Most businesses operate from a building and spend massive amounts of time on planning their business strategy, maximising productivity and conducting the business end of business. The building they occupy is the face of that business and the comfort conditions of that building are directly related to the well-being and productivity of their staff. So from a pure comfort point of view, Building Automation for the control of comfort conditions is important.
Control of the comfort conditions in a building is referred to as HVAC control (Heating Ventilation Air-conditioning Cooling) – this is one aspect of Building Automation.
If we look behind the fabric of a building we will find a number of systems, each with a very specific function.A couple of examples are: Electrical system for plugs, another electrical system for lights, another for hot water geysers. Air conditioning systems for chilled and hot water (different to the geysers) as well as supplying conditioned air into the building – this is called the air conditioning primary plant.
There is a secondary air system that provides pre-conditioned air from the primary plant to the floors and makes changes to the air temperature and air quantity in each room to ensure that the room temperature and air quality are maintained. This is a sample of the number of systems in a building – each with a specific function. For the building to operate efficiently, the various systems need to be controlled to achieve optimum comfort with minimal energy.
As the outside air changes, the primary and secondary air systems must match that change by using more or less cooling or heating. These changes are dynamic and affected by many factors such as occupancy levels, heat gain from the sun as it moves over the building, outside air temperature etc. The changing dynamics have an energy demand to compensate – more cooling or heating requires more energy (electricity).If there is a building automation system, these changes can be optimised to reduce the energy used.
All in all, if you are concerned with the running costs per square meter then the answer is “Building Automation is a necessity”. If you are concerned with the indoor air quality and productivity of the tenants then the answer is “Building Automation is a necessity”.
If you have access to cheap energy and are not interested in the indoor air temperature and quality then automation might not be for you.
The scenario described above is an example of a few systems in a building. In real terms, Building Automation covers every electrical system in a building. Lights, Energy quality (Power factor), Emergency power (Generators), Solar Power and then on to Access Control, Life Safety, CCTV etc.
With a well-designed Building Automation system these disparate systems are able to interact with each other to provide a better, safer and more manageable environment with the added benefits of reduced energy costs, reduced carbon footprint and improved green star energy rating.
Benefits
Building Automation has a few major benefits – energy efficiency and responsiveness (the building is able to automatically correct changes without human intervention) along with this comes the ability to use data from different systems to achieve very simple yet effective cost savings.
An example – Use the passive infrared from the intrusion system to automatically switch the lights off after 7pm if there is no movement.
Sounds simple and it is-implement this in a building that has no automation and you will need to install another system to achieve this because the intrusion equipment cannot communicate.
The example given illustrates that a building automation system allows for each element that is connected to be measured, logged and controlled. This is all handled via a set of rules that are applied in the controllers. If a new set of rules is required, the controller programming need to be adjusted and the job is done. No need for rewiring and re-installation.
Just as the internet and Google has opened the world of data to allow everyone with access to a computer to know everything about everything, a Building Automation system allows you – the building owner – to know everything about your building.
If that knowledge allows for reduced energy consumption, maintenance intervention (preventative maintenance) before major capital plant and equipment fail then the cost of implementation is worth it.
Key factors for consideration
Building Automation or Building Management Systems (BMS) need to be carefully considered to ensure the system provides the desired results. Each sub system in the building must be considered and a matrix drawn detailing the benefits if a BMS system is added to that sub system. In theory, every piece of equipment that uses electricity can be added to the BMS system. Example below
1. Primary Air Conditioning – Yes Energy and comfort
2. Secondary Air Conditioning – Yes Energy and comfort
3. Electrical – Plugs and electrical reticulation – No
4. Electrical Lights – Yes – energy saving occupancy control through intrusion system
5. Electrical Geysers – Yes – energy saving time schedule control to disable over weekends and holidays
6. Intrusion Detection- Yes – for lighting control
7. Life Safety (Fire Detection) – Yes -no energy savings but improves building response in case of emergency
8. IT (Computers,Servers) – IT room to be on BMS but no other requirements
9. CCTV – Yes – allow for control of lights based on specific incidents
Once the high level system matrix is complete, a framework for the system can be put together. It is very important that the system framework allows for integration of each sub-system at the early stages of design. Each sub system will have a number of suppliers for the equipment – the equipment will also have specific technical capabilities and these capabilities are price dependant. If the decision is taken to purchase equipment without considering its eventual integration into a BMS then, at implementation stage the reality that integration will not be possible will come as a surprise. Planning through the use of professional service providers that specialise in Building Automation design is a key factor in a successful implementation.
Scope of Areas
If we look at the Mechanical, Electrical and Audio Visual then the following equipment should be considered.
1. Air Conditioning – Primary and Secondary Plant
2. Electrical Lighting – Internal and External
3. Energy Management –Power Factor, Maximum Demand, Generators, Solar and other sources
4. Lifts and Escalators
5. Sumps and Tank levels
6. Intrusion Detection
7. CCTV
8. Access Control
9. Audio Visual (Boardrooms, meeting rooms etc)
10. IT (Data Centers / IT room environment monitoring and control)
Trends in Building Automation
Building Automation has become a mature industry and with this maturity the implementation of international standards. Standards are designed to improve the industry by implementing rules that are product agnostic. When BMS first appeared, each manufacturer designed and manufactured equipment that worked as an isolated system – could not communicate to other systems and only that manufacturer could be used on that system – effectively the equipment supplier locked the customer in for the life cycle of the equipment. Standards changed this by ensuring manufacturers designed equipment that could communicate using a common wiring standard and common protocol (language). Much the same as ethernet became the standard in the IT industry with IP (Internet Protocol) the standard language for the internet.
These standards allow for multiple companies to develop toward a common goal with resulting lowering of prices as more and more equipment is made available. The standard in Building Automation isBACnet –an open protocol defined by ASHRAE, the American Society for Heating, Refrigeration, Air-conditioningEngineers. A parallel standard Lonworks is available however has not gained the international momentum of BACnet. When implementing a Building Automation System one of the key aspects of design be that ALL equipment must conform to industry standards.
These standards allow for the equipment to be connected to a common network and share data thereby enabling the various systems to interact with each other. A number of new trends such as IoT (Internet of things), Big Data (analysing the data from all of the systems to pick up trends or make new rules) as well as ReST (Representational State Transfer ) are the topics that everyone in the industry is talking about. The most important is that the building has a system designed to industry standards that uses open protocols. This will allow these new devices to be connected and interact via either directly or through cloud based services.
Standard of Work
Building Automation Systems are great if they work, conversely, they are a problem for all concerned if they do not. So how do we ensure a working system when looking at a BMS. The starting point is design – design by professionals that know the industry and the applicable standards. With a well-defined scope of works, data points list and defined equipment specification, the process can begin to find a contractor or System Integrator (SI) to install the system. Selecting the SI is very important – theymust be able to provide the necessary certification showing they are trained industry professionals –as an example:
iLEDhave a certified training institute in South Africa for Distech and Niagara4. The candidates from iLED University are issued with an international certification on completion of the courses. The appointment of an SI that is certified and has a track record as well as the support of the international suppliers is important. As an example iLED are the master distributers for Distech Controls in South Africa – they import and distribute to System Integrators (SI’s) who in turn provide systems to the end user or building owner. If the SI has a problem on site, iLED have engineers available to assist with additional support from our international suppliers in France. This multi-level support is important for the successful implementation of a BMS system.
With a well-defined specification and competent SI, the next item to consider for a successful system is the attention given at commissioning stage. Documenting that each Input and Output has been checked and tested and the location of the transducer is correct and installed to applicable standards is very important. This documentation also forms the basis of building certification by the green building council (GBCSA). With the above basic steps followed the client is assured of a system that will perform as expected.
State of the industry
While building Automation has always been seen as a luxury, the opposite is true. Building Automation is a necessity if the building owner wants to manage the energy consumption per square meter. It is also important for reducing the carbon footprint of the building and achieving “Green Building” ratings. In South Africa, BMS systems are not regulated as for example in Europe where regulations enforce the installation of a BMS in new and existing buildings.
The BMS industry is evolving and moving away from traditional “Air-conditioning Controls Contractors” to more of an integration role – where the systems Integrator (SI) provides the service to link equipment that is supplied complete with controls into an integrated framework. The SI is also integrating the other disciplines – Fire, Intrusion etc. to provide a single dashboard for all the systems in a building. Gone are the days of 10 monitors in a control room each with their own operator procedures and instructions – welcome to the new world of Integrated Building Management Systems.
Ivan Potter is the Managing Director of iLedControl, a South African based company that provides building automation solutions
