Specification 34 Modelling parameters for J1V3
S34C1 Scope
This Specification contains the required modelling parameters for J1V3.
S34C2 Reference building
The annual greenhouse gas emissions must be calculated for the reference building in accordance with the following:
The reference building mustβ
comply with Deemed-to-Satisfy Provisions in Parts J4 to J8; and
have the minimum amount of mechanical ventilation required by Part F6.
The external walls must have a solar absorptance of 0.6.
The air-conditioning mustβ
for 98% of the annual hours of operation, achieve temperatures betweenβ
18Β°CDB to 25Β°CDB for conditioned spaces with transitory occupancy; and
subject to (ii), 21Β°CDB to 24Β°CDB in all other conditioned spaces; and
if the proposed building has no mechanically provided cooling or has mixed mode cooling, have the same method of control and control set points for non-mechanical cooling as the proposed building.
The infiltration rate in each zone must beβ
0.7 air changes per hour throughout all zones when there is no mechanically supplied outdoor air; and
0.35 air changes per hour throughout all zones at all other times.
The artificial lighting must achieve the required maximum illumination power density in Part J7 without applying the control device adjustment factors.
Minimum Energy Performance Standards must be applied to services not covered by Parts J6 to J8.
S34C3 Proposed building and reference building
(2) For the purposes of (1)(b), greenhouse gas emissions factors must be based on eitherβ
the factors in Table S34C3; or
the current full fuel cycle emissions factors published by the Australian Government, except, where the greenhouse gas intensity of electricity is less than half the greenhouse gas intensity of natural gasβ
electricity is to be weighted as 1; and
natural gas is to be weighted as 2.
(3) For the purposes of (1)(c), location must be eitherβ
location where the building is to be constructed if appropriate climatic data is available; or
the nearest location with similar climatic conditions, for which climatic data is available.
(4) For the purposes of (1)(f), building form must includeβ
the roof geometry; and
the floor plan; and
the number of storeys; and
the location, extent and configuration of ground floors and basements; and
the size and location of glazing; and
external doors.
(5) For the purposes of (1)(h), fabric and glazing must includeβ
quality of insulation installation; and
thermal resistance of air films including any adjustment factors, moisture content of materials and the like; and
dimensions of external, internal and separating walls; and
internal shading devices, their colour and their criteria for operation.
(6) For the purposes of (1)(i), services must includeβ
range and type of services and energy sources, other than renewable energy generated on site; and
assumptions and means of calculating the temperature difference across air-conditioning zone boundaries; and
floor coverings and furniture and fittings density; and
internal artificial lighting illumination levels; and
internal heat gains including people, lighting, appliances, meals and other electric power loads; and
air-conditioning, including chiller, fan and boiler equipment, system configuration and zones; and
profiles for occupancy, air-conditioning, lighting and internal heat gains from people, hot meals, appliances, equipment and heated water supply systems based onβ
Specification 35; or
NABERS Energy simulation requirements; or
Green Star simulation requirements; or
the actual building ifβ
the operating hours per year are not less than 2 500; or
the daily operating profiles are not listed in Specification 35; and
supply heated water temperature and rate of use; and
infiltration values, subject to (7); and
sequencing for water heaters, refrigeration chillers and heat rejection equipment such as cooling towers; and
representation of clothing and metabolic rate of the occupants; and
control of air-conditioning exceptβ
the reference building must have variable temperature control for chilled and heated water that modulates the chilled water and heated water temperatures as required to maximise the efficiency of the chiller or boiler operation during periods of low load; and
if the controls for the proposed building are not adequately specified or cannot be simulated, the sample control specifications in Appendix B of AIRAH-DA28 must be used; and
environmental conditions such as ground reflectivity, sky and ground form factors, temperature of external bounding surfaces, air velocities across external surfaces and the like; and
number, sizes, floors and traffic served by lifts and escalators.
(7) For the purposes of (6)(i), the intended building leakage at 50 Pa may be converted into a whole building infiltration value for the proposed building infiltration using Tables 4.16 to 4.24 of CIBSE Guide A if all of the following have been specified:
Additional sealing provisions to those required by Part J5.
An intended building leakage of less than 10 m3/hr.m2 at 50 Pa.
Pressure testing to verify achievement of the intended building leakage.
Energy Source | ACT | NSW | NT | QLD | SA | TAS | VIC | WA |
---|---|---|---|---|---|---|---|---|
Electricity | - | 236 | 162 | 254 | 101 | 44 | 279 | 191 |
Gas | - | 51.53 | 51.53 | 51.53 | 51.53 | 51.53 | 51.53 | 51.53 |
S34C4 Services β proposed and reference building
For the modelling of services for the purposes of calculating annual greenhouse gas emissionsβ
system demand and response for all items of plant must be calculated on a not less frequent than hourly basis; and
energy usage of all items of plant must be calculated with allowances forβ
part load performance; and
staging to meet system demand; and
energy usage of cooling plant must be calculated with allowances forβ
the impact of chilled water temperature on chiller efficiency; and
the impact of condenser water temperature on water-cooled plant efficiency; and
the impact of ambient temperature on air-cooled plant efficiency; and
the energy use of primary pumps serving individual chillers; and
the energy use of auxiliary equipment, including controls and oil heating for chillers; and
thermal losses in the chilled water system; and
the impact of chilled water temperature on thermal losses in the chilled water system; and
energy usage of water heating systems for space heating must be calculated with allowances forβ
the impact of water temperature on water heater efficiency; and
the energy use of primary or feedwater pumps serving individual water heaters; and
thermal losses in water heating systems; and
the thermal mass of water heating systems, accounting for thermal losses during periods when the system is not operating; and
energy usage of fan and pump systems must be calculated with allowances forβ
the method of capacity regulation; and
the use of either fixed or variable pressure control; and
energy usage of pump systems must be calculated with allowances for the system fixed static pressure head; and
energy usage of auxiliary equipment associated with co-generation and tri-generation systems, including pumps, cooling towers and jacket heaters, must be calculated; and
where the energy usage of the heated water supply for food preparation and sanitary purposes or the energy usage of lifts and escalators is the same in the proposed building and the reference building, they may be omitted from the calculation of both the proposed building and the reference building; and
energy use of a lift in a building with more than one classification may be apportioned according to the number of storeys of the part for which the annual greenhouse gas emissions and thermal comfort level are being calculated.
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