How to Calculate Power Draw in a Circuit: Which Voltage and Current to Use?

Hello I'm learning the electrical circuits..  May I know how to calculate the power draw of the circuit. I know P=VI. But which voltage & current need to be considered while calculating.Attached a sample circuit.Plz help me.

 

 

You can add the power in the two LED legs of the circuit. V=100V, I=0.4397 (times 2 for the two legs), P=88W

If you wanted to, you could calculate the power for each dissipative component in the system (the resistors, leds, etc). The sum of the voltages for the resistor and the leds in a single string will be 100V and the current in each element will be the same, so the sum will end up being the same as the calculation above anyway.