High energy efficiency retrofit module development

One of the main key sectors where it is vital to reduce the energy consumption, is the existent building stock. The European Union has recognized this issue in 2002 with the entrance into force of the Directive on Energy Performance of Buildings where important measures to limit the buildings primary energy consumption are foreseen. Within this context, it was initiated a new project focusing the development of a new retrofit solution – a prefabricated façade retrofit module. This solution is, to some extent, a by-product of the authors’ participation on the International Energy Agency project IEA ECBCS Annex50 and on the FCT funded project PTDC/ECM/67373/2006. In order to achieve a better support for the design of the solution and for the module thermal optimization, there were applied some computational tools like Google SketchUp® for 3D modelling to test the design options and eQuest® tool for energy performance prediction of several construction options and to assure their accordance with the applicable regulations. At the moment, a prototype is being developed and built in the Test Cells of University of Minho in order to carry out several “in-situ” thermal performance measurements.iiSBE Portugal, Universidade do Minho, Instituto Superior Técnico, cib, UNEP, InCI, STAP, FCT, IRHU, CIN, Soares da Costa, DST, CASAIS, energypark, SECIL, CIMPOR, Turismo de Portugal Algarv

High Energy Efficiency in Building Construction

В данной статье рассматривается вопрос достижения классов высокоэнергоэффективных домов, поскольку тема экономии была и будет всегда актуальной не только в Республике Беларусь, но и за ее пределами. Любое здание ежеминутно теряет определенное количество теплоты, а высокоэнергоэффективные здания способствуют минимализации этих потерь.This article discusses the issue of achieving classes of highly energy efficient houses, since the topic of saving has been and will always be relevant not only in the Republic of Belarus, but also abroad. Any building loses a certain amount of heat every minute, and highly energy efficient buildings help to minimize these losses

Exact and heuristic allocation of multi-kernel applications to multi-FPGA platforms

FPGA-based accelerators demonstrated high energy efficiency compared to GPUs and CPUs. However, single FPGA designs may not achieve sufficient task parallelism. In this work, we optimize the mapping of high-performance multi-kernel applications, like Convolutional Neural Networks, to multi-FPGA platforms. First, we formulate the system level optimization problem, choosing within a huge design space the parallelism and number of compute units for each kernel in the pipeline. Then we solve it using a combination of Geometric Programming, producing the optimum performance solution given resource and DRAM bandwidth constraints, and a heuristic allocator of the compute units on the FPGA cluster.Peer ReviewedPostprint (author's final draft

High energy efficiency ventilation to limit COVID-19 contagion in school environments

This study investigates the possibility to contain COVID-19 contagion in indoor environments via increasing ventilation rates obtained through high energy efficiency systems combining thermal recovery by heat exchanger and thermodynamic recovery by heat pump. The starting point of this assessment is a procedure to evaluate in naturally ventilated environments, the current infectious risk by using measurements of indoor/outdoor CO2 concentrations to calculate actual air changes per hour. The method was applied to some typical school environments in Italy. The results indicated very infectious situations with reproduction number Ro values up to exceed 13. But, the simulations assessed an extraordinary reduction of indoor viral concentration and consequently of the infection risk by a strong mechanical ventilation. High ventilation rates make facemasks effective even with use levels (from 50%) reasonable also for pupils. This way, R0 goes down the value one. As regards energy performance, the behavior of an autonomous high efficiency air handling unit (HEAHU), to be installed in an existing naturally ventilated classroom, was simulated in the monitored days. The results highlight the ability to achieve a reduction in energy consumption between 60% and 72%

Energy-Efficient Future Wireless Networks: A Marriage between Massive MIMO and Small Cells

How would a cellular network designed for high energy efficiency look like? To answer this fundamental question, we model cellular networks using stochastic geometry and optimize the energy efficiency with respect to the density of base stations, the number of antennas and users per cell, the transmit power levels, and the pilot reuse. The highest efficiency is neither achieved by a pure small-cell approach, nor by a pure massive MIMO solution. Interestingly, it is the combination of these approaches that provides the highest energy efficiency; small cells contributes by reducing the propagation losses while massive MIMO enables multiplexing of users with controlled interference.Comment: Published at IEEE Workshop on Signal Processing Advances in Wireless Communications (SPAWC 2015), 5 pages, 5 figure