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Abstract Under its Kyoto and EU obligations, Greece has committed to a greenhouse gas (GHG) emissions increase of at most 25% compared to 1990 levels, to be achieved during the period 2008–2012. Although this restriction was initially regarded as being realistic, information derived from GHG emissions inventories shows that an increase of approximately 28% has already taken place between 1990 and 2005, highlighting the need for immediate action. This paper explores the reallocation of production in Greece, on a sector-by-sector basis, in order to meet overall demand constraints and GHG emissions targets. We pose a constrained optimization problem, taking into account the Greek environmental input–output matrix for 2005, the amount of utilized energy and pollution reduction options. We examine two scenarios, limiting fluctuations in sectoral production to at most 10% and 15%, respectively, compared to baseline (2005) values. Our results indicate that (i) GHG emissions can be reduced significantly with relatively limited effects on GVP growth rates, and that (ii) greater cutbacks in GHG emissions can be achieved as more flexible production scenarios are allowed.

This paper presents a novel method for the forecasting of mean hourly wind speed data using time series analysis. The initial point for this approach is mainly the fact that none of the forecasting approaches for hourly data, that can be found in the literature, based on time series analysis or meteorological models, gives significantly lower prediction error than the elementary persistent approach. This was combined with the characteristics of the wind speed data, which are determined by the power spectrum values, distinguished by the spectral gap in intervals between 20 minutes and 2 hours. The finally proposed methodology is based on the multi-step forecasting of 10 minutes averaged data and the subsequent averaging to generate mean hourly predictions. When applied to two independent data sets, this approach outperformed by a factor of four, the conventional one which utilizes past mean hourly wind speed values as inputs to the forecasting models.

Abstract This work introduces an assessment of the projected climatic changes in wind characteristics in Greece through the WRF model 5 × 5 km2, forced by the EC-EARTH Global Climate Model (GCM). Firstly, the model is validated against historic observations at 10 m, before being applied to the Representative Concentration Pathways (RCPs) 4.5 and 8.5 that represent an average expected future and a worst-case scenario. Projected changes in the mean annual wind speed at 100 m, between the historic (1980–2004) and future (2020–2044) scenarios are found to vary locally between −5% and +20%, whereas for the Wind Energy Density (WED) this variation lies between −15% and +60%. Overall, robust and significant increases regarding the mean wind speeds were found mainly over the north and central-western Aegean region, the Island of Crete, as well over Greek mainland and the Ionian Sea. Both scenarios predicted higher statistically significant increases in the Weibull shape parameter values (of about 0.2) in the north–central Aegean, while the summer seasonal analysis, yielded significant decreases over the western Ionian Sea and south and south-western parts of Crete, which might be indicative of more gusty events. Finally, extreme wind speeds analysis indicated increases, which might affect wind turbines structural integrity.

Abstract The present work attempts to provide more accurate estimate of HDD and CDD and investigates the suitability of high resolution downscaled seasonal climatic forecasting models for assessing and accurately estimating the energy demands of buildings. The analysis has been established through a series of indices for estimating heating (HDD) and cooling degree days (CDD) using interpolated hourly data which were produced from the model output. The work has considerable potential to provide refined inputs for assessing building sector-specific vulnerability to climate change: energy supply and demand. In this work the application of the above mentioned methodological approach in the assessment of the energy performance and requirements of buildings on Greece are presented, for a period and with a forecast horizon of 6 months. The ARW-WRF model has been set up and validated to produce downscaled climatological fields for Greece, forced by the output of the CFSv2 model, with a horizontal spatial resolution of 5 km × 5 km. The data, that covered all Greek regions and climatology zones according to the existing building regulations code and the region elevation present a very reasonable correlation with data published in previous studies.