That nice Mr Sunak has an electricity and carbon footprint way higher than the citizens that he lords over - for heating the new swimming pool of his private residence, a new connection to the national grid had to be installed across open fields. And of course he has a weakness for helicopters, usually for quick short visits for photo opportunities.
Now, he could, if he chose to, avail of such a demand based contract - sign up for one that keeps the pool at the optimum temperature all year round, but then sell back the electricity for when neither he nor family are in residence, when the thermostat can be set lower. That would of course be the financial wizz kind of thing that his instincts would say he should do, but in terms of politics and the optics, very difficult to justify - at least until he has given up politics