No abstract

Global and diffuse horizontal illuminance data are analysed for Athens, Greece, for the period 1992-1997. It is shown in a graphical manner that horizontal illuminance (global and diffuse) is dependent upon the time of the day and the month of the year. The diagrams are categorized according to Perraudeau's nebulosity index, which re ects the sky cover and the climate at a given area. The cumulative frequency distribution of the parameters under all-sky types are estimated and discussed. Some examples of sky-luminance distributions using appropriate software are given. The conclusions are of potential value to local architectural practice, installations of lighting, and in developing an energy-saving policy for the Athens region.

Geothermal project development entails a number of risks, the most significant of which is the geological risk. The introduction of a risk mitigation scheme (RMS) might enable project developers to shift some of the geological risk to public or private entities. Keeping the above in mind, the objective of this study is to examine the development of an effective and financially feasible geothermal risk mitigation scheme in Greece, i.e., a country with no such scheme available. In this respect, the existing status of the geothermal sector in the country is presented, followed by an evaluation of the financial sustainability of a potential RMS, taking into account different insurance premiums, risk coverages, and project success rates. The results indicate that alternative insurance premium, risk coverage, and success rate requirements would result in different financial preconditions for the foundation either of a public or a private fund. Keeping in mind that in most examined scenarios the initial RMS capital is expended before the end of the ending of the scheme, it is suggested that such a plan can only be initiated by the public sector, which is typical of countries with little-developed geothermal markets.

Linear climate mitigation models look into aggregated economic sectors and model greenhouse gas (GHG) emissions disregarding downstream value chains, making particular sectors accountable for downstream (or upstream) GHG emissions. Hence, the present climate mitigation models inconsistently account for indirect GHG emissions; underrepresent upstream and downstream value chains; do not address Circular Economy (CE) practices; do not cover resource consumption, thus not considering materials’ circularity. To provide curated policy support for decision-making for carbon neutrality and other Sustainable Development Goals (SDGs), models need to shift from linear to circular. To achieve this, a link between energy-climate mitigation modelling and cradle-to-cradle assessment CE analytical tools must be established. This is the core issue covered in the CO2NSTRUCT Horizon project (2022-2026). CO2NSTRUCT proposes a framework to supplement the well-established JRC-EU-TIMES model, using a highly comprehensive technological representation with CE measures. The framework will apply CE measures to the value chain of six carbon-intensive construction materials (i.e., cement, steel, brick, glass, wood, and insulation materials) and will provide new components to the JRC-EU-TIMES model, including citizen behaviour; societal impacts; rebound effects; supply and value chains. The results will be used for policy approaches integrating CE into climate change mitigation actions.