Mechanical ventilation in buildings requires appropriate systems for heating and cooling. The costs of energy demand represent a high percentage of the global costs for climatisation. As a part of a project concerning these subjects the development of a computer code for evaluating energy load due to mechanical ventilation in buildings is in progress. The mathematical model is based on simplified equations to fit dynamically the psychometric curves. Inlet air flow rates are evaluated according to the more recent Italian regulations.
Providing people with a quality indoor environment means full air conditioning with an energy use tag that we would rather not mention in the debate about environmental impact and sustainability. But is this really the case? Is it not possible to design mechanical systems so they use less energy than their naturally ventilated counterparts? The law of conservation of energy means we can use the same energy repeatedly. As long as we are aware of how energy is degraded in quality and temperature terms, we can design systems that repeatedly recover and reuse energy.
Mechanical ventilation systems, designed to meet ASHRAE's Standard 62-1989 and to modify building pressures, were installed in two New Mexico elementary schools to reduce elevated levels of indoor radon, carbon dioxide, and airborne particles. Although the systems did not meet design conditions for outdoor air delivery, ventilation rates were increased by factors of 2 to 4 over pre-existing natural ventilation rates, and levels of indoor air pollutants were significantly reduced.