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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.
- 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.