Such unconventional gas production accounts for nearly a quarter of total production in the United States, according to the latest figures from the Energy Information Administration.

To keep its bathers from shivering and its energy bills from ballooning, the city has developed some clever ways to reuse excess heat from two unconventional sources, computer servers and sewage.

Natural gas hydrate which plays a fair role in sealing the conventional oil and gas reservoirs is a new unconventional energy resources with great potentialities.