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This paper deals the study of the lead-acid behavior and its modelling based on the Kinetic Battery Model. Results of experimental tests are used to realize the analysis and to estimate the model parameters. These last can serve for prediction and estimation of the battery lifetime according to the actual operating conditions.

Abstract The combined production of electricity, heat and cold by a polygeneration system connected to a district heating and cooling network can provide high energy utilization efficiency. The inherent complexity of simultaneous production of different services and the high variability in the energy demand make combined cooling and heating systems performance highly dependent on the operational strategy. In this paper, an operational optimization method based on the moving average of real-time measurements of energy demands and ambient conditions is proposed. Real energy demand data from a district heating and cooling network close to Barcelona, Spain, are used to test the method. A complex polygeneration system is considered, consisting of an internal combustion engine, a double-effect absorption chiller, an electric chiller, a boiler and a cooling tower. A detailed modelling of the system is provided, considering partial load behavior of the components and ambient conditions effects. Results of the real-time optimal management are discussed and compared to traditional operational strategies and to the ideal optimal management achievable with perfectly accurate forecast of energy demands. Moreover, the optimal width of the window adopted for the moving average of real-time data is identified.

Light sources are being competitive in the current market. Several types of these products have been widely used in the last two decades. They play a major role on the low voltage network as they produce and inject undesired noise onto the transmission lines of the PLC channel. This noise can be of a serious and negative effect when using the power line communications system to control the automatic switching of lamps in residential areas and public places. The main colour low energy indoor light sources that exist in the market, such as, LEDs and CFLs have been tested for the noise generation on the PLC channel and the results are analyzed and shown in this study. A mathematical analysis of LED bridge rectifier is introduced in this study.

Abstract The 21st Conference of the Parties (COP21) of the United Nations Framework Convention on Climate Change (UNFCCC) marked a milestone in the course of international efforts on global climate action. As part of the COP21 side events, on December 4th the Lima Paris Action Agenda presented a half-day of presentations and round table discussions titled Focus on Private Finance. The event was supported by the Secretary-General of the United Nation, Caisse des Depots, and the I4CE Institute for Climate Economics. This conference report summarizes the findings of the session and the messages delivered by finance industry representatives. Significant investment in low carbon assets is required to maintain global temperature increases below 2 °C. The two resounding themes throughout the session were that in order to attract capital for low carbon investments fossil fuel subsidies must end and a higher carbon price is needed to incentivise investment. Furthermore, accounting and regulatory bodies need to implement more stringent disclosure and reporting requirements so that climate risk is properly understood by investors. There is significant appetite for investment in the low carbon sector which is demonstrated by the growth in the green bond market. Financial institutions have a role to play in aggregating, structuring and de-risking investments to facilitate private finance investment. Policy makers also need to improve the investment environment by creating consistent and stable long term policies which will give investors' confidence.

The EU has long pursued relatively ambitious climate and energy policies, often against the backdrop of what has been termed the EU ‘polycrisis’. This paper introduces a special issue which seeks t...

As a consequence of energy issues and societal dilemmas, building insulation like the eco-block technology has proven its usefulness to reduce greenhouse gas emissions, improve energy security and enhance the living conditions of building occupants. In Mauritius, the eco-block building material was introduced to improve the energy efficiency of conventional buildings. As observed, limited people's knowledge, poor communication with developers and lack of support from policymakers slow the adoption of the building technology. Mauritian residents are the important stakeholders as they are the final decision-makers of the building insulation. Given recent studies reported that green building adoption is rather psychological than technical, the research makes an original contribution to the literature by extending two consistent psychological frameworks (technology of acceptance model and theory of planned behaviour) and proposing a new framework for assessing the unexplored predictors on eco-block building adoption. A survey questionnaire was forwarded to Mauritian residents through the purposive sampling method to collect data, where 283 responses were useful to undergo structural equation modelling. The results disclosed that attitudes, perceived usefulness, social norm, perceived behavioural control, personal innovativeness, energy concern and price sensitivity have an impact on the acceptance of the eco-block building. Contrarily, subjective knowledge and organisational trust have no influence on the adoption intention. Instead, organisational trust affects behavioural intention indirectly through perceived usefulness. The outcome of this research can serve as a roadmap for relevant stakeholders to promote eco-block building usage in Mauritius.

Mismatching operating conditions affect the energetic performance of PhotoVoltaic (PV) systems because they decrease their efficiency and reliability. The two different approaches used to overcome this problem are Distributed Maximum Power Point Tracking (DMPPT) architecture and reconfigurable PV array architecture. These techniques can be considered not only as alternatives but can be combined to reach better performance. To this aim, the present paper presents a new algorithm, based on the joint action of the DMPPT and reconfiguration approaches, applied to a reconfigurable Series-Parallel-Series architecture, which is suitable for domestic PV application. The core of the algorithm is a deterministic cluster analysis based on the shape of the current vs. voltage characteristic of a single PV module combined with its DC/DC converter to perform the DMPPT function. Experimental results are provided to validate the effectiveness of the proposed algorithm and to demonstrate evidence of its major advantages: robustness, simplicity of implementation and time-saving.

Hybrid electric propulsion in the aviation field is becoming an effective alternative propulsion technology with potential advantages, including fuel savings, lower pollution, and reduced noise emission. On the one hand, the aeroengine manufacturers are working to improve fuel consumption and reduce pollutant emissions with new combustion systems; on the other hand, much attention is given to reducing the weight of the batteries increasing the energy density. Hybrid electric propulsion systems (HEPS) can take advantage of the synergy between two technologies by utilizing both internal combustion engines (ICEs) and electric motors (EMs) together, each operating at their respective optimum conditions. In the present work, some numerical investigations were carried out by using a zero-dimensional code able to simulate the flight mission of a turboprop aircraft, comparing fuel consumption and pollutant emissions of the original engine with other two smaller gas turbines working in hybrid configuration. An algorithm has been implemented to calculate the weight of the batteries for the different configurations examined, evaluating the feasibility of the hybrid propulsion system in terms of number of non-revenue passengers.

Abstract District heating dynamic models arise as an alternative approach to in-situ experimental investigations. The main advantage of dynamic modeling and simulation is the possibility to avoid technical and operational risks that might occur during in-situ experimental investigations (e.g. heat demand is not met, damages in the energy systems etc.). Within this study, the authors present two models for an existing district heating system in Cottbus, Germany. One model is developed using the tool EBSILON Professional, while the other one is developed using the Simscape toolbox for physical modeling in Matlab/Simulink. The models were experimentally validated against measured data from the considered district heating system. The results show that the Simscape model has a better fit and better response than the EBSILON model. Yet, some discrepancies were found between the measured and the simulated data and, therefore, the uncertainties of the models were addressed. A comparative study between both tools is presented. The EBSILON models permit only unidirectional flow, whereas the Simscape toolbox permits reverse flow. Nevertheless, the EBSILON model outperforms the Simscape model in computation time. In addition, this study presents an approach for dynamic thermo-hydraulic modeling of district heating networks. This approach is utilized to examine the role of district heating networks as heat storage as an optimization configuration. The numerical results show less start-ups for additional heat sources. Yet, higher heat losses from the network are observed due to the installation of unburied pipelines.