electric replacement for a gas boiler
According to electricityinfo.org which provides up to date info on UK generation, coal generated leccy produce about three times as much CO2 per unit generation as does CCGT generation with natural gas. Biofuel produces about a third of the CO2 emissions of CCGT and nuclear about half that of the biomass burners.
Wind, hydro and solar CO2 releases are recorded as zilch, although some would (of course) argue against this.
After the recent spate of world-wide weather-based disasters (including the two recent storms here in the UK) fewer will be speaking out against reducing the amount of CO2 released, by human activity, into the atmosphere.
Coal, for steam generation will be rather more expensive than other forms of heating but small amounts will be mined locally, or imported, for people who run model steam engines and, undoubtedly, for those full sized machines in preservation.
About 3 years ago a fully fullychargedshow video show-cased Ceres Power who demonstrated the possibility of fuel cells for household electricity generation (and heat as well).
The most relevant bit is about 7 minutes into the video **LINK**
If the gas grid were to go to higher (green) hydrogen content, that might be a future domestic development worth looking at.
More HVDC interconnectors are being added all the time and more renewable generation, too – so the grid is being reinforced at the present time. Agreed it is woeful that wind generation is often curtailed due to distribution and other problems.
So, personally, I don’t think conversions will be necessary – but for updated designs for new builds it might be a good move. I would think LPG might be the way to go for this (not a long electric lead or electrified tracks).