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- O novo RCCTE: Estratégias e medidas para a sua verificaçãoPublication . Goncalves, Helder; Horta, Cristina; Ramalho, Álvaro; Camelo, Susana; Graça, João Mariz
- Evolução do Regulamento das Características de Comportamento Térmico dos Edifícios (RCCTE): Caso de EstudoPublication . Camelo, Susana; Horta, Cristina; Ramalho, Álvaro; Graça, João Mariz; Goncalves, HelderNesta apresentação faz-se a aplicação, para um mesmo apartamento, do Regulamento das Características do Comportamento dos Edifícios (RCCTE) apresentando em paralelo as metodologias preconizadas nas versões do RCCTE de 1990e de 2006. A análise incide num apartamento de tipologia T1 de um Edifício localizado na cidade de Lisboa (zona climática I1-V2 Sul). O apartamento T1-A constitui uma única zona independente (RCCTE-1990) / fracção autónoma (RCCTE 2006). A caracterização térmica da envolvente para aplicação do RCCTE foi feita com base nas dois documentos do LNEC ITE 28 e ITE 50, respectivamente para o RCCTE de 1990 e para o RCCTE de 2006. Procurar-se-á relativizar o peso dos diferentes elementos da envolvente em termos das perdas e dos ganhos e por fim estimar, para ambas as versões, as necessidades nominais de energia útil para aquecimento e arrefecimento e, para a versão de 2006 ainda as necessidades nominais de energia útil para produção de água quente sanitária e de energia primária.
- Solar XXI building PV systems: performance during the first two yeras of operationPublication . Rodrigues, Carlos; Viana, Susana; Joyce, A; Goncalves, Helder; Silva, António Rocha eThe purpose of this paper is to present the results obtained in the first two years of operation of the grid-connected photovoltaic (PV) systems installed in the named “Solar XXI” building. One PV system, made with multicrystalline silicon modules, has a peak power of 12 kW and was installed on the façade; another system made with amorphous silicon modules has a peak power of 6 kW and was installed in the surrounding park area near the building. From 1st February 2006 until 31 July 2008, the measured daily average, of the building electrical energy consumption, was about 75 kWh and the two PV systems produced in average about 72 % of this energy. The averaged measured Performance Ratio of the systems was about 0.84 for the PV Façade and about 0.76 for the PV in the Park.
- A multi-interface software designed to share geometries within different simulation toolsPublication . Graça, João Mariz; Bento, João; Goncalves, HelderA computer system that consists of a set of several programs that share both the same geometric definition and a consistent set of definitions for construction elements, is under development. The system consists of a common program allowing different types of exportation to other simulation programs or to other modules. The main modules under development until now are: an interface to the Energy Plus program, which builds an "idf" file from a 3D geometric definition that was previously modeled in graphical mode; and a module, that will provide the necessary calculations to verify if a given shape fulfills the thermal regulation of buildings which is based upon the Energy Performance of Buildings Directive (EPBD) approved by European Parliament and Council. An interface with Radiance program is also being developed. Using this system, which has been designed firstly for architectural conception, the user can perform different simulations with different aims, but sharing the same architectural shape and construction types, in order to check if the building fulfills thermal Portuguese codes and to perform energy simulations with Energy Plus or Radiance. The use of this system has demonstrated that it can represent a great saving of time in simulations and helping to reduce the occurrence of design errors as well. Since it allows performing simulations in a very quick way it can contribute also to help architects on achieving better solutions while designing, in terms of the optimization of all the parameter evaluated. The use of energy plus to evaluate the comfort of the buildings while being design as shown that this methodology can help to find more sustainable solutions in terms of their architectural shape and construction elements.
- Fórum Energias Renováveis em Portugal 2020Publication . Goncalves, Helder; Ponce Leao, Maria TeresaRESUMO: O Plano Nacional Energia e Clima é o principal instrumento de política energética e climática nacional, para a década 2021-2030, rumo a um futuro neutro em carbono, definindo as políticas de atuação a médio prazo para o objetivo da neutralidade carbónica em 2050. Nesta fase de transição energética é necessária uma análise cuidada das várias tecnologias existentes e emergentes, que possam contribuir para a descarbonização do sistema energético, de forma equilibrada e sustentável. Mais importante que as medidas em cada tecnologia é a sua integração em todo o sistema energético, de forma a tirar partido das sinergias entre as várias tecnologias e as diferentes utilizações finais e assim promover um equilíbrio e mais valia para todos. O atual cenário da energia (renovável) em Portugal teve o seu início no final do século XX e imprimiu uma profunda alteração no sistema energético, principalmente no setor elétrico, sobretudo devido à importância das centrais eólicas. A perspetiva do PNEC é que se verifique um grande investimento no aproveitamento em larga escala da energia solar fotovoltaica, ao mesmo tempo que outras tecnologias se tornam promissoras e competitivas, como é o caso da energia solar de concentração, ou mesmo da energia eólica offshore. Para além destas fontes renováveis, a biomassa constitui um importante recurso renovável cujo contributo importa discutir em termos futuros, quer no âmbito da bioenergia, quer no seu sentido mais lato, a bioeconomia. Adicionalmente, os consumidores começam a assumir um papel ativo, quer em termos de opções de mercado, quer no que respeita a opções de autoprodução, na qual a opção pelo veículo elétrico e pelo armazenamento (elétrico e térmico), terá um papel instrumental na gestão de um futuro sistema elétrico, tendencialmente 100% renovável. O Fórum Energias Renováveis em Portugal 2020 foi organizado, sob coordenação do LNEG, com a constituição de diferentes grupos de trabalho com a participação da comunidade da energia - indústria, investidores, empresas, academia e instituições de investigação, e consumidores finais, onde se debateram temas específicos do setor energético e das energias renováveis, nomeadamente: o futuro do setor elétrico e como se poderão atingir os objetivos de uma maior integração de energias renováveis; as energias renováveis no setor dos transportes; as energias renováveis para calor e frio, no contexto das cidades do futuro e nos setores industrial e agrícola; o novo papel dos consumidores e dos consumidores/produtores (prosumers). Foram realizados seminários setoriais e um seminário final, em maio de 2019, para apresentação pública das conclusões. Foi ainda elaborada uma súmula de contributos, submetida no processo de consulta pública realizada pela Direção Geral de Energia e Geologia, no âmbito o PNEC 2030. Neste documento, estão publicados capítulos independentes e com autoria distinta, por tema, e uma síntese das principais reflexões /conclusões dos trabalhos de cada grupo, a saber: Biocombustíveis, Energia Eólica, Energia Solar (térmica e fotovoltaica) e Energias Renováveis e Integração no Sistema Energético. Em “Anexos” são divulgadas as apresentações públicas efetuadas no âmbito do Fórum.
- Solar XXI : em direcção à energia zero : towards zero energyPublication . Goncalves, Helder; Cabrito, Pedro; Diniz, Isabel
- A integração de energias renováveis nos edifícios "Conceito de NZEB e Smart Cities"Publication . Goncalves, Helder; Aelenei, Laura Elena
- Towards a strategy to zero energy buildings (ZEB) conceptPublication . Goncalves, HelderThe energy consumption in buildings and the need for its reduction has been since the late 60’s and 70ś a main question among professionals (designer, architects, and engineers), legislators and users around the word. Reduction in energy demand for heating for instance was implemented in the so called Solar Buildings (with reduction of 70 to 80% in the heating demand). The building regulation start putting targets, in the overall annual energy consumption xx kWh/m2 year, and some achieve the level of standards, imposing very low values, such as Passivhaus standard which fundamentally consists of an energy limit (net useful energy demand for heating of 15 kWh/m²/year and a total primary energy consumption of 120 kWh/m²/year). Now we are dealing for a new concept, in which those values approach zero (ZEB) or even minus, which correspond to building which produce more than what they spend (ENERGY PLUS BUILDINGS). This paper discusses some of the main issues regarding the strategy to achieve some of these goals in the future.
- Os edifícios bioclimáticos e a integração das energias renováveis e os sistemas energéticos : Livro de apresentações do seminárioPublication . Goncalves, Helder; Camelo, Susana
- The keep Cool II idea and strategy: from "cooling" to "sustainable summer comfort"Publication . Camelo, Susana; Goncalves, Helder; Laia, Carlos; Richard, M.The European Energy Performance of Buildings Directive (EPBD) explicitly refers to a "passive cooling techniques, primarily those that improve indoor climatic conditions and the microclimate around buildings". However, in Europe the demand for air conditioning is rising, especially in office buildings and is expected that the cooled floor area will be four times higher in 2020 when compared with 1990 figures. About 40% of our energy use is consumed in buildings and air conditioning represents a significant part. he overcome this problem conventional answer consists on to improve of the energy efficiency of cooling. However, this startegy showed limited results in terms of saving energy and reducing greenhouse gas emissions. In fact, cooling can be avoided (or the need to use energy for cooling) or significantly reduced without risking summer thermal comfort for building occupants, having thus the potential to achieve substantial reductions in energy demad and contributing to the overall objective of reduction CO2 emissions, minimizing the risk of the global warming and of the European climate protection commitments. This paper presents the conclusions of two surveys undertaken in the frame work of the Keep CoolII Project. One centered on evaluating current practices in cooling design, construction and operation, in order to obtain a feel of how widely good practices are known and use and as a basis for the subsequent study on incentives to remedy a set of key barriers and to reach the notion of summer comfort as a service. Indeed, efficient strategies for cooling have been studied for at least two decades, and several campaigns have already been implemented in the EU member states to disseminate knowledge on summer comfort efficiency since the 1990s. The other survey was undertaken in order to review the energy efficency criteria, in the national buildings codes, concerning summer comfort or mechanical cooling system in order to elaborate recommendations towards a sustainable summer comfort. This surver intended update, in a regional basis, the information regarding national building regulations, identifyin the measures adopted and delineating good practices concerning energy consumption, summer comfort and summer requirements. Finnaly, it should be stressed out the key role of the building designer towards sustainable summer comfort. Building codes requirements and design rules needs a proper use by the building designer.