For power cable, is it copper conductor better or aluminum conductor better, there are some comparation between as following, it seems that there are more advantages of copper conductor power cable over aluminum conductor power cable. 

1. Low resistivity: the resistivity of aluminum conductor power cable is about 1.68 times higher than copper conductor power cable.

2. Good elongation: the elongation rate of copper alloy is 20-40%. Copper for electrician is above 30%,while aluminum alloy is only 18%.

3. High strength: For the allowable stress, copper is 7-28% higher than aluminum at room temperature and even much higher at high temperature.

4. Antifatigue: aluminum is more likely fractured through repeatedly bending, while copper is not. Copper is about 1.7-1.8 times higher than aluminum on elasticity index.

5. Good stability, corrosion resistance: copper conductor is antioxidant and corrosion resistant, while aluminum is not.

6. Load capacity: due to the low resistivity, the load capacity of copper conductor power cable is about 30% higher than aluminum conductor power cable under the same cross-section.

7. Low voltage Loss: due to the low resistivity, the voltage of copper conductor power cable drops under the same cross-section and current. Therefore, under the same electricity transmission distance, the voltage quality is guaranteed. Or we can say that copper conductor power cable can reach farther under permissible voltage, namely larger power supply coverage. It is advantageous for the network planning and reduces the power supply point sets.

8. Low heating temperature: under the same cross-section, the heat productivity of copper conductor power cable is less than aluminum’s so to ensure safe operating environment.

9. Low energy consumption: due to copper’s low resistivity, it is obvious that the energy consumption is lower than aluminum. It contributes to the capacity factor and environment protection.

10. Antioxidation and corrosion resistance: the connector of copper conductor power cable is stable to avoid accidents caused by oxidation. While the connector of aluminum conductor power cable is not so stable. Therefore more accidents happen at the uprising temperature when resistance increases due to the oxidation

11. Convenient installation:

Firstly, copper conductor is soft, so the permissible bending radius is small. Therefore, it is more easy to turn and pass through the pipe;

Secondly, because of the antifatigue of copper conductor, it is not likely fractured through repeatedly   bending. Therefore, it is more convenient for connection;

Thirdly, due to the high mechanical strength, copper conductor can endure more tension. This brings more convenience for installation.

The advantages of aluminum conductor over copper conductor, mainly, it is cheaper. The price of copper bar is three times of aluminum, while the specific gravity of copper is 3.3 times of aluminum. So the price of aluminum is cheaper. It is suitable for low investment engineering or temporary electricity.

12. The lightness of power cable: the weight of aluminum conductor power cable is 40% of copper’s. The transportation fee is low.

13. Antioxidation and corrosion resistance: aluminum can be oxidized into an oxidation film in the air which can prevent the further oxidation. So aluminum is a necessary material for high voltage, large cross-section, and long span aerial bundled cable.

In spite of the low price of aluminum conductor power cable, copper conductor power cable is advantageous in the power supply, especially in the underground power cable. There are many characters using copper conductor power cable in the underground such as low accident rate, corrosion resistance, high stability, convenient maintenance. This is why our country mainly use the copper conductor power cable in the underground.