Georgios Gaidajis

Wintertime particulate mass concentrations in urban environment and the impact of economic crisis

The aim of the specific study is to discuss the impact of economic crisis on air quality in Greece in terms of particulate matter (PM) concentrations. For this purpose, three sampling campaigns were conducted during the winter period of 2012, 2013 and 2014 in two medium sized cities in North Greece (Kavala and Drama). The average concentrations measured ranged from 33–56, 28–47 and 25–44 μg/m3 for PM10, PM2.5 and PM1, respectively. The analysis of the daily concentration profile for all measurements indicated two distinct periods of elevated concentrations: a) during 08:00 to 10:00 and b) during 19:00 to 22:00. The observed periods of increased concentration coincided with the periods of increased urban traffic in the morning and basic heating needs in late evening. Significant correlation was observed between PM10-PM2.5 (R2>0.9) and PM2.5-PM1 (R2∼1.0) suggesting that coarse and fine particles originate from similar sources. The PM2.5/PM10 ratio values ranged from 0.84 to 0.85 indicating a major impact of PM2.5 to the final concentration levels recorded. The results presented in the specific study support the notion that a significant alteration is undergoing to the atmospheric air quality in Greece due to the economic crisis and the subsequent increase of biomass products combustion for residential heating. Supplemental materials are available for this article.

Environmental performance of renewable energy systems with the application of life-cycle assessment: a multi-Si photovoltaic module case study

Life-cycle thinking significantly affects the assessment of the environmental performance of a system. In this study, the life-cycle assessment of a multi-Si photovoltaic (PV) module was conducted in order to examine the environmental burden throughout its life cycle and benchmark it with the environmental burden of the identical conventional energy produced with the energy mix of Greece and supplied by the national energy network grid. The results indicated that aluminium, solar glass and the energy consumed during PV assembly significantly affected the environmental performance of the PV module. Non-renewable energy utilisation, global warming and respiratory inorganic emissions were the major impact categories affected by the life cycle of the module examined. Significant questions were raised regarding the distance of the PV installation site from manufacturers and maintenance personnel. Still, the utilisation of the system examined was more efficient than the application of conventional energy sources in terms of environmental performance.

Sustainability of Industrial Facilities through Water Indicators

One of the key parameters affecting the sustainability performance of industrial facilities is their ability to efficiently manage water resources and reduce water consumption. The aim of the specific study is to identify key indicators utilized for the evaluation of sustainable water consumption and management of industrial facilities that are included in sustainability assessment methods. For the specific purpose, a 3-step methodology was developed including a) the development of an indicator pool, b) the separation of indicators and c) evaluation and selection of key indicators. In total, twelve key indicators were identified. The specific indicators were further assessed based on five predefined criteria such as their efficiency in terms of time and cost required for their estimation, their ability to help decision making, their ability to cover long-term and wide spatial boundaries and others. A five-point grading system was applied to rank the indicators in order to help industries select the most appropriate ones according to their needs. Results indicated that there is still a significant potential of improvement in terms of how industries assess water related sustainability aspects. What seems to be the most important issue is the development of commonly accepted sustainability thresholds or goals per indicator, so that industries will be able to assess their distance from a truly sustainable performance. To serve this purpose, a normalization procedure including specific reference points for six key indicators is proposed.

Comparative evaluation of flat roof thermal systems in Greece

In the specific study, four flat roof thermal systems namely: the gravel ballasted roof, the green roof, the ventilated roof and the insulated false ceiling, were analysed with the application of the life cycle assessment method (LCA). The analysis of the systems was based on literature references, theoretical calculations and extensive simulation scenarios. Various parameters were evaluated such as cost and time of application, structural loads, maintenance needs and energy efficiency. The study focused on the comparative environmental evaluation of the systems. Results indicated that the ballasted roof exhibited the best environmental performance. Extruded polystyrene and steel parts were the key parameters affecting the environmental performance of the systems. Significant results are also provided regarding the energy reimbursement and technical characteristics. The conclusions of the specific study support the need to identify alternative materials and processes for the formation of the thermal roof ...

Sustainable development integration in Greek schools of engineering: current situation, experiences and actions

In this paper, a comprehensive study regarding the assessment of sustainable development (SD) integration in Greek schools of engineering is presented. More specifically, the undergraduate and graduate curricula and websites of all schools of engineering in Greece were examined to identify SD-related content and actions. Moreover, a simple guide for embedding SD into engineering schools was established, based on the experiences of successful implementation and strategies from highly recognised technical universities worldwide, to benchmark the Greek experience and to propose indicative measures for incorporating SD teaching in Greek universities. Results indicated that changing the curriculum is not the only way to efficiently incorporate SD in universities, whereas there are gaps concerning the integration of sustainability principles and tools in Greek engineering universities. Furthermore, the initial steps of incorporating SD-related actions at an engineering department are presented and analysed indicating some characteristic key factors affecting the efficient incorporation of SD tools in engineering courses.

Ambient air quality at the wider area of an industrial mining facility at Stratoni, Chalkidiki, Greece

To assess ambient air quality at the wider area of a mining-industrial facility in Chalkidiki, Greece, the particulate matter with an aerodynamic diameter of 10 μm (PM10) and its content in characteristic elements, i.e., As, Cd, Cu, Fe, Mn, Pb, Zn were monitored for a period of three years (2008–2010). Gravimetric air samplers were employed for the particulate matter sampling at three sampling stations located in the immediate vicinity of the industrial facility and at a neighbouring residential site. Monitoring data indicated that the 3-year median PM10 concentrations were 23.3 μg/m3 at the residential site close to the facility and 28.7 μg/m3 at the site within the facility indicating a minimal influence from the industrial activities to the air quality of the neighbouring residential area. Both annual average and median PM10 concentration levels were below the indicative European standards, whereas similar spatial and temporal variation was observed for the PM10 constituents. The average Pb concentrations measured for the three sampling sites were 0.2, 0.146 and 0.174 μg/m3 respectively, well below the indicative limit of 0.5 μg/m3. The quantitative and qualitative comparison of PM10 concentrations and its elemental constituent for the three sampling stations did not indicate any direct influence of the mining-industrial activities to the air quality of the Stratoni residential area.