Model. In the Base Model, operation of the hydrogen system in connection to Örtofta CHP plant, when only trading on the spot market, is investigated. In the Balance Model, the hydrogen system's contribution with ancillary services is investigated. The results show a Payback time of 2.86 to 3.06 years for the Hydrogen System and 2.15 to 2.39 years for the P2G system. Important to note is that the investment costs in the calculation only include the cost of the actual units, i.e. the surrounding investment costs are excluded. Moreover, with the implementation of the Hydrogen System the profit between October 2021 and October 2022 is increased by 19.9 to 21.2 percent, compared to a reference scenario without hydrogen technology at Örtofta. The increased profit for the P2G system during the same period is 13.4 to 14.8 percent. For both systems, the majority of the profit was earned from the participation on the balancing markets. The overall conclusion from the thesis is that, with the utilization of residual heat and the contribution with ancillary services, hydrogen technology in integration with Örtofta CHP plant shows both technical and economical potential.