With the Internet of Things (IoT) already hyped to become the next big thing for building service management, along comes another interesting acronym for discussion: PoE.
Chris Bedford, Managing Director of Open Technology and developer of the LiGO intelligent lighting system shares his thoughts on the matter.
Power-over-Ethernet, or PoE for short, is another technological development tipped to change our built environment as we know it.
PoE means passing both power and data by using twisted pair ethernet cabling, thus enabling a single cable to provide both data and electricity. This has obvious advantages for devices such as wireless access points for wifi or security cameras.
The reason PoE is being touted for lighting is thanks to LED lighting, which has proliferated around the world thanks to the lower energy consumption compared to traditional lighting. With the LED electrical load being so low that it could be powered with network cables, it was inevitable the discussion would turn to powering the lights in our built environment via the ethernet.
Manufacturers have already released products that use PoE to connect office light fixtures to the building’s IT network. But questions linger over the real benefits for building owners and the industry.
The big selling point of such systems is that building users, namely office workers, will be able to control the building’s services via their smartphones. Under this system office lighting fixtures, when fitted with sensors, capture data on occupancy, temperature and humidity. Building managers can use the data to better set up the building to save energy.
In terms of lighting, we already have systems such as DALI that can do this.
Manufacturers say one benefit is the cost saving from ethernet power needing less wiring than normal cabling. This then begs the question: just how much load is available and at what cost? In a typical office the connected load with sensors and light switch can be over 200 watts, trivial for a lighting circuit at 230volts but that load through an IT switch?
Another promised benefit of Ethernet lighting is that it allows for two way data communication, from room sensors installed at light fixtures. Again, something we have already using DALI.
Few or perhaps no luminaires will ever need big data rates and there are much simpler systems that already provide enough data to control a lamp via traditional mains wiring – which, let’s not forget is how we already deliver power to just about every building light in the world.
Power-over-Ethernet systems don’t come cheaply either, is all this worth it for office workers to be able to turn the heater off with their mobile?
So what does PoE have to do with IoT? Well, the current debate certainly smacks of how the industry talks about how the internet of things will revolutionise our building services.
Big hype: Internet of Things
You might remember last year I highlighted some concerns about the hype around IoT-controlled lighting systems.
The idea that smart buildings, with all services and appliances communicating with each other and the people inhabiting them via wireless internet connection is nothing if not ambitious.
One issue is the uncertainty around skills. Will the next generation of electrical contractors have the capacity or will for programming and commissioning when the majority of installers are not even DALI competent. Will companies pay for this reskilling, or will the customer?
While we’re talking vulnerabilities, security risks are also a major concern. So far most people’s IoT experiences have been with home appliance applications, like Nest, that allow things like using your smartphone to turn on the heating or switching on the coffee machine.
In the event of the wifi going down, the worst-case scenario might be making your own coffee in the morning. But as the BBC recently highlighted, the results would be much worse if the same happened in a hospital or an old persons home for example.
Andrew Kelly, principal security consultant at defence company Qinetiq told the BBC that: “In all cases, pretty much without fail, these (building management) systems had been procured without thought to how to make them secure. I was absolutely shocked. Almost anyone can set up as a BMS installer – it is a bit like taking your car to a garage with mechanics with no qualifications.”
Who takes responsibility for this network and the management of such systems remains to be seen and the extra level of complexity created will continue to pose questions for contractors employed to install them.
Of course when we discuss the future of lighting systems, inevitably the future of Dali comes up. Lighting control manufacturers embraced it as an open standard, with building owners able to maintain systems through the life of the building. Dali is still the industry’s best standard and with Dali 2 coming this year to fill the gaps in the original standard and add new features, it has good days ahead of it.
PoE and IoT are certainly interesting developments. But at the end of the day, the market for building management systems should be driven by responding to actual customer demand, rather than technology for technology’s sake.
Our industry must look to the future to develop the best solutions for customers and building users, but we can’t lose sight of our industry’s core competencies and how we serve our customers today.