We implement energy saving measures that made possible building energy usage of 20%-50% less than a code baseline building. These techniques have been carefully engineered to allow the entire building and occupants to function together in a cohesive, comfortable, and sustainable manner. Some of the mechanical system techniques we have used for this project include:
- Use of variable speed drives on system motors to reduce energy use at a low load conditions.
- Use of solid state speed controls on small fans and two speed motors to allow reduced operation when peak performance is not required.
- Use of C02 sensors to reduce the outside air quantity to match actual space needs, saving energy to heat and cool the air.
- Use of night purge cycles to allow cool evening air (or early morning) air to pre-cool the building mass.
- Oversized economizer systems to allow outside air for cooling (in addition to natural ventilation) at higher outdoor air temperatures.
- Higher temperature difference on heating and cooling hydronic systems to reduce the quantity of pumped water, saving energy and initial costs for distribution systems and equipment.
- Use of two-way control valves which shut-off system flows and allow pump variable speed drives to throttle back system pumps and reduce energy usage.
- Use of transferred air for make-up air to exhausted areas saving on equipment use and having to heat or cool large quantities of outside
- Correct sizing of equipment and equipment motors for peak efficiency (i.e. not oversized).
- Inter-tie of space occupancy sensors to HVAC equipment to reduce outside air to space when they are not occupied.
- High efficiency chillers and boilers.
- High efficiency motors with power factor correction capacitors
- Control schemes that include optimum start/stop, reset of system supply temperatures, proportional-integral control.
- Use of radiant heat to allow lower indoor air temperatures and reduced heat loss/gain.
- Reduce (or eliminate) cooling and coordinate use with natural ventilation systems.
- Document expected energy performances and compare with actual on an on-going basis to ensure proper operation at building occupancy, and continued efficient performance throughout the life of the building.