Lately we have been doing a bit of work measuring energy in large buildings and complex sites. Often these are places where there are building management systems that preform many of the low level functions to control the sophisticated network of valves, sensors, actuators, heaters, chillers, machinery, lighting and other things that make a building work.
We have found that building management systems are great at what they do - controlling a sophisticated building, however they can be made to work really well by using SEGmeter and our real time Internet based visualisation to add value in diagnosing problems, fault finding and debugging programs at the heart of the building management system.
Like any complex program, it often takes a few iterations to get things working well just so, and a BMS is just the same. Most buildings we find are configured to work, however often this "working" program while meeting occupant comfort needs hasn't been optimised to be energy efficient, something becoming increasingly important with recent energy price rises.
SmartEnergyGroups.com works very well side by side with a Building Management system to provide an independent view of what is going on, using our sophisticated visualisation techniques to identify trends and drill down to discover operational issues and even at the lowest level identify pump switching from the raw data feeds.
This sort of energy visualisation signature is invaluable for the building management system programmer, who can walk about the plant during mid-programming job with an iPhone or iPad and see in real time the trace of machinery activating based on program adjustments.
Here are some examples of how we have used the system to identify building program issues;
At on site we are working at, there is an issue with the lighting controls, pumping schedules or other machinery where the operating pattern has issues and knowns, the SmartEnergyGroups.com SEGmeter system is being used to help identify these events and trace them back to control or building management system logs to determine what triggers and controls are root cause of the problems.
lighting has been left on over the weekend
Tune plant programing
Recently we have used the system to achieve a significant reduction in energy usage at a large hall space, just one of several at a multi premise site where the SmartEnergyGroups.com system is installed. Before the building management adjustments were made, it was found the plant would run more or less continually, with a minimum average load of 10 kW overnight, with significant step changes as the plant loaded up during the day. A number of iterative improvements were made to the building management programme in conjunction with the feedback from SmartEnergyGroups.com to identify and solve issues with the time program, air handlers, chillers and finally pumps. Since the adjustments, the energy consumption in the facility is significantly reduced.
incremental program inprovements to deliver a significantly reduced plant energy consumption
Early morning overheat.
The system has identified an interesting scenario, where the mechanical cooling system had it's start time delayed as a result of some program modifications. The system identified that the gas fired boilers were overheating the building in the early morning, and when the cooling plant came on line, significant energy was used to cool the overheated building. Once this was identified, action was taken to re-program the gas boiler times in the building management system and as a result the same occupant comfort was achieved with far less energy expenditure.
too hot in the mornings, so the cooling kicks in
Control system failure
There are many components of a buildings mechanical plant, countless relays, PLC's, computer interfaces, and many things that can go wrong. The SEGmeter system is a very simple and reliable technology component, that can detect failure of components by identifying abnormal patterns, failure of a relay or other control mechanism. One example is an incident that was recorded in the mechanical plant, that when it was over, one unit was running a 5kW fan coil continuously. With this identified, it was a simple matter to repair the problem and save a significant amount of wasted energy.
the heatmap shows the fail event on Saturday at 9am
drilling down to the actual failure event
In the end it's not about one system or another, but combining technologies that compliment each other in striving to get the best results from an increasingly scarce energy supply.
What stories do you have that you'd like to share?