We keep on hearing and reading so much about the utility of renewable energy and about the disadvantages of non-renewable energy. Yet, non-renewable options such as coal, wood, natural gas, etc. still have a number of advantages. For example, most of the world's energy requirements are still fulfilled by the non-renewable energy sources. More specifically, the countries with the highest growth rate of energy requirements, such as China and India are mostly dependent on these sources. Most of our energy infrastructures are designed on the basis of these sources and hence adoption of renewable options requires change in infrastructure. Non-renewable sources still have higher energy conversion efficiency as compared to renewable options, such as solar energy or wind energy. Hence, we are likely to be dependent on the non-renewable energy options for near future.
Hope this helps.