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During the Engineering Validation and Engineering Design Activities (EVEDA) phase (2007-2014) of the International Fusion Materials Irradiation Facility (IFMIF), an advanced engineering design of the High Flux Test Module (HFTM) has been developed with the objective to facilitate the controlled irradiation of steel samples in the high flux area directly behind the IFMIF neutron source. The development process addressed included manufacturing techniques, CAD, neutronic, thermal-hydraulic and mechanical anal- yses complemented by a series of validation activities. Validation included manufacturing of 1:1 parts and mockups, test of prototypes in the FLEX and HELOKA-LP helium loops of KIT for verification of the thermal and mechanical properties, and irradiation of specimen filled capsule prototypes in the BR2 test reactor. The prototyping activities were backed by several R&D studies addressing focused issues like han- dling of liquid NaK (as filling medium) and insertion of Small Specimen Test Technique (SSTT) specimens into the irradiation capsules. This paper provides an up-todate design description of the HFTM irradiation device, and reports on the achieved performance criteria related to the requirements. Results of the vali- dation activities are accounted for and the most important issues for further development are identified.

This study proposes a coordinated and distributed smart grid based method for optimal set points of distributed generators (DGs) as well as on‐load tap changer (OLTC) transformer in the unbalanced power distribution grid. In this approach, energy efficiency is improved and voltage profile is kept in an acceptable range under different operating conditions of renewable energy resources and loads. In the first level of proposed hierarchical method, DGs are independently trying to keep voltage profile in an acceptable range in an optimal way. If the first level is not succeeding, at the second level, OLTC cooperates with the first level to eliminate the voltage violation in the system. The rules for updating control setting are derived based on distributed gradient algorithm. The proposed distributed solution presents analogous steady state results in comparison with centralised optimisation solution. Since the processing data is reduced, short‐timed response to change operating conditions could be achieved. Simulation results on three distribution test systems with different sizes demonstrate the effectiveness of proposed control solution.

This paper presents a stochastic factor based approach to mid-term modeling of spot prices in deregulated electricity markets. The fundamentals affecting the spot price are modeled independently and a market equilibrium model combines them to form spot price. Main advantage of the model is the transparency of the generated prices because each underlying factor and the dynamics between factors can be modeled and studied in detail. Paper shows realistic numerical examples on the forerunner Scandinavian electricity market. The model is used to price an exotic electricity derivative.

Abstract Algae have been considered as a promising biodiesel feedstock. One of the major factors affecting large-scale algae technology application is poor wintering cultivation performance. In this study, an integrated approach is investigated combining freshwater microalgae Chlorella zofingiensis wintering cultivation in pilot-scale photobioreactors with artificial wastewater treatment. Mixotrophic culture with the addition of acetic acid (pH-regulation group) and autotrophic culture (control group) were designed, and the characteristics of algal growth, lipid and biodiesel production, and nitrogen and phosphate removal were examined. The results showed that, by using acetic acid three times per day to regulate pH at between 6.8 and 7.2, the total nitrogen (TN) and total phosphate (TP) removal could be increased from 45.2% to 73.5% and from 92.2% to 100%, respectively. Higher biomass productivity of 66.94 mg L−1 day−1 with specific growth rate of 0.260 day−1 was achieved in the pH-regulation group. The lipid content was much higher when using acetic acid to regulate pH, and the relative lipid productivity reached 37.48 mg L−1 day−1. The biodiesel yield in the pH-regulated group was 19.44% of dry weight, with 16–18 carbons as the most abundant composition for fatty acid methyl esters. The findings of the study prove that pH adjustment using acetic acid is efficient in cultivating C. zofingiensis in wastewater in winter for biodiesel production and nutrient reduction.

Power flow partitioning is a topic of interest for European transmission system operators because of the increasing amount of Unscheduled Flows, which can cause congestions. Unscheduled Flows are caused by the transition to more and more renewable energy sources and the rising complexity of the European transnational energy market with insufficient price signals. To identify different flow types, the Full Line Decomposition (FLD) method can be used. The trend of grid extension goes more towards flexible AC transmission systems (FACTS) which have to be considered in a special way, since the actively changed power flow cannot be identified by FLD. New methods have to be developed. This publication presents a way to calculate and to classify partial power flows caused by FACTS, especially by high voltage DC (HVDC) transmission systems using the proportional sharing principle.

Abstract Important aspects of electricity system planning are overall yearly electricity consumption and information about variations in consumption. These variations will influence the capacity that has to be installed, as well as the type and quantity of fuel that will be used. Using only economic, socio-economic, technical and meteorological indicators, we have developed a model that can predict the hourly load shape. This model is based on a division of the total electricity-consumption into 60 economic sectors and electrical appliances. For each of these sectors, a load shape is formed. Summation over sectors then gives the total hourly electricity consumption pattern. To test this model, the hour-to-hour load shape of the Dutch public grid for 1980 was formulated and compared with the actual load shape. The root-mean-square difference between the estimated and actual load shapes is 5% of the mean hourly load. The accuracy of the estimated maximum load for every week is of the same magnitude as that used for electricity-supply system planning over the short term. We conclude that our model can be used for long-term load shape forecasting.

Heating and cooling using aquifer thermal energy storage (ATES) has hardly been applied outside the Netherlands, even though it could make a valuable contribution to the energy transition. The Climate-KIC project "Europe-wide Use of Energy from aquifers" - E-USE(aq) - aimed to pave the way for Europe-wide application of ATES, through the realization and monitoring of six ATES pilot plants across five different EU countries. In a preceding paper, based on preliminary results of E-USE(aq), conclusions were already drawn, demonstrating how the barriers for this form of shallow geothermal energy can be overcome, and sometimes even leveraged as opportunities. Based on final pilot project results, key economic and environmental outcomes are now presented. This paper starts with the analysis of specific technological barriers: unfamiliarity with the subsurface, presumed limited compatibility with existing energy provision systems (especially district heating), energy imbalances and groundwater contamination. The paper then shows how these barriers have been tackled, using improved site investigation and monitoring technologies to map heterogeneous subsoils. In this way ATES can cost-efficiently be included in smart grids and combined with other sources of renewable (especially solar) energy, while at the same time achieving groundwater remediation. A comparative assessment of economic and environmental impacts of the pilots is included, to demonstrate the sustainability of ATES system with different renewables and renewable-based technologies. The paper concludes with an assessment of the market application potential of ATES, including in areas with water scarcity, and a review of climate beneficial impact.

Electrically powered buses reduce CO$_{2}$ and noise emissions in urban areas and thus promote the trend towards more livable cities. Upon this reason, more and more cities are introducing their first electrified lines as pilot projects. However, no standardized technology has yet emerged, which is why statements on interactions between vehicle, operation and infrastructure in public transport are proving to be difficult to make. In order to be able to make statistically significant statements in this respect, a simulation model was developed that depicts the three subsystems vehicle, operation and infrastructure. On the basis of measurement data from the PRIMOVE research project in Mannheim, in which an urban bus line is operated with two electrically powered buses, the simulation model was validated and a data basis was laid for further investigations. As a result, simulation studies with more than 700 simulated operating days could be carried out, the results of which represent the input for the following statistical analysis. Based on this analysis, the interactions described above will be demonstrated in the design of the main technical parameters, the battery lifespan and the energy demand of electrical bus lines. Through the findings of these simulations, an optimized version of the already electrified bus line in Mannheim will then be presented. Finally, a novel design methodology for electrification based on a multi-objective optimization is introduced. All parameters of the system are variable in order to apply the presented methodology to other projects and thus underline the general validity of the work.