Coal is said to be formed from the wood of trees. Why then is coal consideredto be a non-renewable source of energy whereas wood is a renewable source of energy? Answer:

Coal is considered to be a non-renewable source of energy while wood is considered to be a renewable source of energy because the accumulation of coal takes longer period than growing tress. Therefore, using coal at a very high rate will result in exhaustion of coal and therefore, it is considered to non-renewable source of energy.