From GridLAB-D Wiki
Jump to: navigation, search

house - implements a single family home


class house {
	parent residential_enduse;
	function attach_enduse();
	object weather; 
	double floor_area[sf];
	double gross_wall_area[sf]; 
	double ceiling_height[ft];
	double aspect_ratio;
	double envelope_UA[Btu/degF];
	double window_wall_ratio;
	double number_of_doors; 
	double exterior_wall_fraction;
	double interior_exterior_wall_ratio;
	double exterior_ceiling_fraction;
	double exterior_floor_fraction; 
	double window_shading;
	double window_exterior_transmission_coefficient;
	double solar_heatgain_factor; 
	double airchange_per_hour; 
	double airchange_UA[Btu/degF]; 
        double UA;
	double internal_gain[Btu/h]; 
	double solar_gain[Btu/h]; 
	double incident_solar_radiation[Btu/h]; 
	double heat_cool_gain[Btu/h]; 
        set {NONE=0,H=1,N=2,E=3,S=4,W=5} include_solar_quadrant;
        enumeration {DEFAULT=0,FLAT=1,LINEAR=2,CURVED=3} heating_cop_curve;
	double thermostat_deadband[degF]; 
	int16 thermostat_cycle_time; 
	timestamp thermostat_last_cycle_time; 
	double heating_setpoint[degF]; 
	double cooling_setpoint[degF]; 
	double design_heating_setpoint[degF]; 
	double design_cooling_setpoint[degF]; 
	double over_sizing_factor; 
	double design_heating_capacity[Btu/h]; 
	double design_cooling_capacity[Btu/h]; 
	double cooling_design_temperature[degF]; 
	double heating_design_temperature[degF]; 
	double design_peak_solar[Btu/h]; 
	double design_internal_gains[Btu/h]; 
	double air_heat_fraction[pu]; 
	double mass_solar_gain_fraction[pu]; 
	double mass_internal_gain_fraction[pu]; 
	double auxiliary_heat_capacity[Btu/h]; 
	double aux_heat_deadband[degF]; 
	double aux_heat_temperature_lockout[degF]; 
	double aux_heat_time_delay[s]; 
	double cooling_supply_air_temp[degF]; 
	double heating_supply_air_temp[degF]; 
	double duct_pressure_drop[inh2o]; 
	double fan_design_power[W]; 
	double fan_low_power_fraction[pu]; 
	double fan_power[kW]; 
	double fan_design_airflow[cfm]; 
	double fan_impedance_fraction[pu]; 
	double fan_power_fraction[pu]; 
	double fan_current_fraction[pu]; 
	double fan_power_factor[pu]; 
	double heating_demand; 
	double cooling_demand; 
	double heating_COP[pu]; 
	double cooling_COP[Btu/kWh]; 
	double air_temperature[degF]; 
	double outdoor_temperature[degF]; 
	double outdoor_rh[%]; 
	double mass_heat_capacity[Btu/degF]; 
	double mass_heat_coeff[Btu/degF]; 
	double mass_temperature[degF]; 
	double air_volume[cf]; 
	double air_mass[lb]; 
	double air_heat_capacity[Btu/degF]; 
	double latent_load_fraction[pu]; 
	double total_thermal_mass_per_floor_area[Btu/degF];
	double interior_surface_heat_transfer_coeff[Btu/h];
	double number_of_stories; 
	double is_AUX_on; 
	double is_HEAT_on; 
	double is_COOL_on; 
	double thermal_storage_present; 
	double thermal_storage_in_use; 
	set {LOCKOUT=4, TIMER=2, DEADBAND=1, NONE=0} auxiliary_strategy; 
	enumeration {AUX=3, COOL=4, OFF=1, HEAT=2, UNKNOWN=0} system_mode; 
	enumeration {AUX=3, COOL=4, OFF=1, HEAT=2, UNKNOWN=0} last_system_mode; 
	enumeration {RESISTANCE=4, HEAT_PUMP=3, GAS=2, NONE=1} heating_system_type;
	enumeration {HEAT_PUMP=2, ELECTRIC=2, NONE=1} cooling_system_type;
	enumeration {ELECTRIC=2, NONE=1} auxiliary_system_type;
	enumeration {TWO_SPEED=3, ONE_SPEED=2, NONE=1} fan_type;
	enumeration {UNKNOWN=7, VERY_GOOD=6, GOOD=5, ABOVE_NORMAL=4, NORMAL=3, BELOW_NORMAL=2, LITTLE=1, VERY_LITTLE=0} thermal_integrity_level; 
	enumeration {LOW_E_GLASS=2, GLASS=1, OTHER=0} glass_type; 
	enumeration {INSULATED=4, WOOD=3, THERMAL_BREAK=2, ALUMINIUM=1, ALUMINUM=1, NONE=0} window_frame; 
	enumeration {HIGH_S=5, LOW_S=4, REFL=3, ABS=2, CLEAR=1, OTHER=0} glazing_treatment; 
	enumeration {OTHER=4, THREE=3, TWO=2, ONE=1} glazing_layers; 
	enumeration {FULL=2, BASIC=1, NONE=0} motor_model; 
	enumeration {VERY_GOOD=4, |GOOD=3, AVERAGE=2, POOR=1, VERY_POOR=0} motor_efficiency; 
	int64 last_mode_timer;
	double hvac_motor_efficiency[unit]; 
	double hvac_motor_loss_power_factor[unit]; 
	double Rroof[Btu/degF.h]; 
	double Rwall[Btu/degF.h]; 
	double Rfloor[Btu/degF.h]; 
	double Rwindows[Btu/degF.h]; 
	double Rdoors[Btu/degF.h]; 
	double hvac_breaker_rating[A]; 
	double hvac_power_factor[unit]; 
	double hvac_load; 
	double last_heating_load; 
	double last_cooling_load; 
	complex hvac_power; 
	double total_load; 
	enduse panel; 
	double design_internal_gain_density[W/sf]; 
	bool compressor_on;
	int64 compressor_count;
	timestamp hvac_last_on;
	timestamp hvac_last_off;
	double hvac_period_length;
	double hvac_duty_cycle;
	enumeration {NONE=2, BAND=1, FULL=0} thermostat_control; 


Physical Design

Property name Type Unit Description
floor_area double sf Home conditioned floor area
gross_wall_area double sf Gross outdoor wall area
ceiling_height double ft Average ceiling height
aspect_ratio double none Aspect ratio of the home's footprint
window_wall_ratio double none Ratio of window area to wall area
number_of_doors double none Ratio of door area to wall area
exterior_wall_fraction double none Ratio of exterior wall ratio to wall area
interior_exterior_wall_ratio double none Ratio of interior to exterior walls
exterior_ceiling_fraction double none Ratio of external ceiling sf to floor area
exterior_floor_fraction double none Ratio of floor area used in UA calculation
number_of_stories double none Number of stories within the structure
Rroof double degF.sf.h/Btu Roof R-value
Rwall double degF.sf.h/Btu Wall R-value
Rfloor double degF.sf.h/Btu Floor R-value
Rwindows double degF.sf.h/Btu Window R-value
Rdoors double degF.sf.h/Btu Door R-value
window_shading double none Transmission coefficient through window due to glazing
window_exterior_transmission_coefficient double none Coefficient for the amount of energy that passes through window

HVAC Design

Property name Type Unit Description
cooling_design_temperature double degF System cooling design temperature
heating_design_temperature double degF System heating design temperature
design_peak_solar double Btu/h System design solar load
design_internal_gains double Btu/h System design internal gains
cooling_supply_air_temp double degF Temperature of air blown out of the cooling system
heating_supply_air_temp double degF Temperature of air blown out of the heating system
duct_pressure_drop double in End-to-end pressure drop for the ventilation ducts (inches of water)
heating_COP double pu System heating performance coefficient
cooling_COP double Btu/kWh System cooling performance coefficient
design_heating_capacity double Btu/h System heating capacity
design_cooling_capacity double Btu/h System cooling capacity
design_heating_setpoint double degF System design heating setpoint
design_cooling_setpoint double degF System design cooling setpoint
auxiliary_heat_capacity double Btu/h Installed auxiliary heating capacity
over_sizing_factor double unit Over sizes the heating and cooling system from standard specifications (0.2 = 120% sizing)


Property name Type Unit Description
solar_heatgain_factor double none Product of the window area, window transmitivity, and the window exterior transmission coefficient
airchange_per_hour double none Number of air-changes per hour
internal_gain double Btu/h Internal heat gains
solar_gain double Btu/h Solar heat gains
incident_solar_radiation double Btu/h.sf Average incident solar radiation hitting the house
heat_cool_gain double Btu/h System heat gains(losses)
air_heat_fraction double pu Fraction of the heat gain/loss that goes to air (as opposed to mass)
mass_heat_capacity double Btu/degF Interior mass heat capacity
mass_heat_coeff double Btu/degF.h Interior mass heat exchange coefficient
air_heat_capacity double Btu/degF Air thermal mass
total_thermal_mass_per_floor_area double Btu/degF.sf Total thermal mass per floor area
interior_surface_heat_transfer_coeff double Btu/h.degF.sf Interior surface heat transfer coefficient
design_internal_gain_density double W/sf Average density of heat generating devices in the house

Fan Design

Property name Type Unit Description
fan_design_power double W Designed maximum pwer draw of the ventilation fan
fan_low_power_fraction double pu Fraction of ventilation fan power draw during low-power mode (two-speed only)
fan_power double kW Current ventilation fan power draw
fan_design_airflow double cfm Designed airflow for the ventilation system
fan_impedance_fraction double pu Impedance component of fan ZIP load
fan_power_fraction double pu Power component of fan ZIP load
fan_current_fraction double pu Current component of fan ZIP load
fan_power_factor double pu Power factor of the fan load
hvac_motor_efficiency double unit Percent efficiency of HVAC motor when using motor model
hvac_motor_loss_power_factor double unit Power factor of motor loasses when using motor model


Property name Type Unit Description
heating_setpoint double degF Thermostat heating setpoint
cooling_setpoint double degF Thermostat cooling setpoint
aux_heat_deadband double degF Temperature offset from standard heat activation to auxiliary heat activation
aux_heat_temperature_lockout double degF Temperature at which auxiliary heat will not engage above
aux_heat_time_delay double s Time required for heater to run until auxiliary heating engages
thermostat_deadband double degF Deadband of thermostat control
thermostat_cycle_time int16 none Mimimum time in seconds between thermostat updates
thermostat_last_cycle_time timestamp none Last time the thermostat changed state
last_mode_timer int64 none


Property name Type Unit Description
air_temperature double degF Indoor air temperature
outdoor_temperature double degF Outdoor air temperature
mass_temperature double degF Interior mass temperature
air_volume double cf Air volume
air_mass double lb Air mass
latent_load_fraction double pu Fractional increase in cooling load due to latent heat
heating_demand double none The current power draw to run the heating system
cooling_demand double none The current power draw to run the cooling system
envelope_UA double Btu/degF.h Overall UA of the home's envelope
airchange_UA double Btu/degF.h Additional UA due to air infiltration


Property name Type Unit Description
panel enduse none Total panel enduse load
hvac_breaker_rating double A Determines the amount of curren the HVAC circuit breaker can handle
hvac_power_factor double unit Power factor of HVAC
hvac_load double none Heating/cooling system load
total_load double none Total load


Property name Type Unit Description
system_type set none Describe HVAC system of house. (GAS, AIRCONDITIONING, FORCEDAIR, TWOSTAGE, RESISTIVE)
heating_system_type enumeration none Set heating mechanism for house (RESISTANCE, HEAT_PUMP, GAS, NONE)
cooling_system_type enumeration none Set cooling mechanism for hosue (HEAT_PUMP, ELECTRIC, NONE)
auxiliary_system_type enumeration none Can be specified for HEAT_PUMP heating systems (ELECTRIC, NONE)
auxiliary_strategy set none Control strategy for auxiliary heat (LOCKOUT, TIMER, DEADBAND, NONE)
system_mode enumeration none Heating/cooling system operation state (UNKNOWN, HEAT, OFF, COOL, AUX)
fan_type enumeration none Circulation fan (TWO_SPEED, ONE_SPEED, NONE)
thermal_integrity_level enumeration none Default envelope UA settings (VERY_GOOD, GOOD, ABOVE_NORMAL, NORMAL, BELOW_NORMAL, LITTLE, VERY_LITTLE, UNKNOWN)
glass_type enumeration none Type of window glass used (LOW_E_GLASS, GLASS, OTHER)
window_frame enumeration none Type of window frame (INSULATED, WOOD, THERMAL_BREAK, ALUMINUM, NONE)
glazing_treatment enumeration none Treatment that increases the reflectivity of exterior windows (HIGH_S, LOW_S, REFL, ABS, CLEAR, OTHER)
glazing_layers enumeration none Number of layers of glass in each window (THREE, TWO, ONE, OTHER)
motor_model enumeration none Indicates the level of detail used in modeling the HVAC motor parameters (FULL, BASIC, NONE)
motor_efficiency enumeration none Describes efficiency of the motor when using a motor model (VERY_GOOD, GOOD, AVERAGE, POOR, VERY_POOR)

Default House

The default house does not require any parameters be set. Thus, the minimum allowed specification for a single family house is

house {

New houses are created with the following default values (meaning if the value is not set in the GLM file, it will be calculated automatically).

Default parameter values
Parameter Default value
load.power_fraction 0.8
load.impedance_fraction 0.2
load.current_fraction 0.0
design_internal_gain_density 0.6 W/sf
thermal_integrity_level UNKNOWN
hvac_breaker_rating 0.0 A
hvac_power_factor 0.0
Tmaterials 0.0 degF
cooling_supply_air_temp 50.0 degF
heating_supply_air_temp 150.0 degF
heating_system_type HEAT_PUMP
cooling_system_type UNKNOWN
auxiliary_system_type UNKNOWN
fan_type UNKNOWN
fan_power_factor 0.96
fan_current_fraction 0.7332
fan_impedance_fraction 0.2534
fan_power_fraction 0.0135
glazing_layers TWO
glass_type LOW_E_GLASS
glazing_treatment CLEAR
window_frame THERMAL_BREAK
motor_model NONE
motor_efficiency AVERAGE
hvac_motor_efficiency 1.0
hvac_motor_loss_power_factor 0.125
hvac_motor_real_loss 0.0
hvac_motor_reactive_loss 0.0
thermal_storage_present FALSE
thermal_storage_inuse FALSE

Certain parameters are calculated by default as follows

Thermal integrity levels
thermal_integrity_level Rroof Rwall Rfloor Rdoors Rwindows airchange_per_hour
VERY_LITTLE 11.0 4.0 4.0 3.0 1/1.27 1.5
LITTLE 19.0 11.0 4.0 3.0 1/0.81 1.5
BELOW_NORMAL 19.0 11.0 11.0 3.0 1/0.81 1.0
NORMAL 30.0 11.0 19.0 3.0 1/0.6 1.0
ABOVE_NORMAL 30.0 19.0 11.0 3.0 1/0.6 1.0
GOOD 30.0 19.0 22.0 5.0 1/0.47 0.5
VERY_GOOD 48.0 19.0 22.0 5.0 1/0.47 0.5

Glazing solar heat gain coefficient (glazing_shgc) by window frame type (window_frame)
glazing_treatment CLEAR ABS REFL LOW_S HIGH_S
window_frame NONE 0.86 0.76 0.68 0.73 0.62 0.34 0.31 0.29 0.34 0.41 0.27 0.70 0.62
ALUMINUM 0.75 0.67 0.60 0.64 0.55 0.31 0.28 0.27 0.31 0.37 0.25 0.62 0.55
THERMAL_BREAK 0.75 0.67 0.60 0.64 0.55 0.31 0.28 0.27 0.31 0.37 0.25 0.62 0.55
WOOD 0.64 0.57 0.51 0.54 0.46 0.26 0.24 0.22 0.26 0.31 0.21 0.52 0.46
INSULATED 0.64 0.57 0.51 0.54 0.46 0.26 0.24 0.22 0.26 0.31 0.21 0.52 0.46

Values for Rwindows.
window_frame NONE undef 1/0.30 1/0.27 1/1.04 1/0.48 1/0.31 2.0
ALUMINUM undef 1/0.67 1/0.64 1/1.27 1/0.81 1/0.67
THERMAL_BREAK undef 1/0.47 1/0.43 1/1.08 1/0.60 1/0.46
WOOD undef 1/0.41 1/0.37 1/0.90 1/0.53 1/0.40
INSULATED undef 1/0.33 1/0.31 1/0.81 1/0.44 1/0.34

Automatically calculated defaults
Parameter Default value
panel.max_amps 200 A
fan_type heating_system_type==HEAT_PUMP ? ONE_SPEED : NONE
 TODO:  Add rest of auto inits from house_e::init()


module residential;
object house {

See Also