The cable technology route needs to set up the whole life cycle concept

In order to implement the 2025 plan, China's industrial manufacturing industry needs to establish the concept of life cycle management instead of focusing on price and neglecting quality. A few days ago, experts said that from the perspective of resource strategy, the less imported copper, the less dependent on the outside world, because copper can be recycled. With the continuous accumulation of copper imports, China has accumulated more and more copper resources, forming a huge urban mineral deposit, but the dependence on foreign imports has decreased year by year.

The State Grid Corporation's "Asset Life Cycle Management System" stipulates that "in bidding, bidding and bidding evaluation, comprehensive consideration should be given to the life cycle cost of assets, with the objective of optimizing the performance-price ratio, increasing the weight of quality evaluation elements, optimizing bidding evaluation rules, and according to the principle of strong selection and selection". According to the above principles, the core indicators of conductivity, resistivity, safety and high temperature resistance of aluminium alloy cable are lower than those of copper cable, while the cost of the whole life cycle is basically the same as that of copper cable.

According to Chen Yimin, an associate professor at Beijing Architectural University, aluminium alloys used as conductors were widely studied as alternative conductors for cables in the 1960s and 1970s due to the rapid rise in copper prices.

Aluminum alloys used as conductors are mainly AA1000 series, namely pure aluminium, AA6000 and AA8000 series conductors. AA1000 series conductors are mainly used in high-voltage overhead lines; AA6000Al-Mg-Si (Al-Mg-Si alloy) series conductors are mainly used in high-voltage overhead lines and aluminium busbar.

Both types of conductors exist as hard conductors, and joints are mainly welded. AA8000Al-Mg-Cu-Fe (Al-Mg-Cu-Fe alloy) series is a kind of soft aluminium alloy which is really used in distribution lines.

It is reported that AA8000Al-Mg-Cu-Fe (Al-Mg-Cu-Fe alloy) Series in North America is used in the field of low voltage distribution. However, in Europe, the aluminium alloy cable has not been recognized by the developed countries in Europe. The European countries basically adopt the solution of copper cable and pure aluminium cable.

At present, European countries have not adopted the technical route of aluminium alloy cable, mainly from four aspects.

First, the electrical performance of copper cable and aluminium alloy cable is compared. Copper and aluminium materials have obvious differences in electrical and mechanical properties. Aluminum alloy conductors are similar to pure aluminium in conductivity and resistivity, so only by enlarging the cross section can the electrical properties of copper cables be achieved.

That is to say, there is no substantial improvement over pure aluminium in terms of conductivity and resistivity of aluminium alloy cables, which is one of the reasons why European countries have not chosen to use aluminium alloy cables.

Second, from the perspective of energy consumption of copper cable and aluminium alloy cable. Because of the crisis awareness of energy shortage, European countries are very concerned about the energy consumption of materials. G.P. Ham-mond and C.I. Jones of the University of Bass in the United Kingdom have conducted in-depth studies on the energy consumption of different raw materials used in power grids in production and use.

The results show that the energy consumption of metal aluminium in production and use is about three times that of copper. Because aluminium and aluminium alloy cables consume more energy in production and use than copper cables, European countries do not choose to use aluminium alloy cables.

Thirdly, the impact of carbon emissions on the environment is compared. Aluminum alloy cable is obviously higher than copper cable. According to the results of carbon dioxide emissions from different raw materials used in power grids during production and use by G.P. Ham-mond and C.I. Jones of the University of Bass, UK, the carbon dioxide emissions of aluminium metal are twice that of copper.

In addition, WimBOONE of the Netherlands and AravKACKER of Germany pointed out in their article "Comparing Copper Core Cable Conductors or Aluminum Core Cable Conductors Widely from the Life Cycle Perspective", that the environmental impact (acidification potential) of aluminium alloy cables is higher than that of copper cables.

Fourth, from the point of view of life cycle cost. The price of aluminium is much lower than that of copper, which makes aluminium alloy cable have price advantage and brings profit space for cable enterprises. However, after comparing the life cycle cost of cable in European countries, it is concluded that there is no obvious advantage between aluminium alloy cable and copper cable.

Usually power cables can be used for more than 35 to 50 years. However, the investment decision of power cables is mainly based on the investment cost, which ignores the cost savings in the service life of power cables. The total cost of cable ownership (i.e. life cycle cost) should not only consider the initial cost of cable, but also the operation and maintenance cost of cable during its service life.

Therefore, the overall life cycle cost indicators include cable use cost, operation and maintenance cost, installation and use cost, power loss cost, residual value and governance cost.

If only one-time investment and purchase cost are considered, aluminium alloy cable and aluminium material will undoubtedly have great advantages, but from the life cycle cost analysis of copper-aluminium cable, the cost of copper and aluminium is almost the same, but copper cable is better than aluminium alloy cable.

Original title: The cable technology route needs to establish the concept of life cycle