• Energy Research

© 2016. This version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This paper presents the results of a detailed method for developing cost-optimal studies for the energy refurbishment of residential buildings. The method takes part of an innovative approach: two-step evaluation considering thermal comfort, energy and economic criteria. The first step, the passive evaluation, was presented previously [1] and the results are used to develop the active evaluation, which is the focus of this paper. The active evaluation develops a cost-optimal analysis to compare a set of passive and active measures for the refurbishment of residential buildings. The cost-optimal methodology follows the European Directives and analysed the measures from the point of view of non-renewable primary energy consumption and the global costs over 30 years. The energy uses included in the study are heating, domestic hot water, cooling, lighting and appliances. In addition, the results have been represented following the energy labelling scale. The paper shows the results of a multi-family building built in the years 1990–2007 and located in Barcelona with two configurations: with natural ventilation and without natural ventilation. The method provides technical and economic information about the energy efficiency measures, with the objective to support the decision process.

The building sector is among the largest energy users while offering cost-effective means of reducing energy use. Dynamics of energy efficiency improvements in the building stock are very slow due to the long life span of buildings and barriers such as high investment cost. A list of general policy measures to overcome the barriers to energy efficiency improvements in the Mediterranean (MED) area was proposed by regional experts in the framework of the MARIE project. These measures could be considered as a first draft of the MED buildings energy efficiency strategy. This study assesses the potential impacts of such measures, so as to inform on their effectiveness. The MARIE measures result in larger energy savings than an equally ambitious strategy based on ‘conventional measures’. However, the benefits of MARIE arrive slowly and show large variations among regions depending on the characteristics of their current building stock.

This paper presents a detailed method to develop cost-optimal studies for the energy renovation of residential buildings. A realistic characterization of the building has been introduced, using measurement and survey data. The method allows improving the interaction between the occupancy and the building,and the characterization of the real state of the construction. In addition, the building simulation includes vernacular strategies of the Mediterranean architecture, as for example the natural ventilation and theuse of solar protection. The method presented takes part of an innovative approach: two-step evaluation considering thermal comfort, energy and economic criteria. The passive evaluation is the focus of the paper and evaluates the passive measures from an economic and thermal comfort point of view. This method prioritizes the passive measures rather than the active ones, considering the thermal comfort of the users as a criterion of decision. The paper shows the results of a multi-family building built in the years 1990–2007 and located in two climates C2 and B3 (Barcelona and Tarragona). The method provides technical and economic information about a set of passive energy efficiency measures, with the objective to help to make decisions for choosing the appropriate combination of passive measures. Peer Reviewed

Thermal mass of buildings and domestic hot water tanks represent interesting sources ofthermal energy storage readily available in the existing building stock. To exploit them to their full potential,advanced control strategies and a coupling to the power grid with heat pump systems represent the mostpromising combination. In this paper, model predictive control (MPC) strategies are developed and tested ina semi-virtual environment laboratory setup: a real heat pump is operated from within a controlled climatechamber and coupled with loads of a virtual building, i.e., a detailed dynamic building simulation tool.Different MPC strategies are tested in this laboratory setup, with the goals to minimize either the deliveredthermal energy to the building, the operational costs of the heat pump, or the CO2emissions related to theheat pump use. The results highlight the ability of the MPC controller to perform load-shifting by chargingthe thermal energy storages at favorable times, and the satisfactory performance of the control strategies isanalyzed in terms of different indicators, such as costs, comfort, carbon footprint, and energy flexibility. Thepractical challenges encountered during the implementation with a real heat pump are also discussed andprovide additional valuable insights Peer Reviewed

With the current movement towards Net Zero Energy Buildings (Net ZEBs) decisions regarding energy carrier weighting factors will have implications on which technologies could be favoured or disfavoured, and therefore adopted or not adopted, in the building sector of the near future. These implications should be taken into consideration by policy makers when developing legislation and regulations addressing the building sector. A parametric analysis was conducted on six buildings in Europe of different typologies and climates in order to assess how different weighting factors would impact the choice of technical systems to be installed. For each combination the amount of PV capacity necessary to achieve a net zero balance has been calculated and used as the main indicator for comparison; where less PV area means more favourable condition. The effect of including a solar thermal system is also discussed. With the current European national weighting factors, biomass boiler is largely the preferred solution, frequently achieving the balance with PV installed on the roof, while gas boiler is the most penalized. The situation changes when strategic weighting factors are applied. Lower weighting factors for electricity and district heating, e.g. reflecting national targets of increased penetration of renewables in such grids, would promote the use of heat pump and district heating, respectively. Asymmetric factors aimed at rewarding electricity export to the grid would facilitate the achievement of the zero balance for all technologies, promoting cogeneration in some cases. On the contrary, low weighting factors for electricity, e.g. reflecting a scenario of high decarbonisation of the power system, prove quite demanding; only few technical solutions would be able to reach the balance within the available roof area for PV, because of the low value credited to exported electricity. In this situation, the preferred solution would be heat pumps combined with solar thermal. In addition, the choice of weighting factors and the resulting favoured technologies will determine the temporal matching of load and generation. While all-electric solutions tend to use the grid as seasonal storage, other solutions will have a yearly net export of electricity to the grid to compensate for the supply of other (thermal) energy carriers. Therefore, it is important to consider the implications for the electricity grid resulting from the choice of weighting factors. (C) 2014 Elsevier B.V. All rights reserved. (Less)

Identifying the parameters of grey-box models requires enough data collected from sensors installed inside and outside of the building for long enough period of time. Consequently, this process is time consuming, costly especially in large buildings that require more sensors, and can only be conducted after the building is constructed. This paper introduces a procedure for identifying greybox models from white-box models. Following this procedure, grey-box models can be identified using data generated by a white-box model, without any requirement for mounting sensors in a building. This reduces the cost and time of modelling, control design and prediction. The introduced procedure is utilized to find a grey-box model of the heat dynamics of a four-floor building in Spain. Simulation results demonstrate the effectiveness of this procedure.

Abstract Purpose The effect of heat waves on mortality is well known, but current evidence on morbidity is limited. Establishing the consequences of these events in terms of morbidity is important to ensure communities and health systems can adapt to them. Methods We thus collected data on total daily emergency hospital admissions, admissions to critical care units, emergency department admissions, and emergency admissions for specific diagnoses to Hospital Universitario de Son Espases from 1 January 2005 to 31 December 2021. A heat wave was defined as a period of ≥ 2 days with a maximum temperature ≥ 35 °C, including a 7 day lag effect (inclusive). We used a quasi-Poisson generalized linear model to estimate relative risks (RRs; 95%CI) for heat wave-related hospital admissions. Results Results showed statistically significant increases in total emergency admissions (RR 1.06; 95%CI 1 – 1.12), emergency department admissions (RR 1.12; 95%CI 1.07 – 1.18), and admissions for ischemic stroke (RR 1.26; 95%CI 1.02 – 1.54), acute kidney injury (RR 1.67; 95%CI 1.16 – 2.35), and heat stroke (RR 18.73, 95%CI 6.48 – 45.83) during heat waves. Conclusion Heat waves increase hospitalization risk, primarily for thromboembolic and renal diseases and heat strokes.