In 2006, Britvic sold 1.4billion litres of soft drinks in hundreds of different flavours, shapes and sizes and delivers to over 4000 customers and about 200000 points of distribution;
A recently completed energy efficiency improvement programme at the Britvic Beckton bottling plant has resulted in substantial energy savings and a positive impact on the company's carbon emissions allocation.
The programme employed auditors, Air Compression Technology Ltd to review and make recommendations on improvements to the high-pressure air generation system on site. The recommendations resulted in a new EnergAir control system for each existing piston compressor, the integration of a new compressor and the installation of an overall management, control and PC visualisation package from EnergAir that provides integrated live control and reporting functions for the entire system, including the cooling, air preparation and building ventilation systems.
Kevin Cunningham, on the Britvic site management team comments: "Minimising the environmental impact of our operations is important to Britvic and reducing Energy Consumption is a key aspect of that policy. We were aware that a large part of our energy expenditure is in compressed air and commissioned energy auditors Air Compression Technology (ACT) to benchmark and audit the high-pressure compressed air system during October 2004. ACT collated all the operational data, analysed it and then met with us to discuss the plant operational requirements in detail. From this meeting we were able to establish accurate estimates for the possible savings and create a clear strategy for delivering and maintaining tangible energy, cost and carbon savings."
Graham Coats, Director of EnergAir Solutions Ltd, adds "PET bottling plants tend to work on far higher pressures than normal automated production lines, typically 40bar as opposed to ~7bar, requiring more power and often providing a greater opportunity for energy saving. With the recent rises in energy costs and the experience we had gained form systems we have completed on other PET plants, we were confident significant savings could be realised."
The table below summarises the improvement in system performance since the introduction of the compressor management/control system. The system has achieved the energy gains by optimising the installed compressor set, stabilising the system pressure and allowing a careful but precise reduction in the system operating pressure. Further energy gains are expected in the short term through effective management and fine-tuning of the system.
This installation also presented a number of practical challenges for EnergAir to overcome, not least that the original control cabinets for the four original high-pressure reciprocating piston type compressors had to be replaced in order to update to the new control technology. A recently installed fifth compressor was also integrated into the system and only required the replacement of its PLC controller.
The previous control system required a complex sequenced start-up and shutdown procedure that required a long list of checks and switches to complete. Now, the process has been automated to the point where a single physical start button pressed either locally or on virtually the PC will carry out the complete timed and sequenced start routine including all the parameter checks and power switching. This improvement not only saves time for the operating crew, but it also contributes towards increased plant safety.
The compressor control elements were supplied by (EnergAir sister company) CMC Controls based in Belgium. Once installed, the energy savings are derived from applying a combination of system pressure optimisation principles, matching air generation closely to demand, ensuring compressors are working at their optimum efficiency and only running when they are needed.
Air pressure sensors are fitted throughout the system and used to feed live data into EnergAir 'EnerSoft - Analysis' data manager software that is hosted on an onsite PC, this collates and records all the data and makes it available online to ACT Ltd. where it is compiled into specific Key Performance Indicator (KPI) reports. For day-to-day maintenance monitoring The complete compressed air system, from compressor, through to the dryers, cooling system and out across the plant is represented visually on screen in a Windows XP environment using EnergAir's EnerSoft - Visual software package, with key indicators such as system pressure and efficiency displayed clearly on screen as analogue style dials.
The data is updated every few seconds and so the information seen on screen is virtually live, Britvic are able to predict and plan for any changes made to the plant and report effectively on incremental positive changes made to keep efficiency maximised.
- EnergAir Solutions Ltd is based in Woking, Surrey, UK. www.energair.co.uk. Air Compression Technology Ltd is based in Sandygate, Sheffield, UK. www.aircomptech.com
