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- An Eco-Energetic Performance Comparison of Dehumidification Systems in High-Moisture Indoor EnvironmentsPublication . Santos, Alexandre Fernandes; Gaspar, Pedro Dinis; Souza, Heraldo; Caldeira, João M. L. P.; Soares, Vasco N. G. J.This study discusses the choice of dehumidification systems for high-moisture indoor environments, such as indoor swimming pools, supported by an eco-energetic performance comparison. Initially, the causes of the high relative humidity and condensation in these spaces are reported, as well as the available dehumidification technologies. Two different solutions are described: desiccant wheel dehumidification and re-cooling. The energy demand required by a refrigeration system is lower than the desiccant wheel; however, the former system requires less maintenance and does not require refrigerant fluid. An eco-energetic comparison is performed between the two systems in two countries with different energy matrices (Brazil and USA). In Brazil, the desiccant wheel is the best choice for the past 10 years, with a predicted 351,520 kgCO2 of CO2 emissions, which is 38% lower than the refrigeration system. In the USA, the best option is the refrigeration system (1,463,350 kgCO2), a 12% more efficient option than desiccant wheels. This model can be considered for energy and CO2 emissions assessment, predicting which system has better energy efficiency and lower environmental impact, depending on the refrigerant type, location and environmental conditions.
- Ecoenergetic Comparison of HVAC Systems in Data CentersPublication . Santos, Alexandre F.; Gaspar, Pedro Dinis; Souza, Heraldo J. L. deThe topic of sustainability is of high importance today. Global efforts such as the Montreal Protocol (1987) and the Kigali Amendment (2016) are examples of joint work by countries to reduce environmental impacts and improve the level of the ozone layer, the choice of refrigerants and air conditioning systems, which is essential for this purpose. But what indicators are to be used to measure something so necessary? In this article, the types of air conditioning and GWP (Global Warming Potential) levels of equipment in the project phase were discussed, the issue of TEWI (Total Equivalent Warming Impact) that measures the direct and indirect environmental impacts of refrigeration equipment and air conditioning and a new methodology for the indicator was developed, the TEWI DC (DC is the direct application for Data Center), and using the formulas of this new adapted indicator it was demonstrated that the TEWI DC for Chicago (USA) was 2,784,102,640 kg CO2/10 years and Curitiba (Brazil) is 1,252,409,640 kg CO2/10 years. This difference in value corresponds to 222.30% higher annual emissions in Chicago than in Curitiba, showing that it is much more advantageous to install a Data Center in Curitiba than in Chicago in terms of environmental impact. The TEWI indicator provides a more holistic view, helping to combine energy and emissions into the same indicator.
- New HVAC Sustainability Index - TWI (Total Water Impact)Publication . Santos, Alexandre Fernandes; Gaspar, Pedro Dinis; Souza, HeraldoSales of air conditioning are growing rapidly in buildings, more than tripling between 1990 and 2016. This energy use for air conditioning comes from a combination of rising temperatures, rising population and economic growth. Energy demand for climate control will triple by 2050, consuming more energy than that currently consumed altogether by the United States, the European Union and Japan. This increase in energy will directly impact water consumption, either to directly cool a condenser of an equipment or to serve indirectly as a basis for energy sources such as hydroelectric power that feed these heating, ventilation and air conditioning (HVAC) systems. Knowing the unique and growing importance of water, a new index, Total Water Impact (TWI) is presented, which allows a holistic comparison of the impact of water use on water, air and evaporative condensation climate systems. 200 and 500 TON (tons of refrigeration) air-cooled and water-cooled systems are theoretically compared to evaluate the general water consumption level. The TWI index is higher in the smallest water condensing system. That is, holistically, water consumption is higher in the water condensing system than in the air condensing system. Thus, this index provides a new insight about energy consumption and ultimately, about sustainability.
- Best Practices on HVAC Design to Minimize the Risk of COVID-19 Infection within Indoor EnvironmentsPublication . Santos, Alexandre Fernandes; Gaspar, Pedro Dinis; Hamandosh, Aseel; Aguiar, Eliandro; Filho, António Carlos Guerra; Souza, HeraldoThe spread of Coronavirus is causing in the society all around the world a considerable degree of fear, worry and concern and particularly among healthcare workers that are at increased risk for infection. This paper gathers the strategy/guidelines to reduce the contamination in Intensive care unit (ICU) and in all the hospital environment. The ASHRAE and REHVA guidelines applied the UV-C Lamps, Pressure control filtration, Restroom actions and Humidity control to reduce the coronavirus disease (Covid-19) in ICU. The role of infection control in the design of hospitals is increasing every day. This paper highlights the role of heating, ventilating and air-conditioning minimizing the risk of infection from airborne transmission within the built environment through the application of best practices.
- New Data Center Performance Index: Perfect Design Data Center - PDDPublication . Santos, Alexandre Fernandes; Gaspar, Pedro Dinis; Souza, HeraldoData Centers (DC) are specific buildings that require large infrastructures to store all the information needed by companies. All data transmitted over the network is stored on CDs. By the end of 2020, Data Centers will grow 53% worldwide. There are methodologies that measure the e ciency of energy consumption. The most used metric is the Power Usage E ectiveness (PUE) index, but it does not fully reflect e ciency. Three DC’s located at the cities of Curitiba, Londrina and Iguaçu Falls (Brazil) with close PUE values, are evaluated in this article using the Energy Usage E ectiveness Design (EUED) index as an alternative to the current method. EUED uses energy as a comparative element in the design phase. Infrastructure consumption is the sum of energy with Heating, Ventilating and Air conditioning (HVAC) equipment, equipment, lighting and others. The EUED values obtained were 1.245 (kWh/yr)/(kWh/yr), 1.313 (kWh/yr)/(kWh/yr) and 1.316 (kWh/yr)/(kWh/yr) to Curitiba, Londrina and Iguaçu Falls, respectively. The di erence between the EUED and the PUE Constant External Air Temperature (COA) is 16.87% for Curitiba, 13.33% for Londrina and 13.30% for Iguaçu Falls. The new Perfect Design Data center (PDD) index prioritizes e ciency in increasing order is an easy index to interpret. It is a redefinition of EUED, given by a linear equation, which provides an approximate result and uses a classification table. It is a decision support index for the location of a Data Center in the project phase.
- Avaliação do desempenho térmico e energético de como são avaliados e determinados em um datacenterePublication . Santos, Alexandre Fernandes; Gaspar, Pedro Dinis; Souza, HeraldoA taxa de consumo energético associado aos datacenters tem sido aumentado significativamente na última década, sendo previsto um aumento de até 53% em 2020. A eficiência energética deste tipo de recintos de alto consumo de energia é fundamental. Já existem metodologias para mensurar essa eficiência como sejam o PUE (Power Usage Effectiveness). Todavia, este índice, apesar de importante, não reflete de forma integral a eficiência. Este estudo avalia e demonstra esta condição para 02 Datacenters com PUE muito próximos. Para tal, é comparada a eficiência com um novo índice a ser criado, o EUE (Energy Usage Effectiveness). Na métrica, ao invés de considerar a potência como elemento de comparação, faz uso da energia como fator de comparação. O estudo utiliza o aproveitamento de entalpia com uma nova metodologia para obter os resultados, tendo sido obtida uma diferença entre os índices de 4,45% em re-lação a Manaus e 17,51% em relação a cidade de Foz de Iguaçu.
- Análise de temperaturas geotérmicas para aplicação de bombas de calor no ParanáPublication . Santos, Alexandre F.; Souza, Heraldo; Cantão, Mauricio P.; Gaspar, Pedro DinisBombas de calor geotérmicas são muito utilizadas em países desenvolvidos, porém, são pouco utilizadas no Brasil, em parte porque faltam medidas de temperatura do solo brasileiro. Os objetivos deste trabalho são: apresentar medidas de temperatura geotérmica e comparar o desempenho do sistema geotérmico e do sistema convencional de ar condicionado. Apresentam-se resultados da medição de temperatura geotérmica em dez cidades paranaenses, representativas dos diferentes solos e climas. As medições foram realizadas ao longo de um ano, com equipamentos aferidos e sistemas digitais de aquisição de dados nas diferentes estações de medição instaladas. Os dados de temperatura geotérmica e ambiente foram utilizados para simulação do coeficiente de performance (COP), por meio de software de dimensionamento de sistemas em ciclo de refrigeração por compressão de vapor, baseado no diagrama de pressão-entalpia do fluido de rabalho. Verificou-se que a temperatura geotérmica medida entre janeiro e outubro de 2013 variou de 16 a 24 °C, enquanto a temperatura ambiente variou entre 2 e 35 °C. Valores médios de COP para o sistema convencional foram de 3,7 (refrigeração) e 5,0 kW/kW (aquecimento), correspondente a 5,9 e 7,9 para o sistema BCG, o que significa ganho em eficiência de 59% com o uso do sistema geotérmico.
- Refrigeration of COVID-19 Vaccines: Ideal Storage Characteristics, Energy Efficiency and Environmental Impacts of Various Vaccine OptionsPublication . Santos, Alexandre Fernandes; Gaspar, Pedro Dinis; Souza, Heraldo J. L. deThis article considers the ideal storage conditions for multiple vaccine brands, such as Pfizer, Moderna, CoronaVac, Oxford–AstraZeneca, Janssen COVID-19 and Sputnik V. Refrigerant fluid options for each storage condition, thermal load to cool each type of vaccine and environmental impacts of refrigerants are compared. An energy simulation using the EUED (energy usage effectiveness design) index was developed. The Oxford–AstraZeneca, Janssen COVID-19 and CoronaVac vaccines show 9.34-times higher energy efficiency than Pfizer. In addition, a TEWI (total equivalent warming impact) simulation was developed that prioritizes direct environmental impacts and indirect in refrigeration. From this analysis, it is concluded that the cold storage of Oxford–AstraZeneca, Janssen COVID-19 and CoronaVac vaccines in Brazil generates 35-times less environmental impact than the Pfizer vaccine.
- Avaliação do desempenho térmico e energético de um datacenter por um novo índice de eficiênciaPublication . Santos, Alexandre Fernandes; Gaspar, Pedro Dinis; Souza, HeraldoOs datacenters têm um crescimento até 2020 de 53%. Existem metodologias que mensura m essa eficiência com o PUE (Power Usage Effectiveness) índice importante, não reflete de forma integral a eficiência. 03 DC’s com PUE próximos como alternativa ao método atual este trabalho descreve o EUED (Energy Usage Effectiveness Design), usa energia como elemento comparativo na fase projeto, usando entalpia como novo método para obter resultados. Os consumos com infraestrutura é a somatório da energia com equipamentos de HVAC, equipamentos, iluminação e outros. Usando o EUED, foram 1,245kW/kW para Curitiba, 1,260 kW/kW para São Paulo e de 1,377 kW/kW para Rio de Janeiro. A diferença de 16,86% para Curitiba, de 16,19% São Paulo e 10,31% Rio de Janeiro em relação ao PUE COA (Power Usage Effectiveness Constant Outdoor Air). TEWI é uma métrica do impacto do aquecimento global, com base nas emissões de gases efeito estufa. Verificou que mesmo com o consumo HVAC anual kWh semelhantes, 2 cidades diferentes, com TEWI de Chicago (EUA) é 1,781,566,043 CO2 kW/10 anos e Curitiba (BRASIL) é 667,042, 128 CO2 kW/10 anos. Corresponde a uma emissão anual maior que a de Curitiba, de 267,08%.
- Evaluation of the Thermal Performance and Energy Efficiency of CRAC Equipment through Mathematical Modeling Using a New Index COP WEUEDPublication . Santos, Alexandre F.; Gaspar, Pedro Dinis; Souza, Heraldo J. L. deAs the world data traffic increasingly grows, the need for computer room air conditioning (CRAC)-type equipment grows proportionally. The air conditioning equipment is responsible for approximately 38% of the energy consumption of data centers. The energy efficiency of these pieces of equipment is compared according to the Energy Standard ASHRAE 90.1-2019, using the index Net Sensible Coefficient Of Performance (NetSCOP). This method benefits fixed-speed compressor equipment with a constant inlet temperature air-cooled condenser (35 C). A new method, COP WEUED (COP–world energy usage effectiveness design), is proposed based on the IPLV (integrated part load value) methodology. The IPLV is an index focused on partial thermal loads and outdoor temperature data variation for air intake in the condenser. It is based on the average temperatures of the USA’s 29 major cities. The new method is based on the 29 largest cities worldwide and with datacenter- specific indoor temperature conditions. For the same inverter compressor, efficiencies of 4.03 and 4.92 kW/kW were obtained, using ASHRAE 90.1-2019 and the proposed method, respectively. This difference of almost 20% between methods is justified because, during less than 5% of the annual hours, the inlet air temperature in the condenser is close to the NetSCOP indication.