Image credit: Steve Douglas/Unsplash
By Eamonn Ryan
The control of a building’s heating, ventilation and air conditioning system (HVAC) has over the years morphed into Building Management Systems (BMS) which has become an entire industry in itself.
The purpose of a BMS is to control and monitor large energy consuming systems within a building, such as HVAC, lighting, fire and security systems. With advances in technology such systems are just as viable in smaller buildings as they are in larger ones. The benefits are to maintain occupant comfort and ensure occupant safety, all the while delivering energy efficiency and lower operating costs.
Many commercial and industrial facilities were built in an era when technology really came as an afterthought. That was attributable at that time to a lack of feasible technology options which could make managing a building simpler and more efficient. That has all changed. Fast-forward 40 years and the industry today features advanced solutions that, short of running a building on auto pilot, offer efficient, optimised and sustainable solutions that catapult facilities into a new era of sophistication.
Bruce Kinnear, BMS sales manager, iLED Building Automation. Image credit: © Eamonn Ryan | RACA Journal
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Typically, sensors and control signals will be hardwired throughout a building at the time of construction for cost control purposes. Once a building is complete and in operation, retrofitting a BMS system is more costly and disruptive, not to mention putting a strain on the original system capacity. However, it is being done.
| Most of a building consists of mechanical plant, highlighting the relationship between BMS and HVAC&R.
A BMS enables a digitally connected building which offers 24/7 support for:
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How it works
The methodology of BMS, whether addressing buildings old or new, is to measure, analyse and put in place systems of control. In the instance of an older building, the key factor is to measure how it uses its energy and how technology can help to optimise energy consumption through metering and monitoring, coupled with smart devices and analytic software. This is a fundamental part of a building’s journey to a digital strategy.
In a digitised building, each vital cog continuously provides the data required to obtain operational insight. That data in turn enables analysis for service providers to take advantage of best-in-class operation (OT) and IT solutions which unlock the performance of buildings and maintenance of their facilities remotely and proactively. This results in reduction in both energy use and unscheduled maintenance, as well as extends the life of assets.
Bruce Kinnear, BMS sales manager, iLED Building Automation, says: “Historically, the introduction of systems controls to a building looked initially at the HVAC system – it being the biggest consumer of energy. Later, installers realised the possibility of monitoring all other features of the building such as lighting, generators and more. This came to be known as third party integration. The controls industry does the air conditioning, but BMS has become the umbrella function while the driving force has changed to being primarily focused on energy efficiency. BMS, through systems integration, is what makes a building a smart building.”
The company iLED is a distributor for Distech Controls and fellow company ZUD is a distributor for Siemens, while the group also manufactures its own range called eZicontrols, which complements Distech and Siemens to form a holistic BMS system. Image credit: © Eamonn Ryan | RACA Journal
i4 Group company iLED is a distributor for Distech Controls and fellow company ZUD is a distributor for Siemens, while the group also manufactures its own range called eZicontrols, which complements Distech and Siemens to form a holistic BMS system. Kinnear says: “We supply product, technology and training to the system integrators of BMS throughout the country. When we do a project, for instance, we take all the information from each unit and visualise it on the BMS. It integrates the generator, the lighting system and the HVAC system, and for instance adjusts the blinds so as to harvest natural light, douses the lighting so it’s mostly natural light, moves the air conditioning setpoint to allow for radiant heat, and more. It is all about saving energy and making the building space ‘green’.
“BMS is a simple Inputs-Outputs (IO) control – it reads temperature or light and increases or decreases the set point of each according to the set code and visualisation data. It provides real data to support the carbon footprint of a building for companies wanting a Green Certificate. All this data resides in the cloud being part of the Internet of Things, which is today being re-labelled the Internet of Everything as the technology expands,” he says.
Energy efficiency is key
“Air conditioning is still the biggest user of electricity in a building. A chiller draws massive kilowatt hours – and when talking about energy saving, most electricity bills are calculated on maximum load multiplied by kilowatt hours. If we can reduce the maximum load by say 20 points we can save money. That can be achieved simply by starting the chiller a little earlier or a little later than when everything else is being switched on, thereby preventing a spike in power usage. Lighting doesn’t draw a lot of power, but it is constant if left on all day and night – unless managed,” says Kinnear. “There is no human interface – the idea is to automate it. If there’s no movement in an office after 5-10 minutes, the lights switch off. Even that technology has evolved to infrared detection.”
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“The payback calculations we’ve done suggest a BMS pays back its capital investment in about two years on an average-sized office block. A properly engineered BMS is like a toolbox: the tools save time. These provide the maintenance manager with visibility before any complaint or problem arises, letting them know exactly where to go and what tools to take. It can go as far as informing what individual component is required to repair a fan. This saves a huge amount of time – and time is money. Saving energy is really a mindset change.”
A BMS is effective for any size building – whether industrial or commercial – but Kinnear emphasises that the payback is typically longer with smaller buildings, as the average cost diminishes the bigger the system.
“In addition, it’s easier to instal a BMS on a new build, as you get to choose appropriate fittings and units better suited to a BMS, whereas with a retrofit you may have to change the fittings if you want that level of interface. For instance, in a new build, you can choose a generator which has a BACnet IP controller.”
BMS provides benefits that extend beyond the financial. It results in an improved experience for the occupants of a building. Kinnear describes it: “With a proper BMS, we monitor air quality so as to be able to improve it when it gets bad. Staff feel better and more energised. Air conditioners can be connected via Bluetooth to an individual’s smartphone so they are in control and can change the set points. How far you want to take the benefits is limited only by your capex budget and your imagination. We can automate everything.”
BMS integration through open systems
A further evolution of BMS has been from proprietary to open systems. Today’s open BMS system integrates multiple systems for centralised, real-time control and management across either single or multiple-enterprise buildings, assisting managers and owners to understand and monitor their facility’s energy usage.
“It was 20 years ago that open protocols came about. Industry decided that all these proprietary communication protocols were locking in clients forever – something skewed in favour of the system provider rather than the user.
“Now we have open protocols like BACnet, Modbus and Dali – but BACnet in South Africa is the primary open protocol. This evolution forced the proprietary companies to change their model – manufacturing products worldwide that integrate with open systems.” Kinnear explains that this is precisely iLED’s business: developing building management systems consisting of a multitude of products that are capable of integration using BACnet or Modbus.
As to where technology is taking the BMS market, Kinnear admits his bias to Distech Controls: “Distech is on the cutting edge of technology. Where technology is rapidly progressing is towards the Internet of Everything (IE), with some doing it better than others. With the Internet of Things, some devices were going on the internet – but with IE every device is going to be connected to everything else. Everything’s becoming smart and communicative – not only your fridge and TV, but your microwave, kettle and everything.”
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BMS is not the domain of the ‘IT guy’ says Kinnear, due to the latter’s obsession with firewalls and passwords. BMS has to work in a more interoperable manner.
“We build our own OT (Operational Technology) structure within a building and link it to the IT guys’ business system – if they need it. It happens that when we plug it into the client’s system as a part of their network, it crashes the entire system because of the volume of data in BMS. So we typically provide them just as much data as they need.”
Sebastian Hills, sales director of Staycold International. Image credit: Staycold
IoT in refrigeration
Sebastian Hills, sales director of Staycold International, says: “We implement technology such as telemetry in our refrigeration units, which allows one to remotely monitor a unit’s condition thereby improving preventative maintenance by showing compressor and fan runtimes. It can also monitor the usage of the unit, ensuring the tavern owner is correctly operating the refrigerated unit – for instance, by taking advantage of the eco energy option at night.
“Our units can be fitted with a device that plugs into our energy management system, which then transmits over the USSD network the unit’s location through GSM triangulation. This is key for larger users in terms of asset management so as to monitor energy consumption of their fleet of units at any one time.”
Hills adds: “Our devices have a remote two-way communication capability. We have complete visibility with all the details of, say, a freezer in a supermarket, with access to the model of the unit, its condition and operation. Some customers want a daily report, and others hourly – it shows, amongst others, the internal cabinet temperature, the condenser temperature, the overall status, loadshedding schedule and many more – essentially whatever the controller knows, you can know including how many times the door has been opened.
“We can change the eco-parameters and also some quite nice things like turning the lights on and off. This can all be integrated into a building management system if the customer requires it to. We currently have our own standalone portal for viewing of data,” he adds.
In conclusion
The future of BMS lies in being in the cloud or it loses all practical application. The second requirement is for it to help building owners and occupants to achieve the sustainable development goals set by the UN, at least not the ones related to the built environment, and to achieve a better quality of life for building occupants, which is the core of our profession as facility managers in HVAC&R. Without smart systems, we can’t have smart buildings, smart communities, or smart cities…
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