Energy system transitions pathways with the new H2RES model: A comparison with existing planning tool

Anthropogenically caused climate change is amongst the main problems that society faces today. To limit the increase in average global surface temperature, several countries have developed targets (e.g., goals of the Paris agreement) that seek to reduce their greenhouse gas emissions levels, particularly from the energy and transport sectors. The installation of large renewable generating capacities creates new challenges. Particularly, their high variability creates uncertainties to the energy system regulators and operators to guarantee the security of supply at affordable prices. Therefore, new approaches must be considered to help reduce the uncetainty associated with variable renewable energy. Power-to-X and demand response technologies, which provide a high degree of flexibility to energy systems, could be in fact a viable solution. This research compares two methods of planning the development of energy system. The developed software H2RES is being compared to the existing commercial energy system's configuration optimization program PLEXOS. The research compares these models in terms of endogenous capacity expansion of renewable sources and flexibility options Additionally, H2RES is extended to account for endogenous capacity investment decisions in power and energy storage technologies. The two models are compared on the case of the Croatian Energy system. Results show that Power-to-X technologies provide the required flexibility in order to successfully integrate new generating capacities of variable renewable sources, reaching economically optimal and low carbon energy systems. Newly developed software H2RES is shown to be capable in providing energy system simulations, optimization and investment planning. Displayed functionalities in some aspects have shown to be even more capable than in established software PLEXOS to which it is compared. There is as well high amount of room for improvements due to its open-source nature.