The Government’s announcement that from 2025 gas boilers will have to be ‘hydrogen ready’ could presage the start of one of the greatest pieces of greenwash that have been committed in the UK. It seems likely to result in carbon emissions being substantially increased compared to the present use of natural gas in boilers to heat homes. The oil and gas industry is promoting so-called ‘blue hydrogen’, that is hydrogen produced by ‘reforming’ natural gas, and capturing the carbon dioxide that is produced. Yet currently most hydrogen is produced by reforming natural gas and not capturing carbon dioxide, a process that will dramatically increase carbon dioxide emissions if hydrogen is used to heat homes. The efficiency of the gas reformation process is only around 65 per cent meaning that much more carbon dioxide is generated to produce the hydrogen as fuel compared to simply burning the natural gas. Any claims that the process will be done using carbon capture and storage, beyond that is a few demonstration projects supported by public grants, should be taken with a wagon load of salt. But the sad thing is that even if ‘green’ hydrogen for heating homes was to be generated by renewable energy (through electrolysis of water) it would still be a grossly inefficient way of using that renewable energy. Renewable energy is normally distributed through the electricity system where it can power heat pumps in homes (either individually or through district heating systems) to much much greater effect. The heat pumps use electricity much more efficiently compared to any hydrogen boilers, no matter how the hydrogen is produced. Indeed a heat pump may increase the efficiency of the use of renewable energy by approaching fourfold compared to using ‘green hydrogen’ in a boiler. Not only does the heat pump multiply the heat from the electircity by around threefold (by using heat in the surrounding environment) but it avoids losing energy through electrolysis, So, in terms of reducing carbon emissions we will need FOUR times the amout of renewable energy to produce the same heating effect in buildings if we turn it into hydrogen – compared to using the renewable energy delivered through the electricity system and used in heat pumps. So the Government should be looking at ways to ensure heat pumps are used as a rule in new buildings and giving incentives to have existing buildings retrofitted with heat pumps. This is as opposed to being hijacked by the oil and gas lobby to pass off business as usual under a greenwashed cover story.
Dave Toke’s Blog 4th Jan 2020 read more »