This is why we created Lun. Every gas boiler's consumption emits about 2tCO2 per year - and there are about 90 million buildings in Europe that could be heated using heat pumps instead, with huge benefits for energy efficiency and carbon emissions.
As you said, it's a hard problem.
Luckily, politicians and bureaucrats are passing more and more legislation that will force the fossil fuels out of heating over the next decade. We see it as our job to make sure it's going to happen in real life by being the glue between all parties in the value chain (consumers, OEMs, installers, utilities, governments, financial institutions).
And we're looking for great people ;) careers.lun.energy
We're also super proud that the data is being used by Google to ensure that they use their data centers more when the electricity is greener and to help them in goal to make their electricity usage 24/7 carbon free in 2030 (https://www.gstatic.com/gumdrop/sustainability/247-carbon-fr...)
Alright, I got criticized for spamming on other climate change posts for copy-pasting links, so here's what I'm doing.
My background is growth/marketing, having worked at startups, Uber and Google. I'm quitting Google end of summer to work on climate change full-time, but right now I'm helping out 2 tech communities [1][2] and one startup working with open-source projects, calculating people's CO2 emissions in a privacy-by-design manner[3].
After the summer, I hope to join that startup full-time (if they want me ;-) ) and help also in politics with the Citizen's Climate Lobby[4] and their effort to pass a Carbon Fee and Dividend legislation globally.
Even if you don't work full-time on it, there are plenty of ways you can help.
I'm (obviously) very involved in climate change and how tech (very represented in the HN community) can play a role in fixing it: many are asking themselves the question on how they can do something about it.
I want to help these people find a spot where they can find like-minded people interested on working on it - and I believe climate change posts on HN are a good match between people concerned about the climate, and who would be interested in joining tech communities working to fix it. I'm all ears to find other ways to give people avenues to work on their "climate" anxiety - let me know if you have better ideas.