The increase in global electricity demand, along with its impact on climate change, call for integrating sustainability aspects in the power system expansion planning. Sustainable power generation planning needs to fulfill different, often contradictory, objectives. This paper proposes a multi-objective optimisation model integrating four objective functions, including minimisation of total discounted costs, carbon emissions, land use, and social opposition. Other factors addressed in the model include renewable energy share, jobs created, mortality rates, and energy diversity, among others. Single-objective linear optimisations are initially performed to investigate the impact of each objective function on the resulting power generation mix. Minimising land use and discounted total costs favoured fossil fuels technologies, as opposed to minimising carbon emissions, which resulted in increased renewable energy shares. Minimising social opposition also favoured renewable energy shares, except for hydropower and onshore wind technologies. Accordingly, to investigate the trade-offs among the objective functions, Pareto front candidates for each pair of objective functions were generated, indicating a strong correlation between the minimisation of carbon emissions and the social opposition. Limited trade-offs were also observed between the minimisation of costs and land use. Integrating the objective functions in the multi-objective model resulted in various non-dominated solutions. This tool aims to enable decision-makers identify the trade-offs when optimising the power system under different objectives and determine the most suitable electricity generation mix.

With many offshore wind turbines (OWTs) approaching the end of their estimated service life, there is an increasing demand for developing and evaluating end-of-life strategies that can maximize these assets’ value while at the same time satisfying the requirements of the stakeholders involved. This study aims to perform a detailed review and develop a framework that will consider multiple criteria in the decision-making process, presenting and discussing available technologies and strategies, as well as influencing factors such as schedule, cost and environmental impact. Service life extension, repowering and decommissioning are included in this review as the main end-of-life strategies considered by asset owners, and these are translated into four processes that are applicable to offshore wind farms through a generic decision tree. A SWOT analysis is also conducted which aims to compare the different characteristics of the proposed processes. The factors contributing to the uncertainty of the processes as well as lessons learnt from the oil & gas industry are also discussed.

In the efforts to decarbonise the heat sector, heat pumps can offer a cost-effective transition away from fossil fuels. Water Source Heat Pumps (WSHP) can be utilised in cases where ambient water sources (river, ground water, abandoned mines water) are present. However, the economic benefits of different levels of heat pump centralisation as well as their comparative advantages over other decentralised options such as individual Air Source Heat Pumps (ASHP) or Gas Boilers (GB) remain uncertain and further investigations are necessary to fully assess their potential. This study introduces CATHeaPS, a Centralisation Analysis Tool for Heat Pump Systems, a user-friendly open access modelling tool that enables the technoeconomic assessment of (a) district heating networks with a centralised WSHP, and (b) ambient networks with decentralised building level WSHPs against individual ASHPs and GB for a range of consumer classes. CATHeaPS provides a complete project cashflow for each supply option and is verified against published data and outputs from a UK industrial case study, with slightly altered data to ensure confidentiality. A data analysis highlights the break-even points for the number of residential properties, beyond which centralised solutions are more economic than decentralised energy supply options for different housing densities. A thorough sensitivity analysis is also conducted to identify the impact of different input parameters on the levelised cost of energy of each supply option. It is found that discount rate has the largest impact for both networks, followed by CAPEX and energy costs. This study aims to help stakeholders and decision makers in two ways. It introduces a novel, easy-to-use open access technoeconomic tool that enables a high-level analysis of energy, hydraulic and economic factors for any project area. Furthermore, it maps the boundaries of beneficial operation for different levels of centralisation for residential consumers and gives preliminary suggestions on which energy supply option is better suited to a given project.

One of the major challenges regarding energy transition is to create active support towards renewable energy installations on a local level. The CROWDTHERMAL project presents practical approaches for involving local stakeholders in different measures in order to develop acceptable solutions. Based on technical evidence and data from concrete case studies, the project shows ways how community funding can increase social acceptance towards geothermal energy installations. The presented solutions are based on alternative financial schemes studies and risk mitigation analysis in geothermal projects.

This paper presents a decision support tool for promoters/investors of geothermal energy projects, based on a decision tree (DT) structure. The DT aims to assist stakeholders to select public engagement strategies, alternative financing solutions and risk mitigation measures (or options) for geothermal energy projects. Public engagement is necessary for the successful development and operation of geothermal projects. Available studies (including toolkits and protocols) commonly list a set of practices for social engagement without providing information on the factors which render certain options more suitable than others. The presented tool offers a transparent framework to how relevant decisions could be managed by providing a sequence of questions that focus on social, environmental, resource risk, and financial influencing factors and to realise community engagement into geothermal projects. This work is part of the Horizon 2020 CROWDTHERMAL project, which aims at empowering the public to directly participate in the development of geothermal projects through social engagement tools and alternative financing schemes, like crowdfunding.