Page 43 - Energize September 2021 HR

TECHNICAL

To obtain an EPC, a building owner needs that the spaces in the building are supplied with energy and their relevant net floor areas in
to gather the following building information: comparison to one another.
• Energy consumption data for a year To determine the energy performance rating of a building, all sources of energy consumed
• Net floor area in the building must be considered,whether they are suppied to the building by the grid, gas or
• Information regarding the areas fuel supply line, or generated internally in the building. These energy sources include all forms
excluded of electricity, whether from the national grid or from a solar PV plant, as well as fuel consumed
• Vacancy rate by on-site generators, gas, or even solid fuel such as coal used in the building.
For example, if there are two buildings with the same net floor area, and both buildings
They must then contract a South African consume the same amount of energy per year, but one building acquires part from the grid
National Accreditation System (SANAS) and part from a solar PV plant, while the other building acquires all its energy from the grid,
accredited inspection body (IB) to audit they will both have the same EPC rating.
the information. The IB submits the energy The fact that one building obtains one-third of its energy from a renewable source does
performance value to SANEDI, which not affect its rating. The certificate does however, indicate the energy mix, i.e. the amount of
inputs it into the National Building Energy energy obtained from different sources, such that the fact that the building with a solar PV
Performance Register. plant is less dependent on the grid will be clearly stated on the certificate.
A unique number for the EPC is Although the EPC may be regarded by some as a begrudged compliance measure, it can
generated and sent to the SANAS be an invaluable decision-making tool for improving the energy performance of buildings and
accredited IB, who then issues the EPC to property portfolios.
the client for display. For example, if a portfolio of buildings comprises some with reasonably good ratings and
others with poor ratings, it is more likely that improvements to reduce the energy consumption
Calculation of rating of those with poor ratings would yield better returns on investment than spending money on
EPCs are not based on a simple calculation the buildings which are already performing well.
of the total energy vs. total size of the The impact of the display of an EPC on tenants and prospective buyers is difficult to
building. Depending on the makeup ascertain, but it is fair to anticipate that it could be a significant contributor to the value of the
of the building, portions of the energy building. It is not difficult to imagine that a building with a poor energy performance rating, as
consumption need to be attributed to expressed on the EPC, could be more difficult to sell than a building with a good rating. n
different sections of the building. This
will be determined by the different ways Send your comments to rogerl@nowmedia.co.za

Figure 2: Typical large South African shopping mall

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