Operational energy management is becoming increasingly important
Profits and savings go hand in hand
Energy costs, energy transition, energy efficiency – just a small selection of keywords relating to increasingly important energy issues that we have constantly faced in the recent past. Almost all home appliances are advertised with labels showing their energy efficiency class, because even in private homes, the economical use of energy has a noticeable effect on the household budget. Therefore, how much higher is the savings potential for industries where energy consumption is much higher than in individual households and where energy costs are a major calculation factor for production?
Both areas – private households and industry – are important for the efficient use of energy. Energy efficiency has become an issue in all areas of society. Universities offer courses which are exclusively dedicated to the energy industry and energy management. In other disciplines, such as mechanical engineering, the „energy efficiency“ issue is essential in the training of engineers.
Over the past few years, nationwide networks have formed over this issue. The Chamber of Industry and Commerce (IHK) and the Chamber of Crafts offer their members comprehensive consulting services on energy efficiency in the workplace. For example, there have been large campaigns to promote energy efficiency in industry and private households, including the ‚energy efficiency initiative‘ (www.initiative-energieeffizienz.de) by the Germany Energy Agency (dena GmbH) and the ‚energy efficiency export initiative‘ (www.efficiency-from-germany.info) by the Federal Ministry of Economics and Technology (BMWi).
Many businesses are now discovering the economical use of energy for themselves. This can positively impact on the economic efficiency of a business. With concrete savings, due to implementing energy-saving measures in business, unexpected savings potentials can often be realised. Since the beginning of 2013, according to the „General Administrative Regulation for procuring energy-efficient products and services“ (AVV EnEff), energy efficiency is a required selection criterion for bidders in tenders. Energy efficiency has clearly grown beyond the stage of a mere act of conviction and into a tangible business or profitability factor.
It is not often easy for companies to achieve energy savings in their business. To achieve savings by using modern technologies, initial investments need to be made. This is not usually a problem as these investments pay for themselves in the course of time due to savings in operation and an improved competitiveness. Often enough, amortisation periods are surprisingly short.
The bigger problem in many places is that the range of modern production plants able to take energy efficiency into account is sometimes very small or even non-existent. This is very surprising when you see how high the saving potentials are for plants that implement energy efficiency measures. So you’d think a market for such technologies would exist.
One company which is committed to sustainability and efficiency, with their ‚Save the Future‘ concept, is Rehm Thermal Systems GmbH in Blaubeuren near Ulm. Since 1990, Rehm have produced soldering machines and more for global companies in the electrical and photovoltaic industries. For years, the issue of sustainability has concerned those in power at Blaubeuren. A large solar system on the roof of the production hall documents this to the outside world. With their new development, the Vision XP+ reflow soldering machine, Rehm developers have given their clients the opportunity to realise substantial savings in relatively energy-intensive PCB production.
The greatest demand for energy in a reflow soldering machine is probably in the process chamber, the stage of production in which components are soldered to the board. In the process chamber, temperatures must be kept stable at up to 240 0C for the entire production time. The idea, which was implemented at this point, sounds simple but implementation was rather complex – a significantly improved isolation of the process chamber. The final result was impressive and worth seeing. Due to the new isolation, temperatures of only about 30 0C were measured on the exterior shell of the plant. These measures alone reflected a reduction of 12% in the balance of the total energy consumption of the plant.
A second positive aspect, almost a side effect, was the energy savings generated from the low heat dissipation of the plant to the exterior. Compared to production with conventional systems, in which you could burn yourself on the exterior shell, the air-conditioning of the production hall can be of a significantly smaller scale in production with the Vision XP+. And those who know how big the energy requirements of effective air-conditioning can be, know that significant cost reductions can be deployed.
But the targeted savings are not feasible with just the new insulation and improved separation of the heating zones in the process chamber, and modified cooling sections. The wealth of data that must be recorded and monitored in the system is so large that separate software is required in order to maintain the established parameters of a production profile, or even to measure and control the energy requirements for individual sections.
With the ‚Intelligent Software Solutions‘, developers at Rehm have created a system which can reliably control and monitor the plant. One module of this system is furnace communication and furnace control. With this module, current temperatures from different heating zones in the process chamber are reported to the system and automatically corrected by controlling the fans. During production breaks the system enters standby mode. By limiting fan frequencies in standby mode, savings of up to 18% can be achieved.
The monitoring tools of the ‚Intelligent Software Solutions‘ not only monitor and control the energy requirement, but also measure and meter out the nitrogen requirements of the plant. Rehm was the first manufacturer to carry out soldering in a nitrogen atmosphere. With nitrogen, all of the oxygen from the process chamber is displaced. Thus, the oxidation of the copper is avoided in the intense heat. Since the nitrogen comes out of the LPG tanks at a temperature of -196 0C, developers at Rehm have designed the gas flow in the system so that the lower temperatures of the gases help to save energy in the cooling sections and, on the other hand, the gas vapour can be deployed for application in the process chamber via the temperatures of the PCBs to be cooled. The ’nitrogen management‘ software option regulates gas demand.
Such complex processes can no longer be controlled manually. The only reliable method is computer-controlled monitoring and regulation. Markus Mittermair is a software developer at Rehm in Blaubeuren. He sees the way to control software in such production plants as irreversible. „The software control and monitoring of processes is increasingly important in the production of electronics.“
By optimising the plants and coordinating communication with special software control, energy consumption and noise emissions are noticeably reduced in the production facilities. A better climate in the hall with less noise means a big increase in the quality of the working environment for employees – a favourable aspect for operational health management. Reduced energy consumption and healthy employees improve the competitiveness and profitability of the business.
Reduced energy consumption will pay off more and more in the future. Based on current electricity prices, in direct comparison of the Vision XP from Rehm and the optimised Vision XP+, savings in electricity costs of 5,000 Euros per year can be realised. Projected to a cycle of 5 years for a machine, savings per machine would be 25,000 Euros – based on current electricity prices.
A Rehm Thermal Systems client has calculated the following in a calculation for an existing production line, which currently consists of the older V6 series: compared to the V6 which runs in a 24h/3 shift operation, the new acquisition of a Vision XP+ will create energy cost savings of 30,000 per year. Projected to the first 5 years, we are talking about a saving of over 150,000 Euros.
If you follow the electricity price developments of previous years, you can see a constant trend despite fluctuations in individual years. Since 2000, industrial electricity prices have increased by 150%. And you will see that production costs are reducing while the proportion of fees, such as the EEG (German Renewable Energy Act) reallocation charge, sharply increases. And, according to the Energy Roadmap 2050 the EU Commission will not change anything before 2030 – at least until then, electricity prices will continue to rise.
Energy efficiency and energy conservation are factors which cannot be ignored when considering the profitability of a company. Using these opportunities to save energy ultimately means working more economically. ‚Do something good and talk about it.‘ That is what Erich Kästner said. ‚Let your facilities save for you in terms of software control and do something good with it.‘ This could be the motto for adjusting to modern technology.