Siemens’ plant in Frankfurt makes the gas-insulated, medium-voltage switchgear used all over the world – in power generation, industrial operations, wind farms, buildings, airports and even drilling on rigs – to ensure a reliable supply of power. If faults occur in distribution networks, the switchgear makes sure that networks are shut down in a matter of just milliseconds. Much like the electrical fuses used in homes, the switchgear can disconnect and reconnect whole neighborhoods from and to the power grid as quickly and easily as flipping a light switch. The switchgear is maintenance free and, thanks to the polyester powder coatings applied in the surface treatment process, it’s well protected against corrosion and the effects of ultraviolet rays.

In early 2008, the switchgear plant in Frankfurt decided to go ahead with a large-scale scale project to improve energy efficiency in surface treatment operations. For everyone taking part, it involved a lot responsibility, especially for Walter Kühn, who has a strong reputation for going the extra mile, particularly when process optimization and environmental performance are at stake. Project manager Kühn’s focus was on the long term: “When the project was launched, my dual role as head of the surface treatment unit and environmental officer meant I felt it was crucial that we looked hard at individual processes in search of ways to boost energy efficiency and to turn the findings into workable and lasting solutions.” No sooner said than done: Just a few weeks later, employees were busy exploring and refining specific solutions for the various production stages, and it wasn’t long before their efforts delivered the first quantifiable results.

One year on, all of the initiatives have been implemented as planned. Working closely with the supplier of chemicals for the pre-treatment baths used in powder coating operations, the bath temperature was reduced by 20°C, significantly reducing the amount of gas needed to heat the baths. It was much the same with the cleaning bath for the cast aluminum parts, which now is only heated to 30°C instead of 70°C. And thanks to a complete rebuild of the powder coating area’s extraction system, exhaust air is now re-circulated through filters and fed back into the hall, which means the incoming air doesn’t need to be heated during the winter months. The package of smart initiatives also included adding a heating energy-saving control system for the rooftop extractor at the spray painting station and a new centrifuge for the water used in barrel finishing (likewise converted to use an intelligent recirculation system) to cut water consumption by 95 percent and the chemicals by 90 percent. “With this enormous gain in energy efficiency, it’s fair to say this is surface treatment that’s more than just skin deep,” says Kühn with a wink.

The successes achieved by the surface treatment specialists’ energy efficiency project in Frankfurt – lower gas and chemicals consumption and no more wastewater – have set new standards from an environmental perspective. In addition, the plant has now procured a new, fully insulated pre-treatment system, a static oil separator, a sludge centrifuge and a reverse osmosis system. The department’s temperature cutting initiatives, exhaust air regulation and new centrifuge led in the first quarter of 2009 to a saving of 30.7 percent in gas consumption, or 972,352 kWh/a, compared to a year earlier. Moreover, the municipal water and wastewater volume was down 256,000 liters, and the quantity of treatment agents consumed was cut by 2,460 liters. “These reductions are helping us to meet the targets set for our location as part of the current environmental program,” explains Walter Kühn.

Using energy more efficiently translates directly into cash benefits. The switchgear plant’s reduced gas requirements alone represent an annual saving of EUR31,224, with implementation costs of zero percent, and the savings achieved by eliminating wastewater and chemicals run to EUR29,582 a year, compared to one-time costs of EUR20,886 – an investment that will pay for itself in under a year.