Energy is expendable. Power is inherent.

If you say you don't have the power to do something, it usually implies you don't have the inherent ability (or authority) to do that.


  
  I don't have the power to lift this.
  I don't have the power to suspend you.
  


If you say you don't have the energy to do something, it implies you can't do it currently, but you may have in the past and/or you can in the future.


  
  I don't have the energy to walk another mile (but I have the power, and can walk after I've rested for a bit)
  I don't have the energy to argue with you (I'm able to, but I'm not feeling up to it)
  


Basically, no energy means you're temporarily not able. No power is more permanent.

Energy vs. Power
According to Ohm's law, V=IR (voltage equals current times resistance).

So if the voltage increases, then the current increases provided that the resistance remains constant.

I know that Voltage or potential difference means work done per unit positive charge in bringing that charge from one point to another.

So according to Ohm's law, if the work done per unit charge increases then current will increase. How can this be true? Point out my mistakes.
