Community energy systems as decentralized and collective renewable energy systems, where the energy is jointly generated and distributed among a community of households, are gaining momentum. The collective action of individual households as a core characteristic of such energy systems influences the energy availability, energy costs, and eventually, their energy security. This study investigates the influence of individual households' behavioural attributes on the energy security of such collective energy systems. An agent-based model was built based on the following energy security dimensions: availability, affordability, accessibility and acceptability, referred to as the 4A's concept. The research focused on thermal energy communities given the considerable share of thermal energy applications, such as heating, cooling, and hot tap water. The simulation results demonstrated that such communities could cost around 1250 €/year while reducing their CO2 emissions by 50% on average. Environmentally friendly behaviour leads to higher energy security performances. Such behaviours considerably influence the technical configurations while contributing positively to affordability and acceptability dimensions of collective energy security of thermal energy systems. Furthermore, the investment size of individual households was found to be the most influential parameter for energy security performances, while natural gas prices were identified as the least impactful parameter.

In community energy systems, the energy demand of a group of households is met by collectively generated electricity and heat from renewable energy sources. What makes these systems unique is their collective and collaborative form of organization and their distributed energy generation. While these features are crucial to the resilience of these systems and are beneficial for the sustainable energy transition in general, they may at the same time undermine the security of energy within these systems. This paper takes a comprehensive view of the energy security of community energy systems by considering dimensions such as energy price, environment and availability, which are all impacted by decentralized and collective means of energy generation and distribution. The study analyses community energy systems' technical and institutional characteristics that influence their energy security. An agent-based modelling approach is used for the first time to study energy security, focusing on thermal energy communities given the considerable share of thermal energy applications such as heating, cooling, and hot tap water. The simulation results articulate that energy communities are capable of contributing to the energy security of individual households. Results demonstrated the substantial potential of energy communities in CO2 emissions reduction (60% on average) while being affordable in the long run. In addition, the results show the importance of project leadership (particularly regarding the municipality) concerning energy security performances. Finally, the results reveal that the amount of available subsidy and natural gas prices are relatively more effective for ensuring high energy security levels than CO2 taxes.

This thesis aims to support the design and implementation of energy-secure thermal energy communities (TEC) by investigating their technical, behavioural and institutional settings through a collective action perspective. The thesis shows that energy-secure TEC initiatives are collective energy systems with particular characteristics and surrounding conditions. The thesis demonstrates, by building and using a number of agent-based models, that behavioural and institutional settings are relatively more influential than technical settings for establishing and sustaining the functioning of energy-secure collective thermal energy systems. In particular, a combination of aquifer thermal energy storage with heat pumps positively impacted TEC initiatives' energy security. The most crucial technical requirement for the energy security of TEC initiatives is a connection to a natural gas grid. The thesis recommends that individual households initiate their own (thermal) energy communities, and policy-makers support such initiatives.

Energy communities are decentralized socio-technical systems where energy is jointly generated and distributed among a community of households locally. As the energy that is shared among the community is commonly electricity, the energy community's literature is dominated by electricity-systems and mostly neglects collective thermal energy as an alternative energy carrier for heating and cooling. Our goal in this article is to organise the existing research on “community-based initiatives for heating and cooling ” by using the Institutional Analysis and Development (IAD) framework, and based on this analysis, identify a future research agenda. Our analysis reveals that the number of publications in this area has been growing fast recently, focusing on technological challenges. Fewer papers take an institutional point of view, in which they cover policies, price reforms and values. The institutionally oriented papers focus on solar thermal energy and bio-based thermal energy. Other thermal technologies, such as geothermal wells, are largely neglected in the literature, but are known to have different institutional constraints. Informal rules and values are mainly researched from a consumer perspective. Since energy communities often consist of consumers and prosumers, additional research is warranted into this area. Evaluative criteria for such communities are limited to economic aspects and greenhouse gas emissions, while indicators such as soil pollution and spatial planning that may play an equally important role are neglected. We recommend studying thermal energy communities as distinctive entities with their own unique characteristics, and we develop a research agenda for this purpose.

Energy communities are gaining momentum in the context of the energy transition. Given the distributed and collective action nature of energy communities, energy security of these local energy systems is more than just security of supply and related to issues such as affordability and acceptability of energy to members of the community. We build an agent-based model of energy communities to explore their security challenges. The security dimensions we consider are availability, affordability, accessibility and acceptability, which are referred to as the 4As. The results confirmed that there is always a trade-off between all four dimensions and that although it is difficult to achieve a high energy security performance, it is feasible. Results also showed that among factors influencing energy security, the investment of the community plays the biggest role.

Energy communities are key elements for local energy transitions, collectively generating, distributing and consuming energy, using renewable energy technologies. Thermal energy communities, as one type of energy community, are focused on thermal energy applications, such as heating, cooling, bathing, showering and providing hot tap water. As thermal energy applications and systems receive increasing academic and policy attention, there is a need to better understand the formation processes they undergo. In this study, various technical and institutional conditions are explored that influence thermal energy community formation processes by using an agent-based modelling approach. The results show that technology selection is not the most crucial and determining factor for the success of thermal energy communities, yet the surrounding institutional conditions are. Key factors that influence these formation processes pertain to providing training, so that the thermal energy community leaders become more skilled, and allocating subsidies based on the projects’ degree of environmental friendliness. For all stakeholders, finding the balance between all of the decision-making criteria is key to success. The results are useful for practitioners - and especially for policy makers - to develop more impactful policies and strategies to support the expansion of local thermal energy communities.

Energy communities are key elements in the energy transition at the local level as they aim to generate and distribute energy based on renewable energy technologies locally. The literature on community energy systems is dominated by the study of electricity systems. Yet, thermal energy applications cover 75% of the total energy consumption in households and small businesses. Community-driven initiatives for local generation and distribution of thermal energy, however, remain largely unaddressed in the literature. Since thermal energy communities are relatively new in the energy transition discussions, it is important to have a better understanding of thermal energy community systems and how these systems function. The starting point of this understanding is to study factors that influence the formation and continuation of thermal energy communities. To work towards this aim, an abstract agent-based model has been developed that explores four seemingly trivial factors, namely: neighborhood size, minimum member requirement, satisfaction factor and drop-out factor. Our preliminary modelling results indicate correlations between thermal community formation and the 'formation capability' (the percentage of households that joined) and with the satisfaction of households. No relation was found with the size of the community (in terms of number of households) or with the 'drop-out factor' (individual households that quit after the contract time).