Around the year 2000, the United States developed technologies to extract shale gas and in the last 15 years, increasing extraction of shale gas has totally transformed the energy economics in that country.
It has triggered shale gas extraction in Canada as well.
Shale gas extraction is limited almost exclusively to these two countries.
Many other countries, including India, have significant amounts of shale gas.
If we are able to extract shale gas like the US, it will go a long way in ensuring our long-term energy security requirements.