Source of Energy
If energy can neither be created nor destroyed, we should have no worries! We should be able to perform endless activities without thinking about energy resources then why we speak to save energy ?
Its because energy from the usable form, is dissipated to the surroundings in less usable forms. Hence, any source of energy we use, to do work, is consumed and cannot be used again.
Good Source of Energy
⇒ A good source of energy would be one
⇒ Which would do a large amount of work per unit volume or mass,
⇒ Be easily accessible,
⇒ Be easy to store and transport, and
⇒ Economical.
Renewable and Non- renewable Resources
Natural resources can be classified into the renewable resources and non-renewable resources.
The resources which have the capacity or ability to reproduce or renew quickly are called renewable resources. They include solar and wind energy, water, soil, forests, etc. Some of the renewable resources can be destroyed due to careless use.
The non-renewable resources are limited in reserves and it may take thousands of years to renew them. For example, coal or petroleum if taken out completely, may take millions of years to produce them.