DiloSpinnbau Manufacturing Facility Reduces Annual Lighting-Related Energy Usage by 91%


Customer: DiloSpinnbau
Location: Bremen, Germany
Facility Size: 6,600 m2 (71,042 ft2)
Operational Schedule: 8 x 5
Environment: Ambient/Manufacturing
Previous Solution: T8 fluorescent luminaires
Installation: Retrofit
Cost Savings: €72,000/ $94,000 (at 1.32 $/€) annual
Energy Savings: 91%

DiloSpinnbau Manufacturing Facility Replaces T8 Fluorescent Lighting with Intelligent LEDs, Reducing Lighting-Related Energy Usage by 91% Annually

Located in Bremen, Germany, DiloSpinnbau is the world’s premier manufacturer of universal and high-capacity carding machines used to process nonwoven fibers. For more than 50 years, DiloSpinnbau’s carding machines have been used in applications that range from textile and leather manufacturing, to cosmetics, medicine and hygiene. The company maintains a 6,600-square-meter (71,042-square-foot) manufacturing facility in Bremen and through its parent company, the DiloGroup, markets its products in more than 80 countries.

At DiloSpinnbau, energy efficiency and sustainability are top priorities, fueled by high energy costs and Germany’s 20-year commitment to becoming a nuclear-free nation. At €0.20 (or $0.26 USD) per kWh and rising approximately 10% annually, this spurred the management team at DiloSpinnbau to conduct a thorough review of how energy was being used within its Bremen facility. To their surprise, they determined that lighting consumed startling amounts of energy, and that one of the easiest, highest return investments they could make to save energy was to upgrade facility lighting.

Intelligent LED Lighting Alters ROI Equation

Convinced that LEDs represented the future for industrial lighting, DiloSpinnbau began a multi-year search for a replacement solution for its T8 fluorescent luminaires. Following the in-house testing of a range of LED alternatives, the management team remained unconvinced by the incremental energy savings and long payback periods associated with these solutions. That all changed when lighting experts at SchahlLED, a national LED lighting design and distribution firm, recommended the Intelligent LED Lighting System from Digital Lumens.

Unlike the basic LEDs DiloSpinnbau had previously tested, the Intelligent Lighting System met the team’s vision of a highly controllable, “smart” lighting solution that would enable them to improve facility lighting while accruing massive energy savings. In fact, by replacing its T8 luminaires with the Digital Lumens system, the Bremen facility:

  • Reduced its energy usage by 91% annually
  • Saved more than €72,000/$94,000 (at 1.32 $/€) in annual energy and maintenance costs
  • Reduced CO2 emissions by more than 220,000 kilos (220 tons) annually
  • Increased illumination levels by 250 lux (23 footcandles) or more
  • Secured a payback of 1.7 years without the aid of rebates or incentives


“In side-by-side comparisons, Digital Lumens’ Intelligent LED Lighting System significantly outperformed fluorescent and basic LED alternatives in lighting quality, delivery and energy savings, making it the first LED solution we’ve seen with the investment returns necessary to justify the switch from fluorescents to LEDs,” said Erich Obermeier of SchahlLED. “For a company like DiloSpinnbau, where lighting plays such a major role in its day-to-day operations, it has transformed facility lighting into a flexible, manageable asset and a major source of energy savings.”

Even though the Bremen facility operates on an 8-hour work schedule, five days a week — compressing the amount of time available to accrue workday energy savings — the Digital Lumens system had an investment payback period of 1.7 years. As importantly, the DiloSpinnbau management team locked in annual savings in excess of €72,661 ($94,000) for the entire lifetime of the lighting installation, which at current usage rates equates to more than €363,000 ($476,873) in savings over 5 years.

Daylight Harvesting Delivers Big Savings

The Bremen facility is comprised four major workspaces —a manufacturing area for the carding machines, an assembly room for building control panels, a storage area, and shipping room — each with different lighting needs. In most workspaces, skylights, 45-degree angled windows in the facility’s gambrel-style roof and side windows, provide ample amounts of sunlight during daylight operating hours.

With integrated daylight sensors built into every lighting luminaire, the Intelligent Lighting System is enabling DiloSpinnbau to leverage ambient light to reduce its overall lighting energy use by 35%, significantly contributing to savings. The luminaires continuously assess the amount of available natural light — which varies luminaire-by-luminaire as you move away from the light source — and smoothly dim or turn off each luminaire, while ensuring that target lux levels are met.

In the largest floor space, which 5 assembly — each measuring approximately 10 meters wide by 100 meters long (approx. 33’ x 328’) — there is often so much natural light available that it has created a unique problem: How do you demonstrate lighting to interested third-parties if it is so dim as to be nearly undetectable? The Intelligent Lighting System’s ability to create, save and use different lighting profiles solved this problem by creating a profile setting that, when activated, turns the lighting to full ON over one of the five assembly lines for a 10-minute demonstration period.

Fine-Tuning Lighting to Meet Task-Specific Needs

Increasing the quantity and quality of lighting to facilitate a variety of production activities — from the reading of mechanical diagrams to the assembly of carding machine control panels comprised of many small cables and parts — was a priority for the Bremen facility. Lighting needed to meet or exceed minimum lux requirements and, once that threshold had been met, optimized to deliver just the right amount of light needed to complete specific operational tasks.

“Just as the tasks vary, so too do the lighting needs associated with those tasks,” said Dr. Hartmut Freund, Technical Director at DiloSpinnbau. “With fluorescents, this typically means over-lighting large areas in order to get enough light to critical work surfaces, resulting in high energy usage and glare. It’s a very inefficient way to deliver lighting. As we’ve proven with the Digital Lumens installation at DiloSpinnbau, the ability to control lighting results in better lighting practices and more targeted delivery, with real impacts on product quality, profitability and energy savings.”

Unlike the T8 fluorescent luminaires it replaced, the Intelligent Lighting System nearly doubled the amount of light reaching critical work surfaces, from 150-200 lux to more than 450 lux within the production area, while also meeting the control panel assembly area target of 1000 lux. Other major benefits of the new system include the ability to:

  • Independently aim each of three light bars within every luminaire. This enables lighting to be directed to where it needs to go, eliminating the need to over-light spaces — a primary source of glare — or use reflectors.
  • Fine-tune dimming settings to optimize lighting. This has resulted in more than 20 task-specific zones within the production area, each with different lighting scenarios. As a result, welders no longer complain about too much light reflecting off work surfaces and, alternatively, control panel assembly workers gain the intense lighting they need to complete intricate tasks.
  • Automatically dim lighting when a space is unoccupied. Integrated occupancy sensors automatically dim lighting to 15% when a space is unoccupied for a specified period of time, such as during the company’s twice daily shift breaks, in less frequently used areas of the facility, or during evening and weekend hours.
  • Centralized control over luminaire settings and behaviors. The ability to easily manage dimming and timeout settings — by luminaire, cell or facility-wide — without ever having to touch a luminaire or deploy a scissor lift. This enables facility engineers to continuously fine-tune system behaviors until optimum settings were reached and, moving forward, will allow them to alter settings as operational needs change.
  • Gain insights into how lighting is used via built-in intelligence. Unlike past solutions, the management at the Bremen facility now has access to comprehensive data on how lighting is being used within its facility, such as kWh used, occupancy, and usage rates. The result is better, more informed decision making on how to deploy lighting resources to increase safety and productivity, while reducing energy costs.


“In hindsight, it is amazing how easily we transitioned from being passive lighting consumers, to actively managing our lighting in a way that improves delivery and saves enormous amounts of energy,” continued Dr. Freund at DiloSpinnbau. “The results have validated our decision to not upgrade our fluorescent lighting until we found the approach we were looking for — an intelligent, controllable LED lighting system with a payback that made business sense. We found that system with the Intelligent Lighting System from Digital Lumens.”

Obermeier concluded, “Before we began offering the Digital Lumens system, we always presented our customers with two options — a basic LED solution and a fluorescent alternative — for facility lighting upgrades. The fluorescents always won. Now that we offer the Digital Lumens Intelligent LED Lighting System, intelligent LEDs are rapidly becoming the solution of choice based on rapid payback and energy savings. It’s a winning strategy for facilities focused on energy efficiency, light quality and safety.”