Belimo Actuators Pty Ltd managing director, Duncan Jenkinson, talks to CCN about the unique features of the Energy Valve that made it one of the hottest products of the year.
He said the Energy Valve was able to set itself apart from the rest of the market because industry has realized energy efficiency isn't simply a product anyone can buy or sell.
“It requires a certain level of expertise. In order to achieve that next NABERS star, or a decent reduction on energy bills, it requires a system of complimentary products working together,” Jenkinson said.
“If you look at the market, particularly when it comes to solving low Delta T syndrome to better achieve efficiency, there are a number of products out there that claim to solve this problem; in reality it is never that simple.
“We know how to solve low Delta T because we know what causes it. It means there is more energy available to a heat exchanger than it can exchange, either through water temperatures that are too cold, flow rates that are too high or air volumes that are too low.
“Due to the dynamic nature of VAV AHUs they often have this problem and we have seen a number of technologies come onto the market promising to be a one stop solution,” he said.
“However, we know that central plant based chilled water reset is fooled by mixed load conditions especially for AHU's serving different thermal zones.
“Equally, plant optimisation that simply increases flow temperatures until a valve is fully open puts the chiller in a less than efficient position by going too low with the loading; even the most efficient chillers will plateau.
“Therefore we need a better system and more data to effectively control the whole building. The device which delivers that data is the Energy Valve.”
Jenkinson said when some clients installed Energy Valves, they thought that this was the end of the journey. “However, you cannot treat energy efficiency like Jenga; it works more like a dot to dot. You get a few components that help deliver the picture but it’s the system overall that has to be configured to deliver the results,” he said.
So how does the energy valve work?
The Belimo Energy Valve is an electronic pressure Independent valve, with BACnet and Modbus capabilities both over IP and RS485. Put simply, it supplies the BMS system with the information it needs to control plant in the most energy efficient manner possible.
The BMS simply looks for the furthest open valve, or 'thermal index' and scales the flow temperatures from that. All the other AHU's Delta T is maintained by the Energy Valve using its patented on-board Delta T manager to ensure good Delta T is maintained at all times.
Pump Control is achieved by looking at the physical rotation of the valve. This is primarily a function of pressure. This point gives the amount of rotation required to deliver the required flow, so the lower the valve position the greater the pressure.
“We can simply look for the hydronic index, such as the most open valve, thus it could be any electronic valve in the system, on a branch fitted to an AHU,” he explained.
“Using this information the BMS simply reduces the pump speed until the furthest open valve is as far open as we would like.
“Bypass control also plays a part with interlocks preventing increases in pump speed or reductions in flow temperatures until the bypass is closed.
“Of course it's not that simple, and each building is different and we have people to help get you and the building ready.”
Contact Belimo on 03 8585 7800