Because if energy conservation is NOT valid, then this would be equivalent to the laws of the Universe changing over time. The details of this relationship are complicated (some advanced math); if you know a lot of math, and are interested in this topic, do some reading on Noether's Theorem. If you don't know the advanced mathematics, you can still get a general overview.
JSW Energy was created in 1994.
Agri-Energy Roundtable was created in 1980.
EDF Energy was created in 2002 when the UK branch of the French energy firm EDF acquired London Energy and Seeboard.
Sapphire Energy was created in 2007.
Sudden Burst of Energy was created in 1996.
JSW Energy was created in 1994.
How was energy created at the beginning of time? If energy cannot be created nor distroyed then how did it originate?
Agri-Energy Roundtable was created in 1980.
Houston Energy was created in 2000.
CMS Energy was created in 1890.
Star Energy was created in 1999.
Atmos Energy was created in 1983.
Energy Matters was created in 1980.
Posco Energy was created in 1969.
Country Energy was created in 2001.
Exillon Energy was created in 2009.
CPS Energy was created in 1942.