The major source of power consumption for most woodworking businesses is the dust extraction plant. In most existing systems, extraction fans run at a constant speed irrespective of the number of woodworking machines that are operating, or the amount of dust to be extracted. They also run continuously throughout the period that the workshop is operational; anything from an eight-hour shift five days a week, to a 24 hours seven days a week operation.
Engineers at Dust Control Systems Ltd (DCS) realised that improving the efficiency of the dust extraction system itself could have a considerable effect on electricity bills. For instance, a minor reduction of 10% in fan speed can yield a 27% saving in energy, while a 20% reduction can reduce electric energy consumption by 50%.
“Our challenge was to take a total system approach rather than a component approach to the development of ‘on demand’ dust extraction systems which would be dynamically responsive, providing optimum extraction volumes, only when needed,” said DCS director, Chris Oldfield. “Today, we have the technology, expertise and know-how to provide efficient systems which can be supplied as new installations or retrofitted to existing plants.”
Optimisation system
DCS secured the exclusive UK distributorship for the ECOGATE system, a proven computerised optimisation system which employs a controller, automatic motorised gates and remote machine sensors. When a machine is turned on, the sensor signals the controller to open the appropriate motorised gate to provide extraction. When a machine stops working, the motorised gate closes automatically. The central control unit, or greenBOX, constantly monitors individual machines and determines the optimum speed of the fan, achieved via a variable speed drive.
Benefits to customers have been dramatic.
Rixonway Kitchens makes more than 12,000 rigid kitchen units a week at its 170,000ft² manufacturing facility in Dewsbury, West Yorkshire. Its existing dust extraction plant at Rixonway Kitchens, also supplied by DCS, comprises a high-efficiency modular chain filter, with an air volume of 180,000m³/hr, and is designed to deal with dust and chips from all production lines. Like most extraction systems, it uses fans that run at a constant speed, irrespective of the number of machines operating or the amount of dust to be extracted.
Following an energy appraisal, DCS demonstrated that energy savings of 56% were achievable by retrofitting an ECOGATE system, with a full return on the investment in approximately two years. A further benefit for Rixonway was that the energy-saving installation would also qualify for an interest-free loan from the Carbon Trust.
The system comprises two ECOGATE greenBOX Master SRL controllers, nine variable speed drives and 28 motorised gates and machine volt sensors. When a machine is turned on, the sensor signals the controller to open the motorised gate of that particular machine to provide extraction.
Real-time statistics
The Master SRL controller displays real-time statistics including motorised gate status, negative pressure readings, electricity savings (current and average) and kW levels for each fan. The system can be monitored and managed via remote internet access, and also includes functions to modify individual fan speeds and variable speed drive programming.
Inscape Cubicles & Washrooms has also retrofitted an ECOGATE system to its existing DCS dust extraction and was able to do so without the need to replace the existing filter, ducting or 37kW main fan.
“It’s an amazing system – you can literally see the variation in real-time power levels on the VSD display,” said Gary Wynne, production director at Inscape. “DCS installed the complete system with little or no disruption to production and our manufacturing team love it because it’s dramatically reduced noise in the workshop.”
“The ECOGATE system is more than living up to expectations,” said Paul Mills, Inscape managing director. “The first couple of months’ savings far exceed those anticipated. At this rate, the savings on electricity will result in an investment payback of around 18 months. Add to this the interest-free loan we received from the Carbon Trust, and the decision to green-up our dust extraction makes good business sense.”
