Is hydrogen the answer? The future of heat
Posted by Brychan Williams on 2 August 2019 at 4:52 pm
In Part 1 of our blog series we looked at the role that heat pumps could play in the future of UK heating. To view that blog click here.
What other options are there available that can replace gas as our main source of heating as we move to a net zero carbon economy?
One potential solution could be to completely electrify heat. Whilst currently electric heating often uses conventional energy sources, as the percentage of renewable energy sources within the UK energy mix increases, the more sustainable this method of heating will become. However, it will still be costly for households to replace their gas boilers with electric central heating systems. Whilst the government could potentially offer financial incentives for households to electrify heat in the future, could there be potentially better options out there for the government?
One possible option could be hydrogen. The gas produces no carbon emissions when combusted and it is likely that the gas could safely replace natural gas in the UK grid system according to a new report from the Institution of Engineering and Technology. Bearing in mind that 85% of homes currently use natural gas to heat their homes, hydrogen could be a great replacement as it could make use of the infrastructure already in place within the majority of UK households. Boilers would not need to be replaced therefore making the switch in gas a very suitable option as it is likely to be more affordable for all consumers.
Currently one of the main barriers to households who want make their heating systems more renewable is the cost. If hydrogen fuel can simply replace gas within existing boiler systems, it is likely that thousands more households will be able to afford to switch due to there being no high installation costs.
However, hydrogen cannot be considered a renewable energy source if the gas is produced using non-renewable energy sources. The production of hydrogen is also very energy intensive which means that if the UK did decide to go down the route of replacing natural gas with hydrogen, it may need to substantially increase its energy supply.
Further, if hydrogen is produced via electrolysis, the use of water must be called into question. There are already concerns within the UK about a potential shortage of water in England within 25 years.Michael Webber who is an Associate Director at the Centre for International Energy and Environmental Policy at the University of Texas has provided the first analysis of the total water requirements of a hydrogen economy and his findings suggest that ‘this increase in water intensity could have unprecedented consequences on the natural resource and public policy.’
Can hydrogen replace natural gas therefore?
From a personal perspective, I believe that hydrogen is not the solution. We cannot call it a sustainable energy source if it means that it will intensively use up water supplies. Further, the production is very energy intensive. Would the UK be able to substantially increase energy output? There is already a concern amongst the government around meeting future energy demand, especially when almost half the UK's current nuclear capacity is to be retired by 2025.
More importantly would the UK be able to expand output without an increase in the use of fossil fuels?
It seems unlikely.
There are already questions being raised as to whether we will produce enough electricity to facilitate the increase in electric vehicles. Add hydrogen production to this, and it is unlikely that future demand will be met.
From my point of view it seems that the way forward is to electrify heat. However, significant investment needs to be made into renewable energy technologies so that the electricity generated to produce heat is clean. Only then will we be able to make heating across the UK fully sustainable.
In regards to new builds it makes sense for it to be a compulsory requirement for heat pumps to be installed. As has been explained in Part 1 they are very efficient in well insulated homes. For every unit of electricity used, 2.5-4 units of thermal energy is created. This could mean that high energy bills will become a thing of the past for those living in very energy efficient new builds.
If you have a question about anything in the above blog, please ask it in the comments section below.
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