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Abstract: This paper presents the analysis of the performance of a solar cooling facility along one summer season using a commercial single-effect water–lithium bromide absorption chiller aiming at domestic applications. The facility works only with solar energy using flat plate collectors and it is located at Universidad Carlos III de Madrid, Spain. The statistical analysis performed with the gathered data shows the influence of five daily operational variables on the system performance. These variables are solar energy received along the day (H) and the average values, along the operating period of the solar cooling facility (from sunrise to the end of the cold-water production), of the ambient temperature (), the wind velocity magnitude (V), the wind direction (θ) and the relative humidity (RH). First order correlation functions are given. The analysis of the data allows concluding that the most influential variables on the daily cooling energy produced and the daily averaged solar COP are H, V and θ. The period length of cold-water production is determined mainly by H and . [ABSTRACT FROM AUTHOR]

Abstract: The aim of this paper is to carry out a comparative study with regard to energy consumption and greenhouse gas emissions, in respect of two types of engines with three different fuels. The fuels analysed are diesel, biodiesel 30% (B30) and compressed natural gas (CNG). The engines tested were a spark ignition engine (Otto cycle) and two compression ignition engines (Diesel cycle), the first fed with CNG and the last two with B30 and diesel. What is new about this study is its scope of application concerning refuse collection services in the city of Madrid. The tests were carried out on refuse trucks of the FCC Company along actual urban routes in the city of Madrid. Also taken into account were the energy input and the greenhouse gases emitted for each of the paths taken by the fuels analysed, from resource recovery to delivery to the vehicle tank. [Copyright &y& Elsevier]

• We applied MFA to quantify the future energy recovery potential of MSW. • Future scenarios for the year 2030 were defined for Madrid, Spain. • The gross energy recovery potential of MSW is likely to decrease in the future. • MSW streams susceptible to energy recovery account for 48 – 60% of the MSW. • Recycling targets do not necessarily compromise energy recovery. Rules on separate collection and recycling of municipal solid waste (MSW) can have a significant impact on the waste-to-energy (WTE) industry. Understanding the future energy recovery potential of MSW is therefore paramount to establish the role of WTE technologies in waste management plans. In this study we applied material flow analysis (MFA) to systematically quantify the energy recovery potential of MSW under plausible scenarios for 2030. These scenarios describe structural changes that are expected to affect the energy recovery potential, such as the increase in the separate collection rates and the implementation of more efficient material recovery facilities (MRFs). The assessment was performed for Madrid, Spain, as a case study. The results reveal that the gross energy recovery potential of MSW, i.e. the maximum amount of energy that could be obtained, is likely to decrease in the future mainly due to a higher diversion of plastic, paper, and cardboard to recycling. The gross energy recovery potential of the MSW generated in Madrid by 2030 ranges from 4,963 to 6,984 TJ year−1 according to the scenarios defined in this study. This means a decrease of 34 – 7% compared with 2017. However, the waste streams susceptible to energy recovery –organic waste streams and MRFs' rejects– account for 48 – 60% of the MSW generated under the 2030 scenarios. Furthermore, the electricity generation potential could increase between 8 and 55% by 2030 with respect to 2017 if more efficient incineration and/or gasification facilities are implemented. All in all, our findings clearly suggest that recycling targets do not necessarily compromise energy recovery. [ABSTRACT FROM AUTHOR]