MA-DHC

MA-DHC is a research project that is developed within the framework of the Industrial Doctorate Plan of the Government of Catalonia in collaboration with the Polytechnic University of Catalonia for the period 2022-2024, within del Sustainability PhD program.

The research project consists of a PhD that is being carried out within the framework of the Plan for Industrial Doctorates of the Generalitat de Catalunya. On the one hand, new modelling and simulation techniques will be developed for the evaluation of 4GDHC and 5GDHC networks based on shallow geothermal resources complementary to other renewable energies oriented to the territory of Catalonia.

On the other hand, a new tool will be generated to help decision-making regarding its implementation within the scope of Catalonian urban sustainability. This tool will preferably be in the form of open access software for the design and sizing of modern district heating and cooling networks. It will be based on the integration of the geothermal data available and elaborated by the ICGC and will present a friendly enough graphical user interface in order to reach the widest possible audience.

 

Concept of 5th generation district heating and cooling network (ICGC, 2022; modified from Garcia-Céspedes, et al., 2022)

Framework of the MA-DHC project

Considering the final energy consumption of the EU, 40% corresponds to the building sector, which represents 36% of greenhouse gas emissions. From a different perspective, 50% of energy end uses are for heating and cooling, where the building sector represents the 80%.

In order to achieve climate neutrality in 2050 in the EU territory, in accordance with its long-term strategy, it is necessary to promote in this sector an increase in its energy efficiency and a massive use of renewable energies, and in particular, of thermal renewable energy.

Besides, the effects of climate change are also leading to a progressive increase in cooling needs in the building stock, especially in Mediterranean countries and temperate climates.

Up to 50% of the demand for cold and heat in the EU could be generated under the scheme of district heating, cooling and domestic hot water (DHW) networks by 2050. For this reason, one of the key technologies that Europe is promoting to achieve its decarbonisation goals and to fight against climate change are smart, flexible and optimized low and very low temperature district networks, also known as 4th and 5th generation district heating and cooling networks (4GDHC and 5GDHC networks, respectively). These networks will operate exclusively with local and 100% renewable sources, especially with efficient technologies such as the ground source heat pump (GSHP). Precisely, in densely populated areas, the 4GDHC and 5GDHC networks represent the best scenario for taking advantage of such a clean, efficient, available and local renewable thermal resource as shallow geothermal energy. This includes open-loop systems (use of thermal energy present in both surface and underground water masses) and closed-loop systems (use of thermal energy present in the subsoil), as well as underground thermal storage systems. In addition, modern district networks allow the combination of various renewable technologies at the same time, creating obvious synergies such as the hybridization of shallow geothermal energy with photovoltaic solar energy.

In order to assess the use of shallow geothermal resources and their application in efficient heating and cooling networks, it is necessary to create tools for a rapid modelling process. This should be used by technicians in the early phases of studies and projects, aiding further decision making involving the integration of 4GDHC or 5GDHC networks schemes in urban areas. Moreover, a strong didactic component is necessary in this type of tool to help raise society's awareness of the existence of shallow geothermal resources and their benefits.