Question

 

1) What types of consideration must be made when selecting the appropriate type and style of conductor for high voltage and long distance transmission? How do thermal reaction and stress/strain propeties factor into these decision.

2) How do we acquire the metals that we used for conducting paths in our circuit? what are some impacts of these method on environment and social level?

Answer 1

1) Aluminium is used to make most of the high voltage cables. This decision is influenced by many factors:

• First and foremost the material has to be cheap and abundant in nature.
• The material should have relatively high conductivity.
• The material should be resistive against most natural forms of corrosion and oxidation.
• The material should be lightweight.
• It should be flexible against any kind of stress/strain. Most of the time there's a fixed predefined tension is already there in a high-voltage transmission line but as metals tend to stretch/shrink during thermal fluctuation the flexibility has an effect on the stability of the cable.

2) We use copper and gold to connect various components in a circuit.

Gold is a noble metal, i.e. it does not create a compound with other materials, so in nature gold is extracted in a physical way, separating gravel and sand from the gold when it is found in a mine either by hand with a separating bowl or in a machine which vibrates and washes away the gold from dirt.
Microprocessors and ICs use gold for all connections inside them. High-end electronics and Audio product often use gold wires to minimize signal loss.

However, copper is extracted from the Cuprite ore. It is obtained commonly from an open pit, then it is processed with dilute sulphuric acid to obtain copper sulfate. Then with electrolysis copper is obtained from copper sulfate.
PCBs and microelectronics are dominated by copper connections.

As the devices become faulty and obsolete most of these end in an electronics garbage-dump. Heavy metals such as copper have a negative environmental impact. Copper is essentially lethal for microorganisms that help farming and processing bio-materials in the soil. Recycling these type of electronic garbage can potentially benefit humans on an economic and environmental level.

Mining copper is essentially impactful on surrounding nature and biological system. Only a little fraction of the ore becomes copper so the rest of dusted rock and byproduct sulphates start to chemically affect the environment while being economically useless. The waste products become acidic materials, heavy trace metals start to come out as sulphate compounds and the acidic nature further accelerates the process. Getting exposed in nearby streams and underground water these chemicals contaminate the whole ecosystem and us humans.