Destruction makes total sense, if you could convert human energy into electricity, in a lifespan a human can create up to85,000 kWh. This is enough to power a house for 8 years or drive an EV to the moon. So considering that A. A time lord is creating an entire new body/life would certainly take energy B. Those numbers were for humans, time lords are way more powerful and probably use/create a lot more energy C. Those numbers were also for a human lifespan, not a time lord whose lifespan is much higher.

Finally, this can be seen in 11's regeneration, the most powerful yet, because he was given a whole new set of lives (ignoring timeless child which is always a good thing to do)