User Manual

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The eu.bac certificate and allocation of points to the corresponding levels is depicted below:
Example: eu.bac system label
Level
Points
AA 85-100
A 75-84
B 65-74
C 55-64
D 45-54
E 0-44
Based on the calculation methods described in EN 15232, conclusions can be drawn regarding the
potential for energy savings. An improvement of 10 points corresponds to energy savings of
approximately 5%. These values, of course, depend very much on the individual object to be
evaluated and should be considered as reference values.
The eu.bac label sustains the energy-efficient control of building systems. The certificate is valid for 3
years. Subsequent recertification will be required in order to keep or improve the given rating. When
KPIs have already been in use the recertification would focus only on identified deficiencies and on
areas where modifications to the building or the BACS have occurred.
5.3.4. eu.bac system Key Performance Indicators (KPIs)
The eu.bac method includes continuous, automated evaluation of key performance indicators (KPIs)
which prove that the building systems are controlled at their most sustainable energy-efficient level
while maintaining indoor comfort closely related to building occupants’ satisfaction, health and
productivity. The KPIs are self-adapting to modifications in operational parameters, e.g. if the
operator changes the temperature setpoint, the KPI using this value in the calculation will adapt
automatically the allowed deviation within a defined range.
eu.bac System KPIs detect any deficiencies in the control of energy-consuming technical equipment
in the building. A simple traffic light evaluation (green, yellow, red) allows first level diagnostic without
consulting complicated trend curves.
Example KPI:
· Room / Zone air temperature (heating comfort supervision)
- The goal of the KPI is to generate an alert when the room temperature rises during heat
demand over the comfort zone.
- Approach: Accumulation of time during a day in which the temperature is above the comfort
band in relation to the accumulated usage time.
- The valuation is as follows: If the comfort band is breached while more than 20% of the
usage time red is displayed at 10% to 19% yellow, and less than 10% green.
The key performance indicators enable ongoing assessment of the performance of the building
automation system and its components. With the help of these indicators, operators can detect and
optimise settings that differ from actual requirements. For energy consultants, they also constitute a
reliable data source and are the basis for energy optimisation. The basic principle here is: The
greater the level of instrumentation and the finer the resolution, the more accurate the information,
the more precise the control of the indoor environment; the more individual control the occupant has
on his/her immediate environment.