I agree with this entirely. Some countries managed to reduce CO2 emissions from their electricity production. However when you look at primary energy consumption, including heating, industry, transportation, no country manages to reach a low-CO2 energy profile.

> There are plenty of people in the UK who have a financial problem in keeping warm in the winter.

There are plenty of people in the UK who live in old, precarious buildings with very poor insulation. Mandatory paid-for insulation in these buildings would reduce energy consumption, CO2 emissions and increase comfort of living. That's part of the measures pushed forward by Jancovici.

> And who defines excessive?

That is, indeed the key question of our times.