Richmond City Hall in B.C. pumps twice as much fresh air into occupied zones than is required by the standard, and yet achieves substantial energy savings.
The first concern was air quality. Stantec and the design team specified a four-pipe fan coil system for heating, cooling and ventilation. The system is designed to supply to the occupied areas almost double the amount of outside air that is prescribed by ASHRAE 62-99. The system improves the indoor air quality and allows the HVAC system to operate in a compartmental configuration, thus promoting better thermal zoning so that heating and cooling respond to space demand. Only the areas of the building requiring 24-hour air conditioning, such as the computer rooms, are served from independent HVAC systems.
The building ventilation air is provided by two central make-up air handling units located in the penthouse mechanical room. The unit serving the low-rise areas has variable air volume control (VAV) to provide demand ventilation to the multi-purpose meeting rooms. The use of duct liner was minimized to reduce the potential contamination of the ventilation air.
The second concern was that the building would operate at a lower than normal energy level. The building was modeled using the U.S. Department of Energy (DOE) hourly computer program to optimize the building siting, envelope, lighting and HVAC systems. The general results of the simulations indicated the city hall would consume 26.4% less energy compared to a building designed to meet the requirements of Canada's Model Energy Code for Buildings (MNECB). This result was achieved even with the higher than normal ventilation rates. The total energy consumption of the installed design is 79,600 Gigajoules, and the estimated yearly savings are $32,700. The building also qualified for a rebate of $65,350 from NRCan's Commercial Buildings Incentive Program.
DOE--Department of Energy "The Department of Energy's overarching mission is enhancing national security. Responsibility for accomplishing this mission is shared between four principal program lines."