There is a wealth of expertise and evidence on what is a sensible path for decarbonisation of heat in the UK. Having worked on multiple biogas projects and having worked on this issue for over a decade, this idea that we can use biogas at scale for heat can be dismissed (thread)
1. Availability of bio-resource. Huge amounts of land would be needed. There is recognition of some (most) meat grazing land being re-purposed. But more fundamentally, this would be a restructuring of much of agricultural system.
For context, the @theCCCuk, who have done the most detailed analysis around this issue suggest that the use of bio-energy in heating should DECREASE by 2050 theccc.org.uk/wp-content/upl…
2. Sustainability. Purpose grown energy crops are not (near) zero carbon. Inorganic fertiliser tends to be used but even in organic systems, the energy used in the process and methane leakage can be significant. Current standards are not near zero carbon: ore.exeter.ac.uk/repository/han…
Of course wider sustainability concerns over monoculture are important too. I note the farmer interviewed in the original piece is not just farming 'grass', it was maize and cereal too.
3. Costs. Ignoring wider system costs (will come back to this), biogas is expensive. Beyond the capital cost of the digestors, there is the actual cost of the growing of the feedstock, harvesting it, running the digester, and upgrading it to put it in the grid.
Before the non-dom RHI closed, biomethane was being offered support which effectively meant a unit of biomethane cost way more than double wholesale gas. And this was through intense, high output faming methods, not grassland.
As far as I can tell from the web page, these operational and feedstock costs haven't been considered and a £700 a year gas bill is used, basically, a normal bill. This is wrong.
Lots of issues are also ignored. How is this gas stored interseasonally? An issue with biogas projects is that they are normally designed for the minimum summer day, so basically huge amounts of gas storage would be needed.
Biodiversity: ignored
Residual emissions: ignored
The fact that there is a wider energy and agricultural system: ignored
Costs beyond digesters: ignored
Purposefully poor heat pump efficiencies are also used. The lowest daily COP I have had for the past 12 months is 2.7
Now I've said repeatedly, we need to have a national conversation about heat (among many other things) blogs.exeter.ac.uk/energy/2019/08…. But also, that this needs to be based around evidence and it needs to be independent of interests.
And I fundamentally see this intervention around biogas as an unhelpful distraction which is wasting time, when there is no time to waste.
Whole system analysis is needed which considers developments elsewhere in the energy system, storage and capacity requirements, interaction with transport and generation sectors. And this has already been done, repeatedly. By @UKERCHQ, by @theCCCuk, by @beisgovuk etc
As far as I am concerned, we should be getting on with delivering known low carbon solutions, heat pumps, heat networks and energy efficiency, rapidly and at the scale as pointed out by the CCC. theccc.org.uk/publication/si…
And furthermore, to ignore the potential of offshore wind to provide the bulk of our heating needs, sustainably and cost effectively, would be criminal. heatgeek.com/the-answer-to-…
• • •
Missing some Tweet in this thread? You can try to
force a refresh
Fundamentally, heat pumps are expected to be central to the global energy transition (see @IEA, @HeatRoadmapEU, @beisgovuk, @theCCCuk, @UKERCHQ). The UK's large heating appliance manufacturing base could pivot into this strategically important tech.
@KensaHeatPumps and @Ecodanheating already provide heat pumps to the UK market, but the majority are imported. @vaillantuk are currently setting up a manufacturing line for their own air source units in Belper. But more investment is needed to fully realise the opportunity.
The UK hydrogen strategy outlined the government's support for a 'twin track' approach which supports both 'green' (from renewable electricity) and 'blue' (from fossil gas) hydrogen. This has caused a bit of stir, so what are the issues? (thread).
So firstly, why blue? Well it appears to be linked to a corporate strategy, and it appears to have stuck!
So what is it? Well 'blue' hydrogen is produced from fossil gas in a process in which the resulting carbon is captured and stored (i.e. it's Carbon Capture and Storage, CCS). The stored carbon is not expected to reach the atmosphere so has no climate impact.
Heating: what does the hydrogen strategy say? In short, it's all about trials for the next decade but delaying action on heat pumps and heat networks 'could prevent us from meeting near term carbon budgets' (thread).
First up, some confusion about how many homes will actually be heated by hydrogen by 2030. The press release says 3 million by 2030, the actual document says something very different: (very odd).
In terms of volumes, by 2030 growth in domestic use is limited to the trial places so quite small. Note huge uncertainty over 2035 range. Basically this is 'we don't know'.
The absolutely criminal thing about heat decarbonisation/heat transition politics is the total ignorance by policy makers of the value it will bring to the UK. Ignoring the carbon reductions, it will save money and pay for itself through the reductions in gas imports (thread).
Currently GB is very reliant on fossil gas, more than almost all countries apart from the Netherlands. This is because we went big for gas in the 60s and 70s after finding North Sea gas. But that time is over. We now import over 50% of gas and that's expected to increase.
So, we import over half of our gas. In 2019 that equated to 518 terawatt hours.
I think I've now managed to digest all the Times pieces today (I was featured in one of them) and thought I should set out my stall in a short thread. So, last week The Times featured an 'opinion piece' suggesting No 10 were very interested in hydrogen:
I was interviewed following the submission of a letter to the editor, not from me, but from another academic. csrf.ac.uk/2020/09/letter…. A shortened version of this letter featured today.
Focusing on the issue of incumbency, we investigate the emergence of a low carbon gas coalition in the UK. We investigate what the coalition has been doing and the messages it has been promoting primarily through political lobbying and policy engagement.
Converting the gas grid to low carbon gas is presented as *the* option for heat decarbonisation in areas with a gas grid at the expense of other options such as heat networks and heat pumps.