One objective — many options
Photovoltaic panels, thermal storage, waste heat from machines. There are plenty of options for managing energy intelligently in production operations. Alois Müller GmbH shows us how to do it.
A big photovoltaic system, massive heat storage capacity in the floor, and bright LEDs on the ceiling. When you walk into the buildings at Alois Müller GmbH in Ungerhausen, in Germany’s Allgäu region, it becomes immediately clear: These folks take energy efficiency seriously. The photovoltaic system, with its surface area of 2,800 square meters, produces the electricity which the company uses to run its production machines, compress air, and control the climate in the factory. A special concrete floor slab stores surplus energy.
A holistic concept
It is no accident that Alois Müller GmbH decided to go for energy-efficient manufacturing. The company itself specializes both in plant and equipment construction and in energy and building technology. “To an ever increasing extent, our customers are focusing their attention on their energy consumption. When doing so, they often prefer to invest in small or partial projects. They upgrade a heater here or replace a fan there,” explains Plant Manager Jan-Peter Höhne. “In our case, we had been thinking about setting up a production facility that is fully oriented on saving energy.”
The enterprise profits from this in two ways. Not only does this keep costs down. The manufacturing plant also serves as an exhibit for its own customers. “As equipment builders in southern Germany, we see a unique chance to carry out the development and production of cutting-edge components in the field of heat and electrical supply,” adds Andreas Müller, CEO of Alois Müller GmbH.
Storage in concrete
Like all the machines in the plant, a TruLaser 5030 is also powered by the photovoltaic unit. The 380 MWh/year are sufficient to heat and cool the plant and even to provide compressed air, nitrogen for the laser cutting device, and the deionized water needed to refill the heating systems.
Over and above that, heat is stored in the floor. This is where 8,000 meters of thin heat exchanger pipes, filled with water, are arranged in several layers and encased in a 1,000 square meter floor slab. Excess energy is used to heat the water and thus the concrete floor up to 40 or 50 degrees. If the sun fails to make an appearance, Müller Produktions GmbH utilizes the energy in storage.
“We also want our own operations to use 100 per cent of the energy we produce. We meter our consumption in real time so that we can continuously improve it,” says Höhne. The target: Detailed information should be available for every component made — both production time and energy use. This makes it possible to plan consumption and synchronize it with the energy being generated.
Gathering this data is a pioneering effort, which is why the company cooperates with the Technical University of Munich and the Fraunhofer Society in questions of process monitoring. “We want to prove that certain investments are worthwhile and to launch a multiplier effect. Especially in small and medium-sized companies, there continues to be great potential for enhancing energy efficiency,” says Höhne, thinking about his own customers.
In the future, Müller Produktions GmbH will be making use of additional energy reserves in their Ungerhausen manufacturing facility by implementing TRUMPF’s universal cooling interface. It was recently fitted to the laser machine and will transfer to the factory’s climate control system the waste heat generated during the laser cutting operation.
Contact us: MastersofSheetMetal@trumpf.com
This article was first published in autumn 2013.