A description of the application
Upsizing copper cables has multiple applications, including for example small and large offices, industrial areas and large industrial plants. Small and large offices typically use low voltage copper cables whereas for industrial areas and large industrial plants, which have higher power demand, it is more common to use medium voltage copper cables. The demand for copper depends on the application considered.
There are relative differences in power losses between standard cables and upsized cables, which arise from the fact that cables with larger cross-sectional area are subject to lower transmission losses.
When considering different applications, it is also important to consider collection rates and end-of-life of the cables, in order to have a holistic understanding of the systems – life cycle thinking.
The challenges that appear regarding this application
The main challenge identified in the context of the upsizing copper cables is related with the question whether the energy saving potential justifies larger cross section cable dimensioning strategies for the design of electrical cable systems. The common sense could lead to consider that the environmental impact of producing additional copper makes the use of larger cable sizes environmentally disadvantageous. Studies (see references) investigating this question have bring the facts into light.
How copper serves as a key factor to overcome this hurdle
These studies considered different environmental impact categories focusing on global warming potential and others such as acidification potential or summer smog.
Focusing only on the production phase of the cables, for most of the categories, 60% to 90% of the environmental burden has origin in the production of the copper required; the rest has mainly origin in the production of the plastic components. The exception is the summer smog (photochemical oxidant creation potential, POCP), for which 44% of the impact stems from copper production, as plastic production releases significant nitrogenous emissions, which are relevant for this category.
Considering the entire life cycle of the cables (production, use, and end-of-life), it becomes clear that within few years of use the impact from the production of the cables is overshadowed by the impacts due to energy losses during the use phase. These impacts are represented by the emissions associated with the production of the same amount of electricity.
Cables with smaller cross sections have lower starting (production) impact but greater annual energy loss rate. The upsized cables, delivering equivalent electrical function, have higher starting (production) impact but lower annual energy loss rate.
Therefore the cumulative impacts for different impact categories intersect at a certain point before which the standard cables are advantageous and after which the upsized cables become environmentally advantageous.
The key message as a conclusion
Overall, there are clear environmental advantages on using upsized copper cables. The mitigation of increased production impact by the use-phase savings is visible in the early inflexion point (often within 1 year compared to average cable lifetimes of about 30 years).
An investigation into the environmental effects of upsizing of copper cables in commercial applications. European Copper Institute, thinkstep; 2015
Modified Cable Sizing Strategies Potential Savings vs Copper Usage. European Copper Institute, Consulting NV; 2011
- Application in large offices is considered; operating hours: 60 hours of day time load per week
- EU-27 power grid mix (GaBi 6, database 2013)