Introduction

ROBINSON project intends to create and evaluate an integrated energy system targeted at industrialized islands, exploiting locally accessible energy sources, electrical and thermal networks, and contemporary storage technologies. Also, it aspires to decrease energy losses, enhance the stability and dependability of the energy system, minimize the environmental consequences, and lead to fossil-fuel savings. A macro-objective of the project is to play a fundamental role in supporting the islands' energy transition by creating a replicable solution.

One of the obstacles that hinder European islands from reducing their reliance on fossil fuels and fully using the potential of their local renewable resources, such as wind and sunlight, is the unpredictability and lack of flexibility of their energy systems. The systematic and precise assessment of renewable energy potential is crucial for the effective design of any renewable energy infrastructure (Gong et al., 2021). Due to the high dependability on RES, the accurate and reliable estimation of the local RES potential is critical for all the stages of this project.

Meteorological data are the easiest to acquire, enabling the selection of the most proper and reliable RES for each specific region/area. The relevant datasets include time series for significant parameters such as temperature, wind speed, sun hours, and others. For example, the typical seasonal profiles of solar radiation and ambient temperature for Eagerly, are demonstrated in Figure 2 and Figure 3.

The estimation of the local RES potential is of utmost importance for the project due to its direct connection to the renewable hydrogen production system, as well as the exploitation of the biomass resources in each case, enhancing the factor of satisfying the pillars of the circular economy.

As it has been already mentioned, Eigerøy will be the demo island, while Crete and Stornoway will be the follower islands. Their indicative potential for the two most common RE technologies is depicted in Figure 8: The left subplot shows the monthly PV electricity generation (per kWp solar panel with a tilt of 35° and the solar azimuth of 180°) on Crete (blue), Eigerøy (orange) and Western Isles (green) in the year 2019-2020. The right subplot shows the monthly wind electricity generation (per kWp, for a Vestas V90 2000) on Crete (blue), Eigerøy (orange), and Western isles (green) in years 2019-2020.Figure 8.

Figure 4 The left subplot shows the monthly PV electricity generation (per kWp solar panel with a tilt of 35° and the solar azimuth of 180°) on Crete (blue), Eigerøy (orange), and Western Isles (green) in the year 2019-2020. The right subplot shows the monthly wind electricity generation (per kWp, for a Vestas V90 2000) on Crete (blue), Eigerøy (orange), and Western isles (green) in years 2019-2020.

There are several tools for evaluating the RES potential in any desired location, such as PVGIS, IRENA Global Atlas, Pan European Thermal Atlas, NASA POWER Database, Meteonorm, etc.), as described in RES Potential Estimation section.