Living without fossil fuel heating.

I submitted last month's post to resilience.org, but they didn't want to publish it. Because I was not fasting for my own enjoyment, in fact, because I was freezing with three sweaters on, because I didn't want to turn on the heating in my office and thus cause climate change while trying to convince others to stop causing climate change, and because my fasting wasn't actually stopping climate change by itself, I stopped. What does mitigate climate change is that my direct carbon emissions are zero. I don't fly, don't drive, and heat my house with wood that I've cut by hand. I do occasionally take the train, and sometimes that train is diesel powered, and very rarely I take the bus or share a car/taxi, but given that I don't get to decide what fuel goes into those trips, I argue that those are part of my embodied carbon emissions. In fact, I wish that train companies would start offering green surcharges that would buy enough Renewable Obligation Certificates to run my train trips on green electricity (would add ~0.008 £/km to the ticket price).
Now OFGEM has decided that they wanted to make it easier to compare utility prices, so they've said every supplier has to have the same pricing policy, with a standing charge that you pay no matter how much or how little electricity or gas you use. Talk about perverse subsidies: if you use less than 900 kWh/y electricity or 2650 kWh/y of gas, you get to pay more. In fact I get to pay twice what I used to pay for my electricity. I thought we had agreed to limit climate change to 2°C by the end of the century, and would therefore expect people who use less than the average to be rewarded. Well, anyway, if you're living a sustainable lifestyle in a deeply unsustainable country, other people's cognitive dissonance is a daily fact of life*. So, although I have heated my house exclusively with wood for the last 4 years, it wasn't until today that I've had my gas supply cut.
It does feel different, even if there's no actual difference. Because I no longer have a backup to my electric shower, I'm thinking whether I should have a different backup installed. I'm thinking in particular of a water jacket around my flue. And/or a solar water heater, although the systems that you can buy off the shelf are so expensive that I'm worried that their embodied energy are going to be higher than what they are ever going to pay back if there's no seasonal heat storage. Anybody know what it takes to store hot water underground in summer for winter use? My searches on the internet haven't turned up anything that sounded feasible on the household level, so if it's possible please let me know.

*Mind you, I'm not saying that I'm less prone to cognitive dissonance than the next person, simply that it's less likely to be biased towards unsustainable actions.