Office - Single-zone commercial office building with rooftop package unit
Synopsis
class office { double floor_area[sf]; double floor_height[ft]; double exterior_ua[Btu/degF/h]; double interior_ua[Btu/degF/h]; double interior_mass[Btu/degF]; double glazing[sf]; double glazing.north[sf]; double glazing.northeast[sf]; double glazing.east[sf]; double glazing.southeast[sf]; double glazing.south[sf]; double glazing.southwest[sf]; double glazing.west[sf]; double glazing.northwest[sf]; double glazing.horizontal[sf]; double glazing.coefficient[pu]; double occupancy; double occupants; char256 schedule; double air_temperature[degF]; double mass_temperature[degF]; double temperature_change[degF/h]; double outdoor_temperature[degF]; double Qh[Btu/h]; double Qs[Btu/h]; double Qi[Btu/h]; double Qz[Btu/h]; enumeration {OFF=0, VENT=5, ECON=4, COOL=3, AUX=2, HEAT=1} hvac_mode; double hvac.cooling.balance_temperature[degF]; double hvac.cooling.capacity[Btu/h]; double hvac.cooling.capacity_perF[Btu/degF/h]; double hvac.cooling.design_temperature[degF]; double hvac.cooling.efficiency[pu]; double hvac.cooling.cop[pu]; double hvac.heating.balance_temperature[degF]; double hvac.heating.capacity[Btu/h]; double hvac.heating.capacity_perF[Btu/degF/h]; double hvac.heating.design_temperature[degF]; double hvac.heating.efficiency[pu]; double hvac.heating.cop[pu]; double lights.capacity[kW]; double lights.fraction[pu]; double plugs.capacity[kW]; double plugs.fraction[pu]; complex demand[kW]; complex total_load[kW]; complex energy[kWh]; double power_factor; complex power[kW]; complex current[A]; complex admittance[1/Ohm]; complex hvac.demand[kW]; complex hvac.load[kW]; complex hvac.energy[kWh]; double hvac.power_factor; complex lights.demand[kW]; complex lights.load[kW]; complex lights.energy[kWh]; double lights.power_factor; double lights.heatgain_fraction; double lights.heatgain[[[Units|kW]; complex plugs.demand[[[Units|kW]; complex plugs.load[[[Units|kW]; complex plugs.energy[[[Units|kWh]; double plugs.power_factor; double plugs.heatgain_fraction; double plugs.heatgain[kW]; double cooling_setpoint[degF]; double heating_setpoint[degF]; double thermostat_deadband[degF]; double control.ventilation_fraction; double control.lighting_fraction; double ACH; }
Properties
Property name | Type | Unit | Description |
---|---|---|---|
floor_area | double | ft^2 | Floor area of the office (presuming one floor). |
floor_height | double | ft | Ceiling height within the office interior |
exterior_ua | double | BTU/degF/hr | Exterior thermal resistance |
interior_ua | double | BTU/degF/hr | Interior thermal resistance |
interior_mass | double | BTU/degF | The thermal mass of the interior finishing and building materials |
glazing | double | ft^2 | The external glazing area (total area) |
glazing.north | double | ft^2 | The external glazing area facing north |
glazing.northeast | double | ft^2 | The external glazing area facing north-east |
glazing.east | double | ft^2 | The external glazing area facing east |
glazing.southeast | double | ft^2 | The external glazing area facing south-east |
glazing.south | double | ft^2 | The external glazing area facing south |
glazing.southwest | double | ft^2 | The external glazing area facing south-west |
glazing.west | double | ft^2 | The external glazing area facing west |
glazing.northwest | double | ft^2 | The external glazing area facing north-west |
glazing.horizontal | double | ft^2 | The external glazing area facing up (skyward) |
glazing.coefficient | double | per unit | The fraction of solar radiation that is transmitted by the glazing. |
occupancy | double | - | Current occupancy ratio |
occupants | double | people | Total occupants for the office |
schedule | char256 | - | Schedule string. Semicolon delimited cron-style schedule definition. |
air_temperature | double | degF | Office interior air temperature |
mass_temperature | double | degF | Office interior mass temperature |
temperature_change | double | degF/hr | The rate of change of temperature since the last update |
Qh | double | BTU/hr | The HVAC gain/loss since the last update |
Qs | double | BTU/hr | The solar heat gain since the last update |
Qi | double | BTU/hr | The internal heat gains since the last update |
Qz | double | BTU/hr | The inter-zonal heat gain/loss since the last update |
hvac_mode | enumeration | - | Current mode of the HVAC system. HEAT, AUX, COOL, ECON, VENT, or OFF. |
hvac.cooling.balance_temperature | double | degF | The balance temperature of the HVAC cooler |
hvac.cooling.capacity | double | BTU/hr | The constant heat output capacity of the HVAC cooler (should be negative) |
hvac.cooling.capacity_perF | double | BTU/degF/hr | The temperature-dependent heat output capacity of the HVAC cooler (should be negative) |
hvac.cooling.design_temperature | double | degF | The design temperature of the HVAC cooler |
hvac.cooling.efficiency | double | - | The cooling efficiency of the HVAC cooler |
hvac.cooling.cop | double | - | Coefficient of performance of the HVAC cooler |
hvac.heating.balance_temperature | double | degF | The balance temperature of the HVAC heater |
hvac.heating.capacity | double | BTU/hr | The constant heat output capacity of the HVAC heater |
hvac.heating.capacity_perF | double | BTU/degF/hr | The temperature-dependent heat output capacity of the HVAC heater |
hvac.heating.design_temperature | double | degF | The design temperature of the HVAC heater |
hvac.heating.efficiency | double | BTU/W | The heating efficiency of the HVAC heater |
hvac.heating.cop | double | - | Coefficient of performance of the HVAC heater |
lights.capacity | double | kW | Total power of the lights installed in the office |
lights.fraction | double | pu | The fraction of the installed lights that are turned on |
plugs.capacity | double | kW | Total power of the devices plugged into wall sockets |
plugs.fraction | double | pu | The current fraction of the total power draw from the various devices |
demand | complex | kW | Aggregate peak power draw from the office |
total_load | complex | kW | Current aggregate power draw from the office |
energy | complex | kWh | Accumulated energy consumed by the office |
power_factor | complex | - | The power factor of the house load |
power | complex | kW | Constant power component of the office load |
current | complex | A | Constant current component of the office load |
admittance | complex | 1/Ohm | Constant resistance component of the office load |
hvac.demand[kW] | complex | kW | The HVAC load |
hvac.load[kW] | complex | kW | The HVAC load |
hvac.energy | double | kWh | The HVAC energy use |
hvac.power_factor | complex | - | The HVAC power factor |
lights.demand[kW] | complex | kW | The lighting load |
lights.load | complex | kW | The lighting load |
lights.energy | complex | kWh | The lighting energy use |
lights.power_factor | double | - | The lighting power factor |
plugs.demand | complex | kW | The plug load |
plugs.load | complex | kW | The plug load |
plugs.energy | complex | kWh | The plug energy use |
plugs.power_factor | double | - | The plug power factor |
cooling_setpoint | double | degF | The cooling thermostat set-point |
heating_setpoint | double | degF | The heating thermostat set-point |
thermostat_deadband" | double | degF | The thermostat deadband (hysteresis) |
control.ventilation_fraction | double | pu | The current outside air fraction for ventilation |
control.lighting_fraction | double | pu | The current lighting fraction in effect |
Default Office
The "default office" is an undefined construct. The minimum definition for an office object must include
object office{ floor_height 6 ft; floor_area 4000 sf; interior_mass 2000; interior_UA 2.0; exterior_UA 2.0; hvac.cooling.capacity -4500; // must be negative hvac.heating.capacity 4500; }
Office Schedules
The office has a built-in occupancy schedule subsystem that is used to determine the minimum air change coefficient. This subsystem parses a string and constructs a bitfield for the hours of each day that the building should be occupied. By default, office buildings are occupied from 8am to 5pm local time, Monday through Friday.
The format for the office schedule consists of two parts, the day and the hours, in a semicolon delimited list. The default string is "1-5 8-17". The first part is the range for the days of the week, with 0 being Sunday, 1 for Monday, etc. The hours are numbered 0-23 and reflect a 24 hour clock. Multiple schedule elements can be aggregated with an OR operation by separating them with semicolons. For example, "1-4 8-17; 5 8-20; 6 8-23; 0 8-20" would define an 8-5 schedule Mon-Thur, 8-8 on Friday, 8am-11pm on Saturday, and 8-8 on Sunday.
Example
TODO:
Bugs
As of Navajo (Version 4.3) the office building class has not been validated. Use of the residential house class is recommended with appropriate adjustments to parameters until validation is completed.
See also
- User's manuals
- Commercial module
- Building types
- Office
- Large office TODO:
- Small office TODO:
- Retail TODO:
- Grocery TODO:
- Food_service TODO:
- Lodging TODO:
- School TODO:
- Health TODO:
- Technical documents
- Residential
- Modules