Fossial fuels and alternative souces of energy

Fossil fuels (coal, oil, natural gas) are the main sources in many countries, but in some countries the use of alternative sources of energy (wind energy and solar energy) are encouraged. To what extent do you think it is a positive or negative development? 

It is irrefutable that fossil fuels are the main source of energy in many parts of the world, but some nations are taking a step forward and using renewable sources like wind, solar and tidal energy. Definitely, it is a positive development. In the following paragraphs I intend to support my views with my arguments. 

The main advantage of using alternate sources is that the conventional sources like coal and oil are non-renewable. They take millions of years to make and we are finishing them at an alarming rate. This means that if we finish the existing resources they will be gone forever as far as our and the coming many generations are concerned. Energy from the wind, the sun and the sea is an everlasting source of power. So, more and more governments should come forward in promoting these sources. 
Another big advantage of these non-conventional sources is that they do not pollute the environment. We all know that global warming and damage to the protective ozone layer are caused by carbon-dioxide and other by-products of fossil fuels. If urgent steps are not taken towards the use of natural sources like sun and wind, then the time is not far when the whole earth will transform into a boiling pot.  

Although the use of these alternative sources has some hurdles such as the initial cost of setting up solar panels and wind farms is very high and these are also dependent on the geographical locations. However, once the initial cost has been met with, their maintenance is practically negligible.  

To put it in a nutshell, I pen down saying that the use of these alternative sources is a very positive development. It should be the global priority to invest in such research and development.