Optimisation Objective

Accessed from Optimisation Analysis Settings dialog

Name

Your name for the objective for your reference, e.g. "Minimise ASHRAE 55 discomfort hours"

Objective KPI

Select the Objective Key Performance Indicator (KPI) from the list. You can find more detailed descriptions of many of these outputs on the Simulation Detailed Results page.

View the full list of KPIs

Comfort

Discomfort (sum clo) - total discomfort hours when summer clothes are worn (see comments below for Discomfort (all clo))
Discomfort (win clo) - total discomfort hours when winter clothes are worn (see comments below for Discomfort (all clo))
Discomfort (all clo) - total discomfort hours when winter or summer clothes are worn based on ASHRAE 55 method. Area-weighted average values for individual zones are used for the building level assessment. 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. 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 summer occupied hours. 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 summer occupied hours. A value of 1 means within (inclusive) the limits, a value of 0 means outside the limits.

Cost

Capital cost (Capex) - total construction cost as reported on the Cost and Carbon tab.
Operational cost (Opex) - annual cost of fuel used to operate the building.

Daylight

No daylight-specific options are available in DesignBuilder v4.

Energy and Loads

Net site energy - net energy consumed on site (total minus any on-site generation)
Net primary energy - net primary energy due to energy consumed on site (total minus any on-site generation)

Total site energy - total energy consumed on site
Total primary energy - total primary energy due to energy consumed on site

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
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
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.
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.
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
Lights energy - total lighting energy
Process energy - total process energy
Catering energy - total catering gains over the year
Task/display lighting gains - total task + display lighting gains over the year
General lighting gains- total general lighting gains over the year
Misc gains - miscellaneous gains over the year
Mach gains - process gains over the year
Cooking gains - catering gains over the year
Computer gains - computer gains over the year
Occupancy gains - occupancy gains over the year
Solar gains internal Windows - solar gains through interior windows over the year
Solar gains external Windows - solar gains through exterior windows over the year
Plant heating - total zone sensible heating
Plant cooling - total zone sensible cooling

Lighting - total lighting energy consumption
System Fans - System fan energy consumption
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 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 -
Sys sens cooling -
Sys lat heating -
Sys lat cooling -
Room units -
Air heating coils -
Air cooling coils -
Heat rec sens heat -
Heat rec total heat -
Heat rec sens cool -
Heat rec total cool -
Chiller load -
Room Electricity -
Room Gas -
Room Oil -
Room Solid -
Room Bottled Gas -
Room Other -

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.

LCC total present value - Life Cycle Cost based on the settings on the Life Cycle Cost dialog.
Embodied CO2 - total embodied carbon as reported on the Cost and Carbon tab.

Heat gains

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 -
Ext infiltration gain -
Ext nat vent gain -
Ext mech vent gain -

Unmet loads

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.

User defined

No user-defined options are available in DesignBuilder v4.

Minimise or Maximise

Select whether you wish to maximise or minimise the selected objective.