Spectroradiometry in PV: how inter-laboratory comparison may improve measurement accuracy

Spectroradiometry is a key metrological discipline for accurate testing of photovoltaic (PV) devices, particularly relevant both for indoor testing on solar simulators and for outdoor testing, where differences between the available thermal energy and the energy usable by PV modules are relevant. In fact, as to indoor testing, the uncertainty in the spectral mismatch between the testing light source and the reference spectral irradiance may give rise to deviations up to 1-3% when measuring the maximum power even on a Class A solar simulator. Experimental uncertainty is expected to increase even further after the publication of the new revision of IEC 60904-9 (“Solar simulator performance requirements”), which is due by 2018. As to outdoor testing, accurate knowledge of solar spectral irradiance is important also for energy rating purposes, in view of the publication of IEC 61853 part 3 (“Energy rating of PV modules”) and part 4 (“Standard reference climatic profiles”). The relevance of accurate measurements of solar spectral irradiance has led the most renowned accredited European solar PV test centres to take part to a series of International Spetroradiometer Intercomparisons that has taken place every year so far since 2011 in various localities in the Mediterranean Basin. The ever-growing number of participating laboratories is both a consequence and a key of success of the whole exercise: ISO 17025 accredited laboratories are willing to receive confirmation of the stability and accuracy of their spectroradiometers and that can be done only when a conspicuous number of testing centres is involved. This paper summarizes the outcomes of the last intercomparisons, trying to highlight whether improvements in measurement reproducibility can be inferred from those partners that have participated since the earliest editions. The work gives new insights into spectroradiometry for both outdoor and indoor testing applications.JRC.C.2-Energy Efficiency and Renewable

Impacts of use and abuse of nature in catalonia with proposals for sustainable management.

This paper provides an overview of the last 40 years of use, and in many cases abuse, of the natural resources in Catalonia, a country that is representative of European countries in general, and especially those in the Mediterranean region. It analyses the use of natural resources made by mining, agriculture, livestock, logging, fishing, nature tourism, and energy production and consumption. This use results in an ecological footprint, i.e., the productive land and sea surface required to generate the consumed resources and absorb the resulting waste, which is about seven times the amount available, a very high number but very similar to other European countries. This overexploitation of natural resources has a huge impact on land and its different forms of cover, air, and water. For the last 25 years, forests and urban areas have each gained almost 3% more of the territory at the expense of agricultural land; those municipalities bordering the sea have increased their number of inhabitants and activity, and although they only occupy 6.7% of the total surface area, they account for 43.3% of the population; air quality has stabilized since the turn of the century, and there has been some improvement in the state of aquatic ecosystems, but still only 36% are in good condition, while the remainder have suffered morphological changes and different forms of nonpoint source pollution; meanwhile the biodiversity of flora and fauna remains still under threat. Environmental policies do not go far enough so there is a need for revision of the legislation related to environmental impact and the protection of natural areas, flora, and fauna. The promotion of environmental research must be accompanied by environmental education to foster a society which ismore knowledgeable, has more control and influence over the decisions that deeply affect it. Indeed, nature conservation goes hand in hand with other social and economic challenges that require a more sustainable vision. Today’s problems with nature derive from the current economic model, which is environmentally unsustainable in that it does not take into account environmental impacts. Lastly, we propose a series of reasonable and feasible priority measures and actions related to each use made of the country’s natural resources, to the impacts they have had, and to their management, in the hope that these can contribute to improving the conservation and management of the environment and biodiversity and move towards sustainability