The SI system has the Joule for that. The real "problem" is that 1 Joule of energy is just too small to be practical in most situations, so we often resort to l

The SI system has the Joule for that. The real "problem" is that 1 Joule of energy is just too small to be practical in most situations, so we often resort to larger units such as a kWh (equal to 3.6 MJ).