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This paper presents results of an online stated choice experiment on preferences of Dutch private car owners for alternative fuel vehicles (AFVs) and their characteristics. Results show that negative preferences for alternative fuel vehicles are large, especially for the electric and fuel cell car, mostly as a result of their limited driving range and considerable refueling times. Preference for AFVs increases considerably with improvements on driving range, refueling time and fuel availability. Negative AFV preferences remain, however, also with substantial improvements in AFV characteristics; the remaining willingness to accept is on average € 10,000-€ 20,000 per AFV. Results from a mixed logit model show that consumer preferences for AFVs and AFV characteristics are heterogeneous to a large extent, in particular for the electric car, additional detour time and fuel time for the electric and fuel cell car. An interaction model reveals that annual mileage is by far the most important factor that determines heterogeneity in preferences for the electric and fuel cell car. When annual mileage increases, the preference for electric and fuel cell cars decreases substantially, whilst the willingness to pay for driving range increases substantially. Other variables such as using the car for holidays abroad and the daily commute also appear to be relevant for car choice. © 2014 Elsevier Ltd.

In this paper some preliminary experimental results on a Zebra battery based propulsion system for urban bus applications are presented. The tests were carried out using a laboratory 1:1 scale test bench, composed by a 65 kW electric drive, specifically designed for urban bus applications, supplied by two 20 kWh Zebra batteries connected in parallel. The electric power train was tested on a laboratory bench, connected through a fixed ratio gear box to a 100 kW regenerative electric brake provided with speed and torque controls, in order to evaluate the propulsion system performance in steady state operative conditions. The obtained preliminary experimental results were utilized to implement a Matlab-Simulink model of urban bus, which might be powered by the same electric propulsion system studied. Thanks to this model it was possible to evaluate the dynamic behavior of the urban bus, working on standard driving cycles, taking into account the resistant forces represented by proper vehicle/road/aerodynamic parameters. An evaluation of the expected real vehicle driving range was also estimated in different road conditions.

Hot water heat stores with stratification are a common technology used in solar energy systems and reuse of waste heat. Adding a PCM module at the top of the water tank would give the system higher storage density, and compensate heat loss in the top layer. The work presented here includes experimental results and numerical simulation of the system using an explicit finite-difference method. Experiments and simulations were carried out using different cylindrical PCM modules. With only 1/16 of the volume of the store being PCM, 3/16 of water at the top of the store was held warm for 50% to 200% longer and the average energy density was increased by 20% to 45%. Furthermore, these 3/16 of water were reheated by the heat from the module after being cooled down in only 20 min.

Wood biomass is turned into industrial fuel through chipping. The efficiency of chipping depends on many factors, including chipper knife wear. Chipper knife wear was determined through a long-term follow-up study, conducted at a waste wood recycling yard. Knife wear determined a sharp drop of productivity (>20%) and a severe decay in product quality. Dry sharpening with a grinder mitigated this effect, but it could not replace proper wet sharpening. Increasing the frequency of wet sharpening sessions determined a moderate increase of knife depreciation cost, but it could drastically enhance machine performance and reduce biomass processing cost. Since benefits largely exceed costs, increasing the frequency of wet sharpening sessions may be an effective measure for reducing overall chipping cost. If the main goal of a chipper operator is to increase productivity and/or decrease fuel consumption, then managing knife wear should be a primary target. (C) 2014 Elsevier Ltd. All rights reserved.

Clean combustion technologies, based on reactant dilution, have shown very peculiar and innovative characteristics. Reduction of light and noise emission and uniformity of temperature and composition distribution inside the combustion chamber, related to an extension of the reaction zone, make these processes very promising in several technological fields. Analysis of combustion in very diluted conditions is needed for a general understanding of these processes, which remain unknown from many aspects. The study is also useful for the identification of practical constraints which define the most suitable reactor configurations and working parameters for process reliability. The present work deals with a theoretical analysis of methane oxidation in diluted conditions using one of the detailed kinetic schemes available in the literature. A well-stirred reactor (WSR) configuration has been considered as a first attempt of process schematization. This choice is consistent with the experimental characterization of the flameless combustion processes. The influence of residence time, C/O ratio, and inlet temperature on the steady state was studied for an oxygen molar fraction (0.05), chosen as representative of flameless combustion processes. It has been pointed out that only rich conditions (C/O ? 0.25) are possible for WSR creation, because they allow partial methane conversion. Three kinetic regimes, related to different temperature ranges, have been identified on the basis of product distribution analysis. Both the oxidation and pyrolitic regimes, occurring respectively in low- and high-temperature ranges, are the most interesting working conditions for diluted combustion. The former, leading to CO and H2O as main reaction products, is suitable for reburning technology. The latter, which corresponds to large production of CO and H2, has been shown to be a reasonable explanation of flameless combustion. Advantages and potentials of this innovative process are analyzed, taking into account the kinetic pathway followed in the different working conditions.

Abstract In recent years, the overall energy consumption is increasing significantly and the energy consumption in the building sector represents over 30% of the global ones in developed countries. Thermal energy storage (TES) using phase change materials (PCM), which are materials able to store high amounts of energy as latent heat, is suggested as a possible solution to decrease the energy consumption. The authors of this paper developed materials able to encapsulate/stabilize PCM in addition to isolate an industrial residue from the steel recycling process: electrical arc furnace dust (EAFD). This waste is a hazardous dust, and when it is combined with a polymeric matrix produce dense sheet materials suitable for multilayered constructive systems. In this paper the physical, mechanical, thermal and acoustical characterization of two new materials with EAFD and PCM in a polymeric matrix for constructive system is presented. The results are compared with those obtained for one commercial dense sheet material available in the market, Texsound commercialized by TEXSA (Spain). The new dense sheet materials developed in this paper have similar acoustic properties compared to the results obtained for the commercial material and are competitive with it, even better because the new material incorporates PCM which increases the thermal inertia of final constructive system.

Stories play an exceptionally important role in how people assign value to a place. Taken together, all those stories essentially give a place an identity. The aim of placemaking is to ensure that the people using a place can appreciate that place. Placemaking approaches are focussed on strategic interventions in a place and aimed at changing the meaning and value of that place for local people, thus creating a qualitative place for enhanced storytelling. Using greenery is a common approach in place-making. Urban greenery has gone through a process of emancipation in the past 15 years. This emancipation has led to awareness that urban greenery is about more than just ecology and biodiversity, but also has social and economic consequences for a city’s fortunes. It is clear that green spaces do not stand alone: they are part of a complex urban system, and the use of green spaces in this complex system has immediate repercussions for how the city functions. With the changing role of green spaces within cities, the need to manage these spaces is emphasized. In this sense, the place-making approach, along with the storytelling approach could provide valuable insight on the planning and management of green spaces within the urban environment, with the aim to enhance quality of life by means of the social connection between people, the users of the space, and the qualitative place provided. This research illustrated that green space managers would need more social and organizational skills to manage modern urban green spaces in an attempt to create qualitative, usable spaces for citizens, spaces that are built upon stories and spaces that would further enable future stories of citizen life. The Story Behind the Place: Creating Urban Spaces That Enhance Quality of Life (PDF Download Available). Available from: https://www.researchgate.net/publication/271918395_The_Story_Behind_the_Place_Creating_Urban_Spaces_That_Enhance_Quality_of_Life [accessed Dec 21, 2015].

The incorporation of recycled materials in concrete as a partial replacement of cement is becoming an alternative strategy for decreasing energy-intensive and CO2 emissions imputable to the cement manufacture, while investigating new potential uses of such multifunctional materials for environmental sustainability opportunities. Therefore, low-cost and worldwide availability of by-products materials is being assessed for sensible heat thermal energy storage applications based on cementitious materials. A greater concern is especially required focusing on the thermal stability of cement paste under high temperature cycled conditions. Moreover, compatibility between cement type and supplementary cementitious materials is determinant for the proper performance reliability. In this study, benchmark cement types were selected, i.e., ordinary Portland and calcium aluminate. Six supplementary cementitious materials were added to both types of cement in a content of 10 % and 25 %. Thermo-mechanical properties were studied before and after 10 thermal cycles from 290 to 650 ◦C. Results after thermal cycling showed that calcium aluminate cement paste mixtures maintained their integrity. However, most ordinary Portland cement paste mixtures were deteriorated: only mixtures with 25 % cement replacement with chamotte, flay ash, and ground granulated blast furnace slag remained without cracks. Calcium aluminate cement paste mixtures obtained the highest compressive strength, for partial replacement of cement with 10 % of chamotte, ground granulated blast furnace slag, and iron silicate. The incorporation of supplementary cementitious materials did not increase the thermal conductivity. This work was partially funded by the Ministerio de Ciencia, Innovación y Universidades de España (RTI2018-093849-B-C31 - MCIU/AEI/FEDER, UE) and by the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) (RED2018-102431-T). The authors at University of Lleida would like to thank the Catalan Government for the quality accreditation given to their research group (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme and by the Italian project ‘SOS-CITTA’ supported by Fondazione Cassa di Risparmio di Perugia under grant agreement No 2018.0499.026. Laura Boquera acknowledgments are due to the PhD school in Energy and Sustainable Development from University of Perugia. Laura Boquera would like to acknowledge the financial support provided by UNIPG – CIRIAF InpathTES project. The authors also thank the companies that provided the material to make possible this experimental research: Arciresa, Abrasivos Mendiola EDERSA—Masaveu Industria, General Admixtures S.p.A, Mapei, Ciments Molins industrial, and Promsa for the material supplied in this research. Financial support of the UNIPG-CIRIAF team has been achieved from the Italian Ministry of University and Research (MUR) in the framework of the Project FISR 2019: “Eco Earth” (code 00245) and it is gratefully acknowledged.

Abstract Thermal energy storage systems for both heat and cold are necessary for many industrial processes. High energy density and high power capacity are desirable properties of the storage. The use of latent heat increases the energy density of the storage tank with high temperature control close to the melting point. Tube in PCM tank is a very promising system that provides high packing factor. This work presents an experimental study of a PCM tank for cold storage applications. Two different configurations and different flow rates of the heat transfer fluid were studied. The effectiveness of the PCM storage system was defined as that of a heat exchanger. The results showed that the heat exchange effectiveness of the system did not vary with time, decreased with increasing flow rate and increased with increasing heat transfer area. The effectiveness was experimentally determined to only be a function of the ratio m ˙ /A. This equation was found to be adequately be used to design a PCM storage system, and a case study is presented. It was shown that the tube in tank design together with a low temperature PCM is suitable as a thermal storage facility for cold storage.