Cables Standard Minimum Cross-Section: Often Not the Best Economic Choice

Related Vendors

U.I. Lapp GmbH

FAULHABER Drive Systems

Wuxi InfiMotion Technology Co., Ltd.

Thinner cables are often assumed to be more sustainable as they use less material. However, a study by Lapp reveals that cables with a larger cross-section for energy transmission lead to lower power losses in the long term, reduce greenhouse gas emissions, and thus also lower costs. The most economical solution for a given application can be calculated accordingly.

Maximilian Christians, Research Engineer Advanced Technology at Lapp, often heard the following sentence from his mentors during his training: "When connecting the motor, just use the thinnest cable—it’s cheaper and sufficient." Even then, he wondered whether less is always better. Thinner cables may be cheaper to purchase and save material, but they cause higher power losses. Wouldn’t that be more expensive in the long run? This suspicion stayed with Christians.

Save Emissions And Energy Costs Over the Lifecycle

At Lapp, the specialist for integrated solutions and branded products in cable and connection technology, he pursued this question after completing his mechanical engineering studies. As he knows today, the common assumption that thinner cables are always more cost-effective falls short. Instead, his research on sustainability revealed that cables with a larger cross-section may initially cost more due to the higher material usage required for their production but can save emissions and energy costs over their lifecycle through lower power losses.

Gallery

In a future shaped by sustainable transformation, rising energy prices and CO₂ taxes can become a crucial factor for efficient and sustainable decisions for users.

Maximilian Christians

Larger Cross-Section, Lower Power Loss

It quickly became clear that thinner cables, due to their higher electrical resistance, generate more heat and thus result in greater power losses. The thicker a cable is, the lower the resistance becomes—the current can flow unimpeded without a significant portion of the energy being converted into heat. This insight is particularly relevant for industrial applications where high currents flow, as power losses increase disproportionately with higher loads. Accordingly, cables with a larger cross-section not only save energy but also reduce the heating of the connection, contributing to higher operational safety and a longer lifespan for the entire configuration.

The initial manufacturing and acquisition costs for cables with a larger cross-section are, however, higher than for thinner cables and are initially associated with higher CO₂ emissions due to their greater resource requirements, such as copper. "The solution cannot, in this context, be: we take the thinnest cable to save money or the thickest to protect the climate," explains Maximilian Christians. "Instead, it's about calculating the optimal balance. As part of Lapp's advanced development team, I was finally able to develop a well-founded method for this."

Calculate the Best Economic And Ecological Choice

A calculation method developed by Maximilian Christians considers not only acquisition costs but also operating costs over the entire lifecycle of the cable—the so-called Total Cost of Ownership (TCO). As his studies show, the purely standard-compliant minimum cross-section is often not the most economically and ecologically optimal choice.

For example, the standard minimum cross-section for a cable length of 165 feet and a three-phase network with 16 A is 14 AWG . However, when considering long-term energy costs, an average of 10 AWG would be the more economical choice. The most sustainable solution, taking into account the CO₂ footprint over the entire lifecycle, results in an even larger cross-section of 6 AWG. Accordingly, the optimal cable cross-section depends on several factors, such as the rated current, usage duration, and power mix. "Companies should pay attention to this when selecting their cables," explains Maximilian Christians. "Even today, a well-informed decision about the optimal conductor cross-section can lead to significant savings in CO₂ emissions and costs."

Ecology And Economy Go Hand in Hand

The selection of the right cable cross-section is one of many sustainability levers at Lapp. How choosing the optimal cable cross-section can contribute to CO₂ reduction and cost efficiency was demonstrated by the company at the Hannover Fair. So far, many mechanical engineers have underestimated cable dimensioning as a lever for reducing CO₂ emissions. Maximilian Christians is confident that Lapp will generate strong interest in this topic: "It is a perfect example of how economic efficiency and climate protection can go hand in hand. The long-term reduction of energy costs also means a more sustainable use of resources."

Research Findings Integrated into A Calculator

Since sustainability must also be measurable, Lapp integrates its research findings into an emissions and TCO lifecycle calculator, which allows customers to determine the ideal cable cross-section for their requirements. Through this, the company helps its users design investments that are sustainable and aligned with environmental and economic considerations.

This concept is a building block of Lapp's comprehensive sustainability strategy, with which we continue to expand our pioneering role in the industry.

Maximilian Christians

Transparency About CO2 Emissions Throughout the Entire Production Cycle

With the publication of the Product Carbon Footprint (PCF), the specialist takes another step in this direction. The PCF provides transparency on CO₂ emissions throughout the entire production cycle—from raw material extraction to production and logistics. Engineers also continuously develop innovative, sustainable materials, such as the bio-based data cable Etherline Bio P Cat.5e or the bio-based Epic connectors, which significantly reduce the use of fossil resources. "Sustainability is embedded in Lapp's DNA—you can see it in many areas," explains Maximilian Christians. "From advanced development at the Stuttgart site to development and production, and even in our logistics, where Lapp reduces emissions with optimized shipping routes and partially recycled packaging material." Smiling, he adds, "And personally, it makes me happy to now demonstrate with data to my former mentors that the thinnest cable is not always the best choice."

Secure and Compliant Authentication in Laboratories

Secure & Contactless User Authentication at GMP/GLP