Transformations of the energy system in the context of the decarbonisation of the EU economy in the time horizon to 2050

This paper presents the main energy-related projections for various scenarios quantified with the PRIMES energy system model, used for the impact assessment study accompanying “Roadmap for moving to a competitive low-carbon economy in 2050” published in March 2011 by the European Commission.The analysis shows that decarbonising the EU economy in the time horizon to 2050 is feasible with currently known technologies provided that considerable restructuring in energy demand and supply sectors goes together with technology improvement. Energy system costs will have to increase, with capital costs increasing significantly. The results confirm that strategies combining all decarbonisation options are more cost-efficient than strategies excluding some options. Keywords: Energy policy, Climate policy, Energy analysis, Energy modellin

Model-based analysis of decarbonising the EU economy in the time horizon to 2050

This paper describes the methodology of using the PRIMES energy system model to quantify various scenarios accompanying the “Roadmap for moving to a competitive low-carbon economy in 2050” published in March 2011 by the European Commission. The paper focuses as well on emission and cost implications.The model based analysis finds that the decarbonisation of the energy system is possible with technologies known today; the power generation sector reduces emissions the most, but also demand side sectors reduce their emissions considerably. Despite considerable restructuring towards using electricity, transportation shows residual emissions by 2050 mainly due to the long-distance road freight transport and aviation. The energy system costs for decarbonisation were found to represent between 0.24 and 1.63 percentage points of cumulative GDP over the time period 2010–2050 higher than in a Reference scenario case which obtains the Climate and Energy package targets in 2020 and a long-term target of 40% emission reductions compared to 1990. The cost range depends on the timely availability of certain decarbonisation options (e.g. CCS, electrification in transportation) and on the extent of emission reduction actions worldwide. Keywords: Energy policy, Climate policy, Energy analysis, Energy modellin

Interactions between salinity and irrigation frequency in greenhouse pepper grown in closed-cycle hydroponic systems

Two different irrigation regimes with two different salinity levels were applied to peppers (Capsicum annum L.) grown in closed hydroponic systems in a glasshouse. The two salinity levels were attained by adding NaCl to the irrigation water used to prepare nutrient solution to obtain concentrations of 0.8 and 6 mol m(-3), and allowing the salts to progressively accumulate in the recycled nutrient solution. The two salinity levels were combined with two different levels of irrigation frequency in a two-factorial experimental design. Initially, the Na and Cl concentrations increased rapidly in the recycled effluents, but nearly three months after treatment initiation they converged gradually to maximal levels depending on the NaCl treatment. The low irrigation frequency imposed a more rapid salt accumulation in the root zone, which was ascribed to restriction of the volume of drainage solution. However, the maximal salt concentrations in the root zone were independent of the watering schedule. This finding agrees with previous research revealing that the maximal salt accumulation in the root zone of plants, grown in closed hydroponics, is dictated merely by the NaCl concentration in the irrigation water. Total and Class I yields were suppressed by salt accumulation but the high irrigation frequency significantly mitigated the deleterious salinity effects. At low salinity, the low irrigation frequency raised significantly the weight percentage of fruits with blossom-end rot (BER), whereas at high salinity the incidence of BER was further increased without significant differences due to the irrigation regime. Frequent irrigation resulting in high drainage fractions in closed hydroponic systems may delay the rate of salt accumulation in the root zone, thereby enhancing yield and improving fruit quality, without increasing the discharge of polluting fertigation effluents to the environment

Evaluation of water footprint for table olive groves of Olea europaea L. 'Konservolea'

As agriculture appears to be globally the greatest water user and water scarcity, due to fresh water shortages or deterioration of fresh water quality, is listed among the major global risks, efficient use of water resources is closely linked to sustainable agricultural practices. Water footprint (WF) has been largely employed during the last decade as a useful tool for planning efficient water management strategies at global, national, regional or even water basin level. WF is an indicator that is based on methods and tools that calculate the amount of water used along the full supply chain of a product. 'Konservolea' is a local table olive cultivar assigned as a protected geographical indication (PGI) product of Arta, Greece. It is the main table olive cultivar in the area, it has a significant impact on local economy and it exhibits favorable economic and market prospects. In this study the WF of 'Konservolea' was calculated based on actual data from four olive groves and the results are presented and discussed. All four groves were conventionally treated according to the local practices regarding pruning, fertilisation, plant protection, etc. Three of the olive groves were irrigated, while the fourth was rainfed. The WF of the four olive groves ranged from 354 to 961 m3 t-1 of olive fruit. The results provide a first yet solid assessment of the WF of table olive crop in the area and underline the effect of different agronomic practices on WF. Practical difficulties regarding the calculation of WF that need to be further investigated and resolved are pointed out. © 2022 International Society for Horticultural Science. All rights reserved

Power generation technology clusters: present status and its potential

This chapter presents a general discussion on the present state and likely future developments in a number of groups of related power generation technologies. These groups, or clusters, of technologies then form the basis of the technology scenarios presented and analysed in later chapters