Building Automation and Control Systems (BACS) can have significant impact on energy consumption of buildings and their occupants. In recognition of these facts, the European Committee for Standardization issued "EN 15232:2012 Standard: Energy Performance of Buildings – Impact of Building Automation, Controls, and Building Management" for use in conjunction with the Energy Performance of Buildings Directive (EPBD).
The EN15232 standard includes the following:
- A list of control, automation, and technical management functions that affect the energy performance of buildings
- A method for defining the minimum requirements for the control, automation, and technical building management functions implemented in different types of buildings
- Detailed procedures for quantifying the impact these functions have on the energy performance of a building
- A simplified method to obtain an initial estimate of the impact these functions have on the energy performance of buildings
The methods and procedures described within EN 15232 are based on a system of energy classifications assigned to the various BACS and Technical Building Management (TBM) functions.
The standard covers different automation functions, in particular:
- temperature control
- indoor air quality control
- drivers and motors
- monitoring, technical alarms and power management
- diagnostic information
- central operation and settings
- remote controls
Starting from a building energy audit
The planning of a BACS implementation or upgrade begins with a building energy audit, which can be performed on three levels, depending on the complexity of the building and systems:
- Preliminary Analysis/Walkthrough
- Energy Survey and Detailed Analysis
- Detailed Analysis for Capital-Intensive Modifications
Additional information concerning energy audit are covered by the series of standards EN 16247 while the upcoming series of standards prEN 16946-x will focus on “Inspection of Building Automation, Controls and Technical Building Management”.
Procedure for calculating BACS efficiency
The EN 15232 standard presents two different procedures for determining the impact of BACS functions on the energy efficiency of a building, one through an estimation based on available coefficients and another one more detailed which require more comprehensive information on the building and proposed systems.
Financial assessment of building automation projects
There are two commonly used financial tools for assessing capital investments such as the installation of BACS. The Payback Method is a relatively simple calculation while a more detailed Life Cycle Analysis allow to better assess the benefits long after their costs have been recouped.