Report Open Access

Social issues of novel renewable energy heating/cooling systems D2.1

Friedrich, Thomas; Stieß, Immanuel

This Deliverable 2.1 presents the results of Task 2.1 “Social issues enabling acceptance” and Task 2.2 "Safety, regulatory and market barriers" of the TRI-HP project, which aims to develop systems based on electrically driven natural refrigerant heat pumps coupled with PV to provide heating, cooling and electricity to multi-family buildings with an on-site renewable share of 80% reducing the installation cost by 10–15%. The objective of working package 2 (WP 2) is to understand potential social impacts of TRI-HP systems and improve the stakeholders’ acceptance towards these systems. Particular emphasis is given to market acceptance in order to understand potential barriers and hindrances for the adoption of TRI-HP by market participants. Furthermore, the institutional settings of Renewable energies (RE) by key stakeholders (socio-political acceptance) and the views of local stakeholders and residents (community acceptance) are considered.

Based on a literature review focusing on empirical social science studies on the acceptance and adoption of innovative renewable heating and cooling systems (RE H/C), key social and contextual factors are identified in this report that could promote or impede further developing and upscaling of TRI-HP systems. Empirical surveys show a general agreement on RE in Europe from which TRI-HP can take advantage. RE H/C and electricity systems are well accepted. However, this ‘acceptance in principle’ does not necessarily lead to an active adoption of TRI-HP systems. For example, despite the generally high level of social acceptance and widespread awareness of REs in Europe, public comprehension of RE H/C technologies is still low. Furthermore, specific local context conditions, such as the structure of the buildings stock, the tradition of housing tenure as well as national and local governance may provide additional barriers that need to be considered carefully.

In order to determine these factors more accurately, the perception and social acceptance of individual RE H/C technologies and components, i.e. heat pump (HP), solar thermal (ST), photovoltaics (PV), use of natural refrigerants and smart control are analysed and discussed. The findings show that economic and non-economic factors, like socio-cultural issues, local contexts and user practices play an important role for the acceptance of RE H/C systems and must be seriously taken into account for TRI-HP systems. The compilation of empirical examples suggests that the respective individual technologies that are part of the TRI-HP systems have their own issues and that these issues can vary from stakeholder to stakeholder.

Main barriers for TRI-HP to overcome are a lack of awareness towards HPs in many European countries, high installation costs, in particular in existing buildings, long payback periods, the structure of the building stock and legal restrictions due to the conservation of historical buildings and building ensembles which can restrict the use of PV and ST. Other barriers are different decision-making processes in condominiums and a high complexity of hybrid systems, while many users are reluctant to adapt heating habits to a new technology.

A switch towards RE H/C systems can be supported by non-monetary benefits of HPs, such as thermal comfort, safety etc., but needs also supportive political and market framework conditions (e.g. the availability of reliable funding and financial services). On a personal level, environmental concerns of potential adopters are conductive factors that support the adoption of RE H/C.
Thermal storage is an essential feature of TRI-HP systems. Studies on battery storage suggest that flexibility and enhanced self-supply are appealing to homeowners and could support the adoption of TRI-HP. However, additional costs for storage could also increase upfront costs and boost existing barriers against the use of ST and PV. Furthermore, householders’ capacity for load shifting is limited by the inertia of routinized practices of energy use. These restrictions have to be taken into account when assessing the overall performance of TRI-HP systems.

The acceptance of natural refrigerants, such as CO2 and propane, is mainly depending on a safe and reliable installation and operation of TRI-HP systems. Main barriers TRI-HP needs to address are safety hazards and capacity building and education of installers, maintenance technicians and consumers etc. A detailed analysis of regulatory barriers is presented in chapter 4. Insights from social studies of science and technology underline the need to include professionals as important stakeholders from the beginning. TRI-HP should not only focus on investors and planners as decision-makers, but should also take ‘middle actors’ such as HVAC consultants, technicians, operators and intermediary actors (energy agencies etc.) into account.

A gender analysis shows that RE H/C systems are not ‘gender-neutral’ and gender has an influence on the perception, adoption and use of RE H/C systems. Gender aspects are highly relevant for the TRI-HP project and should be considered in order to enhance the acceptance of RE H/C technologies. A higher environmental concern of women has been identified as an important factor that supports energy transitions and can promote the acceptance of RE, both in personal and professional contexts. Women tend to have a higher carbon print at home since they are still the primary home carer. However, women are still underrepresented in the energy sector and H/C areas. H/C technologies intersect with gendered practices in private households. However, up to now the empirical thermal comfort model that is based on a metabolic rate of an average man, is failing to match the needs of women. Respecting these links can help to question implicit assumptions in technology development in order to get a more realistic picture of the users’ needs. In particular, the different biophysical requirements of women and men related to the experience of thermal comfort have to be taken into account. The specific needs of women to control H/C of indoor environments provide another issue that should be considered when designing the user-system interface.

The reviews on standards, regulations and on market barriers points to further issues that are to be respected. Important topics are maximum refrigerant charges, requirements for components as a function of design pressure, temperature limitations with hydrocarbons, construction requirements, testing, etc. Furthermore, energy efficiency and labelling requirements are discussed. Particular emphasis is given to hydrocarbons and CO2 as working fluids in TRI-HP HPs. Market barriers for propane HPs emerge from safety concerns regarding the high flammability of propane, additional manufacturing costs due to the characteristics of propane and lack of knowledge and training needed for developers, installers and maintainers and limitations on refrigerant charge. Main market barriers for CO2 HPs are costs, which are linked to the low critical temperature and a lack of training and knowledge about CO2 vapour compression systems.

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