When energy-saving hots up
It’s easy to talk about preventative maintenance as an effective means of saving energy, but it’s harder to put it into practice. After all, identifying where maintenance is required can often be difficult or impossible until the problem has developed: by which time the damage is done, the losses have mounted and it’s no longer preventative maintenance you are undertaking, but reactive repair. However, thermography and ultrasonic air leak detection can offer a solution that’s relatively inexpensive, non-intrusive, and can quickly pay back your investment, many times over.
You might expect your HVAC systems or steam circuits, for example, to emit heat. But you may not have realised that every object – hot or cold – emits energy, which can be detected by a skilled operator using a thermographic camera. So even an electrical circuit – which could be eating up your energy costs through a fault, bad design or improper use – can be effectively surveyed with thermography, and its problems readily identified, before the fault becomes major and the losses catastrophic.
How catastrophic? An energy and heat loss survey carried out by ERIKS at Pirelli’s manufacturing plant in Carlisle has resulted in energy savings estimated to be in excess of £60,000, yet the survey cost less than £1,500 to complete. So obviously, preventive maintenance and energy-saving through the use of thermography is not just a lot of hot air.
Wherever areas of heat and energy wastage may be occurring on your site, a thermographic survey can quickly identify them – whether they arise from central heating or refrigerators, or from subtle aspects of building and plant design which would otherwise go unnoticed and uncorrected. A survey can also be carried out quickly and unobtrusively, without any disruption to the normal operation of your facility. There’s no need to turn off equipment (in fact the survey is most effective when plant is running) and as the thermography camera works just as well at a distance from the problem, there’s also little or no need for temporary access via scaffolding or ladders.
A typical survey might cover your motors, pumps, fans and their control panels. It would also look at control equipment, cable runs, substations and transformers, as well as thyristor banks, switches, fuses, circuit breakers and distribution boards. in addition, the survey would look at the exterior of your buildings, to identify heat loss problems through poor insulation, draughts, or over-ventilation. An examination of hot water systems and steam circuits will also often identify heat losses, which in the case of badly insulated pipes can reduce thermal efficiency of the overall delivery system by as much as 50%.
in one survey carried out by ERIKS, for example, a steam supply pipe which had been left uninsulated after maintenance (as the process of replacing the insulation would have disrupted production) was shown to be causing estimated losses of £2,600 per year: a high price to pay every year to avoid a small one-off amount of production downtime.
Thermography is ideal for identifying these kind of losses which, due to the inaccessibility of the places they occur, would otherwise go unnoticed – except on the bottom line. A failed steam trap is a good example, as this can cause losses running into hundreds of pounds, or even thousands, every year. A simple survey with a thermal imaging camera will help you to understand and compare the condition of your steam traps, identify any problems, and help you to target preventive maintenance when and where it’s required. Similarly, electrical circuit faults or poor design will often go unnoticed until it’s too late and an expensive repair is required. However, because a faulty or unbalanced circuit produces unusual amounts of heat in places that can be detected and analysed thermographically, it’s easy to diagnose the problem – from corroded connections to poor ventilation or circuit overload – and take preventive action.
The typical survey takes around two days to complete, and in this time an experienced operator with a thermography camera can cover all the areas where energy loss may be an issue. A recent survey at the Coors Brewery in Burton-upon-Trent, for example, took just two days, yet encompassed boiler houses, overhead pipework, tank houses, the brew house, powder rooms and outside areas across the site. The result was a comprehensive report which identified potential savings of around £60,000, ranging from £288 per annum for a minor energy loss to up to £21,000 per annum for energy losses from outside pipework.
A useful adjunct to a thermographic survey is an air leak survey, using the latest ultrasonic leak detection technology. Again this can be undertaken without disrupting the normal operations of your plant, yet can result in some impressive savings.
A survey for Cavaghan & Gray – a leading supplier of own-label chilled ready meals – led to the identification of problems in the compressed air installation at its factory, preventive maintenance of which has now directly resulted in savings of £86,000 per annum.
As Mark Eagling of ERIKS points out, “With savings of £86,000 per year achieved, it might sound as if the compressed air installation in the factory was in poor condition, but the results are in fact fairly typical for a regularly maintained installation of this size. There are many other companies that, by spending just two or three thousand pounds on a similar survey and appropriate remedial work, could make savings equally as big, if not bigger.”
With such savings as an incentive, it might even seem economical to invest in your own thermal imaging equipment. However, the benefits of having a highly-trained and experienced operator behind the camera cannot be over-emphasised, which is why many people chose to outsource their surveys to a third party such as ERIKS. Whichever route you take, you can confidently expect to detect energy losses which have previously gone unnoticed, giving you the information you need for effective preventive maintenance, and the basis for quick payback, reduced energy loss, greater energy-efficiency and lower energy costs.