Energy Management
Structured Energy Management – Equipment and Processes
So far in this series we have spoken about specific areas of energy usage such as lighting, compressed air and refrigeration. These are common in a number of manufacturing businesses and it is therefore fairly straightforward to provide generic advice in an article such as this.
What do we do then to identify and improve the energy efficiency of our manufacturing process? This is usually more specific to a particular organisation and would therefore seem more difficult to write a generic article about.
However, this is not the case. When you really think about your manufacturing equipment or process the same principles of structured energy management practice can be applied. This article explores some of the opportunities to improve energy efficiency of a piece of manufacturing equipment or a manufacturing process.
The first and most obvious solution is technology. Has the technology moved on and is more energy efficient equipment available that does the same job but more efficiently? This may also improve manufacturing performance in terms of output or quality as well so seems an ideal solution. It may well be, but unfortunately we do not live in an ideal world and capital restraints may prevent this from happening. Similarly, the payback may not be able to compete for the investment against other projects.
The good news is that there is often a lot more that can be done to improve energy efficiency without the need for major capital investment. A few common areas to look at are briefly discussed below.
Firstly think of the equipment (or line) as a number of components of which certain parts consume energy. For example, motors or compressed air blowing nozzles. You can then consider and prioritise which of these are significant and which can be improved. For example, could higher efficiency motors be fitted, could variable speed drives be fitted, could the need for air blowers be eliminated or reduced by doing something different, could pressure reducing nozzles be fitted on the air blowers, etc.
Similarly think about the utilities that feed the equipment e.g. compressed air, refrigerated water or steam. Can the demand for these be reduced or can they be isolated when not in use? Can pipes be lagged to minimise energy loss? Are there leaking joints? Good system design and maintenance can be of significant benefit here.
Lighting is another area. What parts the equipment or line need to be lit. Can this be local or task lighting? What lux level does it need to be?
We spoke in an earlier article about staff behaviour. The importance of engagement with staff on energy efficiency and the training of energy champions is most important here. Your staff usually know the equipment better than anyone else so who better to determine how its efficiency can be improved. The opportunities in this area are usually numerous you just need the staff onboard to be able to get to them. Examples of this could be optimising warm up times, having low energy set back positions during equipment setup, identifying equipment not used or required in the process, identifying equipment that runs constantly even though not required all the time e.g. conveyors, heaters, air nozzles, etc. The list is endless.
Quite often simple inexpensive fixes like fitting solenoid valves to automatically shut components off when not required can save a considerable amount of energy.
One final area to consider is the challenging of process parameters. To change the state of a product i.e. heat, cool, compress, etc consumes energy, often a considerable amount of energy. Yet all too often there are unnecessary buffers built in “just because they have always been there.” Air might be compressed to 7 bar when 6 would have been adequate or a product might have been heated to 200 degrees when 180 would have done. Challenging the parameters can often yield significant benefits with no loss of quality or output, there just needs to be the will and drive to make it happen!
As manufacturing processes and equipment are specific to organisations, it is simply not possible to cover every opportunity in such a short article. However, it is hoped that the points raised demonstrate that opportunity is there, if you have the will and drive to go and find it!
