Re: Silver is an excellent conductor. Why don't we use silver electrical wires

The choice of a metal for wiring depends on several factors such as the 
conductivity, the cost, the strength, the weight of material needed, the 
ability to resist corrosion and sometimes the availability of a specific 
material in the form needed.  Copper is almost as good a conductor as 
silver and is much cheaper so is usually the metal of choice.  Silver is 
sometimes used in contacts and fine wires and gold,platinum and other 
more inert metals are used where good corrosion resistance is needed. 
Where weight is critical a larger aluminum wire of less weight will have 
less resistance than a smaller, heavier wire of copper or silver.  The 
materials needed for a particular job are chosen with consideration of 
many engineering requirements and material properties.
  http://en.wikipedia.org/wiki/Electrical_conductivity