

I meant up relative to the boiling point. Since the boiling point is lower, the same heat output is relatively higher. It just boils the water faster and does nothing to the temperature. You just need enough heat to get it to a boil if you don’t want to waste extra water and heat.
But it does change how much power you need to use. If you leave the power the same, you’ll need more joules because you need more time and are sending more of it to the atmosphere.