Office Buildings

Healthier building environments provide increased health, happiness and productivity in addition to reducing employee attrition. Designing high performance small or medium sized office buildings can present a challenge when trying to deliver a superior indoor environment while meeting increasingly stringent demands for efficiency.

To that end, ASHRAE has developed an Advanced Energy Design Guide to provide practical and realistic strategies for improving the indoor environment for office buildings, with off-the-shelf technologies, that is free to download and very accessible. It is written in a “how-to” format and recommends several HVAC strategies to achieve a 50% energy savings while delivering superior indoor environmental quality.

Recommendations that are applicable to all climate zones include, but are not limited to: water source or ground source heat pump systems (WSHP/GSHP), Dedicated Outdoor Air Systems (DOAS) and exhaust air energy recovery.

It is recommended that the energy recovery device should have a minimum total effectiveness as indicated in the following table:

Total System Effectiveness with Energy Recovery
Condition
Effectiveness
Sensible Latent Total
Heating at 100% airflow 78 70 75 
Heating at 75% airflow 83 77 82 
Cooling at 100% airflow 80 71 75 
Cooling at 75% airflow 84 78 82

The energy recovery device should also not have a supply side pressure drop greater than 0.85-inch w.c. or 0.65-inch w.c. on the return; while a total energy recovery device should be used, caution should be exercised when employing an enthalpy for critical spaces.

Venmar CES Dedicated Outdoor Air Solutions® are designed with high efficiency energy recovery technologies at their core and incorporate a variety of extremely efficient options and features to meet or exceed your design objectives.

Indoor Dedicated Outdoor Air System with Ground Source Heat PumpSystems Unlimited – Iowa City, IA

Ground Source Heat Pump

  • 38,400 ft2 office building and training facility.
  • Owner concerned with energy costs and indoor air quality.
  • Solution: 8,000 cfm, 30-ton Venmar CES integrated ground source heat pump energy recovery ventilator with AHRI Certified™ total energy wheel air-to-air heat exchanger and three 5-ton ground source heat pumps supplying ceiling mounted radiant ground source heat pumps.