• Working - Office ventilation
• EBV - Building Ventilation

Energy consumption for heating and heat recovery

Energy consumption for heating is affected by many different factors:

• Heat recovery method - cross-flow (VEX100) or rotary (VEX200)
• Principal means of control (CAV, VAV, DCV)
• Temperature duration curve
• The chosen supply- and extract air temperatures

The calculations in the diagrams above are made in EXselect under the following conditions:

CAV (Constant Air Volume):

• Reference year for UK (outdoor temperature)
• Office surroundings with 5 workdays a week
• 10 hours Comfort operating time/workday (max. air volume - optimal indoor climate)
• 10 hours Standby operating time/workday (reduced air volume - energy saving)
• Extract air temperature 22°C
• Air supply temperature 20°C

VAV (Variable Air Volume):

• Like the CAV - but only 6 hours of Comfort operating time, since it is a well-known fact that offices are only used 60% of the time
• The rest of the time (18 hours) as Standby operating time

DCV (Demand Controlled Ventilation):

• Like the VAV - but only 75% load during 60% of the worktime