The energy efficiency assessment of commercial buildings must encompass both the thermal efficiency of the building fabric and also the energy efficiency of the services such as the lighting and air-conditioning.
Commercial buildings vary between class and type of usage and therefore specific assessment methods have been developed to assess the different classes. AEEBC has extensive experience in performing energy efficiency assessments for commercial buildings.
(Left: Example of a commercial energy efficiency report cover page provide by AEEBC)
There are two main ways to perform an energy assessment for new / and renovated Class 3, 4, 5, 6, 7, 8, 9 commercial buildings: Deemed to Satisfy Assessment (DTS) or Commercial Building Assessment Software.
Deemed to Satisfy Assessment (DTS).
A commercial deemed to satisfy assessment is suitable for all commercial building classes 2-9 and is generally the easiest and quickest way to get your design assessed for building license. This type of assessment method looks at the following elements; Building Fabric, Glazing , Air Movement, Air Leakage, Mechanical Services, Electrical Services, Hot Water Supply and Access for Maintenance. Each element must be assessed individually and comply with minimum requirements. AEEBC can assess your design and provide all the information required for the completion of a deemed to satisfy commercial assessment such as minimum insulation levels, glazing required and proper design of electrical and mechanical services. For examples of past Commercial DTS projects click here.
Home Energy Rating Software (E.g. FirstRate, BERS PRO, AccuRate)
This type of assessment method is used to comply with JV1 and is only suitable for a Class 2 Sole-Occupancy & Class 4 part of a building. Each unit must be assessed individually and compliance with a Class 2 Sole-Occupancy & Class 4 part of a building (other than its services) is verified when:
- each sole-occupancy unit has an energy rating of not less than three stars and;
- the average energy rating of all of the sole-occupancy units is not less than 3.5 stars (for climate zones 1-3) and 4.0 stars (climate zones 4-8).
Home Energy Rating Software such as FirstRate, BERS PRO and AccuRate are suitable for these types of assessments. It must be noted that HERS software cannot be used to assess the services of a commercial building and separate verification is required (this is generally done through a partial deemed to satisfy assessment of the proposed services).
For examples of past projects click here.
Commercial Building Assessment Software (E.g. ESPII / BEAVER, DOE2, Energy Plus).
JV2 Assessment – Verification Using a Stated Value
A JV2 assessment is suitable for specific Class 3, 5, 6, 8, and 9a, 9b and 9c buildings and involves the analysis of both the thermal performance of the building’s envelope and the thermal efficiency of its services and the way they interact with each other. This type of assessment calculates the annual energy consumption of the building (taken as an average across the whole building area) and compares the calculated annual energy consumption with a “stated value” specified in the BCA.
Two simulations must be considered for a building to comply with JV2. These are:
JV2 (a) (viii) the annual energy consumption of the proposed building with the proposed services is not more than the annual energy consumption “stated value” allowance specified in Table JV2; and
JV2 (a) (viii) the annual energy consumption of the proposed building with its services modelled at the minimum standard specified in the Deemed-to-Satisfy Provisions. Again the annual energy consumption must be not more than the annual energy consumption “stated value” allowance specified in Table JV2. However, this scenario is also modelled to prevent the envelope from being downgraded for “enhanced” building services.
JV3 Assessment – Verification Using a Reference Building
Like verification method JV2 this method is suitable for specific Class 3, 5, 6, 8, and 9a, 9b and 9c buildings and involves the analysis of both the thermal performance of the building’s envelope and the thermal efficiency of its services and the way they interact with each other. JV3 differs from JV2 in that the user calculates their own annual energy consumption allowance instead of comparing against a tabulated “stated value” for energy consumption. This is done by modeling a reference building which complies with the deemed to satisfy provisions and other BCA requirements. This sets a benchmark to compare; a) the proposed building with proposed services and b) the proposed building with deemed to satisfy services.
A JV2 & JV3 assessment must be performed by experienced software users and requires information on the architectural design of the building and also the proposed services to be used in the building. There are several types of computer software programs developed to perform these complex calculations, these include: (DOE2, BEAVER / ESPII, Energy Plus, etc.). The staff at AEEBC are fully trained and highly experienced in the use of JV2 and JV3 assessment software’s and have completed assessments on many large commercial projects. Examples of past projects we have assessed include offices, retail shops and restaurants, warehouses and storerooms. (For examples of past JV2 / JV3 projects click here.
