Summary Outputs (KPIs)

When creating an Objective, Additional Output or Constraint it is necessary to select a Summary output (aka KPI) to define the output involved. This topic summarises the Summary outputs available for selection.

List of KPIs

You can find more detailed descriptions of many of these outputs on the Simulation Detailed Results page.

Comfort

All comfort outputs are for the whole building using an area-weighted average of discomfort calculated for each zone. Note that the comfort-related outputs are termed "discomfort" because by convention DesignBuilder aims to minimise objectives and in the context of standardising optimisation outputs it is better to minimise discomfort than to maximise comfort.

Discomfort ASHRAE 55 (sum clo) - total discomfort hours when summer clothes are worn (see comments below for Discomfort (all clo))
Discomfort ASHRAE 55 (win clo) - total discomfort hours when winter clothes are worn (see comments below for Discomfort (all clo))
Discomfort ASHRAE 55 (all clo) - total discomfort hours when winter or summer clothes are worn based on ASHRAE 55 method. Note that this objective is not the same as the building level aggregation method used by EnergyPlus in the Summary output html data which adds up hours in which any zone in the building is uncomfortable. If you would like to only consider occupied hours in your comfort analysis then make sure this option is set in the main Simulation options dialog.

Discomfort Summer ASHRAE 55 Adaptive 80% Acceptability - Reports whether the operative temperature falls into the 80% acceptability limits of the adaptive comfort in ASHRAE 55-2010 during summer occupied hours. A value of 1 means within (inclusive) the limits, i.e. the zone operative temperature is no more than 2.5°C from than the ASHRAE 55 Adaptive model temperature. A value of 0 means outside the limits (i.e. uncomfortable), and a value of -1 means not applicable, i.e. the running average outdoor air temperature is below 10°C.
Discomfort Summer ASHRAE 55 Adaptive 90% Acceptability - Reports whether the operative temperature falls into the 90% acceptability limits of the adaptive comfort in ASHRAE 55-2010 during summer occupied hours. A value of 1 means within (inclusive) the limits, i.e. the zone operative temperature is no more than 3.5°C from than the ASHRAE 55 Adaptive model temperature. A value of 0 means outside the limits (i.e. uncomfortable).

Discomfort Summer CEN 15251 Adaptive Category I - reports whether the operative temperature falls into the Category I (90% acceptability) limits of the adaptive comfort in the European Standard EN15251-2007 during occupied hours when the running mean outdoor air temperature is higher than 10°C. A value of 1 means within (inclusive) the limits, a value of 0 means outside the limits.
Discomfort Summer CEN 15251 Adaptive Category II - reports whether the operative temperature falls into the Category II (80% acceptability) limits of the adaptive comfort in the European Standard EN15251-2007 during occupied hours when the running mean outdoor air temperature is higher than 10°C. A value of 1 means within (inclusive) the limits, a value of 0 means outside the limits.
Discomfort Summer CEN 15251 Adaptive Category III - reports whether the operative temperature falls into the Category III (65% acceptability) limits of the adaptive comfort in the European Standard EN15251-2007 during occupied hours when the running mean outdoor air temperature is higher than 10°C. A value of 1 means within (inclusive) the limits, a value of 0 means outside the limits.

Cost

Capital cost (Building Construction Capex) - The basic cost of the building and site construction . This is the only construction cost option available when the cost model is set to 1-Basic.
Capital cost (Building + Design Capex) - The cost of the building + site construction plus the design, overhead and contractor profit costs. This option should only be used when the cost model is set to 2-UNIFORMAT II or 3-NRM1.
Capital cost (Total Capex) - The cost of the building + site construction plus the design, overhead and contractor profit costs + cost of risk and inflation etc. This option should only be used when the cost model is set to 2-UNIFORMAT II or 3-NRM1.
Operational cost (Opex) - annual cost of the fuel used to operate the building. To use the this KPI you must set up tariff data on the Economics model data tab and have the Detailed HVAC model option set.
LCC total present value - The life-cycle cost calculated by EnergyPlus including the construction cost based on the selected cost model. To use the LCC KPI you must set up tariff data as well as construction cost data in the model. This KPI requires settings on the Economics tab and the Detailed HVAC model option.

Important note: The Operational cost (Opex) and LCC total present value KPIs both require settings on the Economics model data tab be made, which in turn requires the Detailed HVAC model option to be used.

Tip: You can carry out powerful analyses to simultaneously optimise whole life cycle cost and whole life cycle environmental impact performance using DesignBuilder's optimisation tools. Choose the LCC and LCA KPIs for this sort of analysis.

Daylight

No daylight-specific KPIs are available in current versions of DesignBuilder.

Energy and Loads

Net site energy is the net energy consumed on site (total site fuel consumption minus any on-site generation). For Simple HVAC, this value is affected by the COP values set on the HVAC tab and is calculated as the sum of the fuel consumption minus any generation. In Detailed HVAC it is the value reported in the Summary ABUPS report, i.e. the sum of the fuel consumption minus generation.
Net primary energy is the net primary energy due to energy consumed on site (total minus any on-site generation). This output should only be selected when using Detailed HVAC.

Total site energy is the total gross energy consumed on site. For Simple HVAC, this value is affected by the COP values set on the HVAC tab and is calculated as the sum of the fuel outputs. In Detailed HVAC it is the value reported in the Summary ABUPS report which is also the same as the sum of the fuel consumption reported in the DesignBuilder results.
Total primary energy is the total primary energy due to energy consumed on site. This output should only be selected when using Detailed HVAC.
Heating (Electricity) - electricity consumption used in heating
Heating (Gas) - gas consumption used in heating
Heating (Oil) - oil consumption used in heating
Heating (Solid fuel) - solid fuel consumption used in heating
Heating (Bottled Gas) - bottled gas (e.g. propane) consumption used in heating
Heating (Other fuels) - Other fuels (e.g. biofuel) consumption used in heating
Plant heating - equivalent to the Zone Sensible Heating output, the overall sensible heating effect of any air introduced into the zone through the HVAC system including any 'free heating' due to introduction of relatively warm outside air and the heating effects of fans.
Heating load - same as Plant heating above.
Cooling (Electricity) - electricity consumption used in cooling
Cooling (Gas) - gas consumption used in cooling
Cooling (Oil) - oil consumption used in cooling
Cooling (Solid fuel) - solid fuel consumption used in cooling
Cooling (Bottled Gas) - bottled gas (e.g. propane) consumption used in cooling
Cooling (Other fuels) - other fuel (e.g. biofuel) consumption used in cooling
Cooling energy - sensible + latent cooling transfer to the supply air from the AHU cooling coil + any single zone unitary and fan coil units in the building.
Cooling load - same as Cooling energy, above.
Plant cooling - equivalent to the Zone Sensible Cooling output, the overall sensible cooling effect on the zone of any air introduced into the zone through the HVAC system. It includes any 'free cooling' due to introduction of relatively cool outside air and the heating effect of any fans present.
DHW (Electricity) - electricity consumption used in DHW
DHW (Gas) - gas consumption used in DHW
DHW (Oil) - oil consumption used in DHW
DHW (Solid fuel) - solid fuel consumption used in DHW
DHW (Bottled gas) - bottled gas (e.g. propane) consumption used in DHW
DHW (Other fuels) - other fuel (e.g. biofuel) consumption used in DHW
AHU heating energy - energy supplied by the AHU heating coil when using Detailed HVAC data.
Fans - fan energy consumption
Pumps - pump energy consumption
Preheat energy - energy supplied by preheat coils to temper the outside air before it enters the outside air mixing box when using Detailed HVAC data.
Reheat energy - total reheat energy
Radiant heater energy - total radiant heater energy
DHW - total DHW energy
Process energy - total process energy to zones
Catering energy - total catering gains to zones over the simulation period

Lighting Energy - total lighting energy consumption over the simulation period
System Fans - System fan energy consumption to zones over the simulation period
System Pumps - System pump energy consumption
System Misc - System miscellaneous energy consumption
Electricity - total annual electricity consumption
Gas - total annual gas consumption
Oil - total annual oil consumption
Solid - total annual solid fuel (typically coal) consumption
Bot Gas - total annual bottled gas fuel consumption
Other - total annual other fuel consumption
Heat Rejection - heat rejection energy by the chillers, e.g. through cooling towers, ground heat exchangers, fluid coolers.
Generated Electricity - total electricity generated by solar PV and wind.

Sys sens heating - total sensible heating provided by HVAC components to the air stream and zones.
Sys sens cooling - total sensible cooling provided by HVAC components to the air stream and zones.
Sys lat heating - total latent heating provided by HVAC components to the air stream and zones.
Sys lat cooling - total latent cooling provided by HVAC components to the air stream and zones.
Room units -
Air heating coils -
Air cooling coils -
Heat rec sens heat - total sensible heat recovered by heat recovery systems.
Heat rec total heat - total sensible + latent heat recovered by heat recovery systems.
Heat rec sens cool - total sensible cooling energy recovered by heat recovery systems.
Heat rec total cool - total cooling energy recovered by heat recovery systems.
Chiller load - Net annual chiller load is calculated as Chiller load – Chiller evaporator cooling rate [kWh]
Room Electricity - Electric energy consumed by zone equipment such as computers, office equipment etc.
Room Gas - Gas energy consumed by Miscellaneous, Catering and Process zone equipment.
Room Oil - Oil energy consumed by zone equipment.
Room Solid - Solid fuel energy consumed by zone equipment.
Room Bottled Gas - Bottled gas energy consumed by zone equipment.
Room Other - Other energy consumed by zone equipment.

Environmental impact

Operational CO2 emissions - annual operational carbon emissions due to fuel consumption in the building. Fuel consumption is calculated through an EnergyPlus simulation. Carbon emissions are calculated from fuel consumption using the Carbon emission factors on the Legislative regions dialog.

LCA (Simple) - Life Cycle Analysis giving the net total lifetime carbon emissions. The sum of the total embodied carbon + operational carbon emissions due to burning of fuel minus beneficial impact of on-site energy generation calculated over the assumed lifetime of the building. Some settings for this including the LCA time of study can be found on the Carbon tab of the Model data dialog. LCA (Simple) is calculated simply as Embodied CO2 + Years of study x Annual Operational CO2 emissions.
Embodied CO2 - total embodied carbon as reported on the Cost and Carbon tab.

Heat gains

Display lighting gains - total task + display lighting gains to zones over the simulation period
General lighting gains- total general lighting gains to zones over the simulation period
Misc gains - miscellaneous gains to zones over the simulation period
Mach gains - process gains to zones over the simulation period
Cooking gains - catering gains to zones over the simulation period
Computer gains - computer gains to zones over the simulation period
Occupancy gains - occupancy gains to zones over the simulation period
Solar gains internal Windows - solar gains to zones through interior windows over the simulation period
Solar gains external Windows - solar gains to zones through exterior windows over the simulation period

Glazing gain - thermal conduction gains through windows
Walls gain - thermal conduction gains through walls
Ceilings gain - thermal conduction gains ceilings
Floors gain - thermal conduction gains through floors
Solid floors gain - thermal conduction gains through ground floors
Partitions gain - thermal conduction gains through partitions
Roofs gain - thermal conduction gains through roofs
Rooflights gain - thermal conduction gains through rooflights
Ext floors gain - thermal conduction gains through exterior floors
Sens cooling energy - sensible only cooling transfer from the cooling coil to the supply air.
Ext airflow gain - sensible gain due to all external airflow including natural ventilation through openings and infiltration through cracks when using Calculated natural ventilation.
Ext infiltration gain - sensible gain due to infiltration air when using scheduled natural ventilation.
Ext nat vent gain - sensible gain due to natural ventilation air when using scheduled natural ventilation.
Ext mech vent gain - sensible gain due to mechanical ventilation air when using scheduled natural ventilation and Room ventilation model option.

Unmet loads

The unmet load hours KPIs described below are the same values as those reported in the EnergyPlus Summary report. The Unmet load hours are described in more detail in the ASHRAE 90.1 Appendix G PRM Reference topic and also in the DesignBuilder LEED and ASHRAE 90.1 Appendix G User Guide.

Unmet load hours all - number of hours where the heating or cooling setpoints were not met over the simulation period for the whole building.
Unmet load hours heating - as above but for cooling only.
Unmet load hours cooling - as above but for heating only.

Custom script

In DesignBuilder v7.0 and later, you can add your own custom script KPIs which allow you to read and, if necessary post-process, simulation results from any EnergyPlus output file or other source and write it to a specific database table using the API. You can use either CS-Script or Python scripts to do this. Note that the name you give to your Custom script KPI is important as it will be used to reference it in the script that you write.

The Custom script mechanism works as follows. For each simulation:

In the AfterEnergySimulation hook that is called immediately after the simulation has been completed and results have been loaded to DesignBuilder, the script must create a new site level table called "ParamResultsTmp". It is necessary to first remove any existing table of the same name.
The "ParamResultsTmp" table has 2 fields.
Records should be added to the table, one for each custom script KPI used in the simulation.
The first field in each record (index 0) should match the name of the KPI, the second field (index 1) should be the value to be read for this KPI for the current simulation.
DesignBuilder reads the table after the script has finished executing and results are loaded to the parametric (optimisation, UA/SA or parametric analysis) system.

Note: While all simulations will call the AfterEnergySimulation hook, only parametric simulations actually read the ParamResultsTmp table created in the script.

The easiest way to understand how custom script KPIs works is to follow through the Custom Script KPI tutorial which explains all of the steps involved.

User defined

No user-defined options are currently available.