Question

To be saved from energy crisis firstly ......of energy should be done economically.

Answer 1

An energy crisis is any significant bottleneck in the supply of energy resources to an economy. In popular literature, it often refers to one of the energy sources used at a certain time and place, in particular those that supply national electricity grids or those used as fuel in vehicles.
Industrial development and population growth have led to a surge in the global demand for energy in recent years. In the 2000s, this new demand — together with Middle East tension, the falling value of the U.S. dollar, dwindling oil reserves, concerns over peak oil, and oil price speculation — triggered the 2000s energy crisis, which saw the price of oil reach an all-time high of $147.30 a barrel in 2008.