Decarbonising domestic heating

There’s a… not quiet, but also not mainstream, debate raging at the moment, about how we’re going to heat our homes in the future. Actually it’s about how people who live on the gas grid will heat their homes, but that is the majority, and it includes most journalists.

An important caveat

I’m not an expert here – if I was, I would be writing a journal article rather than blathering on my blog – and I haven’t done the maths. I welcome correction by people who have.

From 2035 (earlier for new builds) people won’t be allowed to install new natural gas boilers in homes in the UK. There are a few possible ways of replacing them.

One approach, as with most things, is “electrify it, then use low carbon electricity”. In the case of the UK the answer to this is electric heat pumps, which are basically air conditioners run in reverse, to move heat from outside the house to inside it. They’re more common on the continent than here, but they’re reasonably common here in commercial premises and are becoming better known as a domestic option. Heat pumps are stupendously efficient[1], doing between 2.5 and 4 times better than a basic electric heater.

There are some disadvantages to heat pumps: firstly, that they’re not a direct drop-in replacement for a boiler. You need to find somewhere to put the unit that goes on the outside of the building, and because they don’t deliver water at such a high temperature as a boiler, poorly-insulated houses will need to be insulated better. In some cases they may need to have larger radiators fitted. The UK has a lot of poorly-insulated houses, although many would argue that insulating them better is one of the first things we should be doing anyway… Another difficulty is that we’ll need more low carbon electricity to power all these heat pumps, and we might need some grid reinforcements to deliver that power to where it needs to be.

The other approach that’s being talked about is using hydrogen, produced using electrolysis with renewable electricity. Replace gas boilers with hydrogen boilers – at worst a drop-in replacement, at best a simple adjustment – run hydrogen through the old gas pipes, and bingo, low carbon heating without much cost or disruption, and because we’re still sending the energy via the gas grid there’s no need for electricity grid reinforcement.

There are a couple of downsides to this plan. One is that it’s much, much, less efficient. The total amount of energy needed to produce the hydrogen and transport it is (very roughly) 4x the amount you’d use in a heat pump that was doing the same job.

Image: ICCT

The second problem is that renewable energy is a scarce resource. We’ll struggle enough to find enough to power all those heat pumps in the short or medium term, so we’ll struggle even more to find four times that much to electrolyse all that water into hydrogen.

And this is where it gets controversial. Instead of finding enough renewable electricity to produce hydrogen by electrolysis (so-called “green hydrogen”), we could make it from natural gas. The “blue hydrogen” concept is to continue extracting natural gas, and split it into carbon and hydrogen when it gets ashore. Put the hydrogen into the gas grid, and bury the carbon back under the North Sea using carbon capture and storage (CCS). It’s quick, relatively cheap, and uses existing infrastructure. It’s not forever, of course, because both natural gas and carbon sequestration space are finite resources, but it’ll tide us over until we can produce enough green hydrogen. Right?

The strongest proponents of this plan are, unsurprisingly, the natural gas industry (fascinating scholarly report from UKERC). The next strongest are politicans who have good relations with the natural gas industry, and would like to minimise disruption. There’s a lot of lobbying power there, and this is a tempting proposition. Some people look at this and say “it’s a way for the natural gas industry to keep going with business as usual, and lock us in to a whole new gas infrastructure in the process”. Blue hydrogen champions say “but what choice is there? You can’t build renewables fast enough otherwise”. They’re usually using a straw man of building renewables fast enough for green hydrogen, rather than simply electrification, but they might be right about that too – I’m no expert on build-out rates and supply chain limitations.

But if they’re right, and if they’re speaking in good faith, then surely there’s a way to get the same stopgap benefit as blue hydrogen without locking us into the hydrogen route in the long term? Use natural gas, and use CCS, just like with blue hydrogen – but when the gas comes ashore, don’t make hydrogen with it. Burn it in a CCGT power plant, with carbon capture, and then supply electricity. Sure, you lose 2/3 of the energy in the power station, but the efficiency gains in using heat pumps rather than boilers roughly cancel that out. In the future it’s easy to let renewables replace the CCGT+CCS, at which point we’re left with a much more efficient system. And in the short term the gas companies get to keep extracting – but without locking us in for the long haul.

I don’t see anybody recommending that. Maybe it’s because it still leaves the supply chain “problem” (people will argue problem vs opportunity), in how quickly we can get homes converted to heat pumps. Maybe it’s because it will still require electrical grid reinforcement. Maybe because the whole argument for blue hydrogen is being made in bad faith.

I honestly don’t know which. It could be all of the above! Or it could be something that I haven’t thought of.

[1] Pendants and physicists are correct that this isn’t actually an efficiency, it’s a Coefficient of Performance – and hence it doesn’t break any laws of thermodynamics for it to be over 100%.

Posted by simon in The wider world

Reflections on teaching in the pandemic

During this academic year, as well as teaching through a pandemic, I have been working on a PCAP course (Postgraduate Certificate in Academic Practice). A few months ago, as part of the assessment of this, I had to write a number of reflective case studies about my work. These were linked together with a reflective introduction which was quite heartfelt, looking very briefly at the experience of pandemic teaching as a new starter in the context of established theories/models about early academic life. I’m not wholly ashamed of that introduction and I thought it might be of more general interest, and so I’m posting it here with minor edits. It is, of course, very basic: I am no expert in this area and make no claims to novel insight!

The early years of a lecturer’s first permanent role are generally expected to be hard, for multiple reasons: the new academic is coming to understand their new role and identity (Simmons, 2011, Wilkinson, 2018) while also learning the systems of their new institution and, often, developing a large amount of new teaching material. Kugel (1993) described new lecturers initially focusing on self, and then subject. Only later do they shift to considering students, and hence transition from a teaching-led to a learning-led way of thinking – which in turn leads to consideration of more sophisticated pedagogies.

Covid-19, and the resulting emergency shift to online teaching, has added to this load. Watermeyer et al (2021) speak, based on a large survey, of “academics bruised by their experience of emergency online transition… A story of trauma in the face of… profound professional and personal disruption… Of self-concept on trial and in tatters”. The emergency introduction of blended learning has upended Kugel’s progression by forcing staff who are in their first year of teaching, who are still developing self and subject knowledge, to engage very firmly with learning-led approaches. It is not clear whether this is beneficial for students, but it has surely increased the level of rapid adjustment and assimilation of ideas that Simmons and Wilkinson described.

This research feels quite pertinent to my own situation as a new starter. Much of the material that I have been adapting for emergency online learning is material that I have never taught before, and I have been learning to navigate the systems of a university in flux without any knowledge of how those systems work in normal times.

Goffman, as cited & described by Wilkinson (2018), discussed university teaching through a theatrical metaphor. He described “backstage” contexts in which lecturers can stop performing, and “stage talk” where they discuss performance techniques with colleagues. Wilkinson discussed differences in how much backstage space is available for a woman in a male-dominated field, but it is also interesting to consider how these concepts may differ – and how this might affect the development of professional identity – in a year when lecturers are working from home, and are connected to students and peers only during clearly designated periods when their webcams are on.

Posted by simon in Reflective

Six months in

Dear reader, if you ever get the choice, I do not recommend starting your first permanent academic job in the year of a pandemic.

The first year of a job is always hard: you have to create teaching materials for the first time, you have to try to get yourself set up for research and, if like me you’re taking over leadership of a degree programme, you have to figure out a lot of “how stuff works at this institution” and build relationships with a lot of people in a hurry.

That’s the baseline. But thanks to COVID, workload for anybody with teaching responsibilities has increased dramatically beyond that level. We’ve been working really hard to deliver a good learning experience through a “blended” approach, but this takes longer to prepare, and also (despite seemingly having less – but not always much less – face-to-face contact) takes longer to actually run and deliver.

To be clear, this isn’t a criticism of my own institution; it’s something that’s affecting most of the sector. Nor am I unaware of how lucky I am to be in a job right now. But nearly everybody I speak to who has teaching responsibilities in UK HE is teetering on the edge of burnout. This has obvious implications for mental health – it isn’t sustainable, and it will require recovery time – but also slightly less obvious implications for the research side of our careers. Of course having very little time available for research is an impediment, but so too is being constantly exhausted: one just isn’t creative in that state.

Once the dust settles I’m predicting four long-term consequences:

  1. A partially lost generation of early career researchers, who were on precarious and/or fixed-term contracts when the pandemic hit.
  2. A mental health crisis of gigantic proportions across the academy. Some would say that we already had one of those, but this will be worse.
  3. A noticeable difference in research output, and probably also career progression, between people with and without teaching responsibilities.
  4. A similar, or greater, difference in research output and career progression between those with caring or other responsibilities outside work and those without. Greater than usual, I mean.
Posted by simon in Reflective

The A-level results mess

GoT meme: "Brace yourself: Results are coming"

I should caveat this post by mentioning that I know nothing of secondary education, and am not involved in undergrad admissions for my university – so this is purely the view of an uninformed layperson.

As most of my readers will know, there’s a row in the UK at present about A-level results. A-levels are the exams that people sit at age ~18, at the end of secondary school, and are key to getting into universities. As of a few years ago, thanks to the views of Michael Gove on how education should work, they contain no modular exams or coursework and are judged entirely on one set of exams at the end of the year. And this year, thanks to COVID-19, those exams didn’t happen.

Students apply to universities long before they know their A-level results, and so their applications are based on predictions made by their teachers of what grades they will probably get. The universities then make “conditional offers” that commit to providing a place to the student so long as they achieve a given set of grades at the real exams. This has a host of problems that have led some to campaign for years for a change to the system, but that’s a different story.

Thanks to the lack of actual exams this year, students’ final grades have been based on their teachers’ predictions. But for various (mostly sensible) reasons, teachers tend to be generous / optimistic in their predicted grades, and so simply using these would have led to what the government and the tabloids call “grade inflation” – more people getting high grades this year than usual. To avoid this, the regulatory body OfQual was charged with adjusting the predicted grades using a statistical approach. As near as I can understand it, the grades of students in each school were adjusted according to how students from that school usually do. Many have been downgraded from their predictions, leaving them surprised to find they are rejected from their chosen universities. Some smaller number have presumably been upgraded, though we don’t hear about that, and though that won’t impact them as much as they are unlikely to have conditional offers above their predicted grades.

Of course, students are disappointed every year. But there’s a huge difference between being predicted good grades but then failing to achieve them through your own efforts in an exam, and being predicted good grades and then having them reduced because a government algorithm said so – however accurate that algorithm may be when validated through hindcast. One is, ultimately, down to individual performance (albeit in a single exam, which nobody except Michael Gove thinks is a good way of assessing ability), while the other is something that the individual in question is unable to affect.

The task that OfQual were set was clearly impossible to do with any sense of justice. They have probably succeeded in producing a set of national marks which in a big-picture, statistical, sense, reflects what this year’s cohort of students would have achieved. But however good their statisticians, there’s no way that they could achieve that while remaining fair to individuals. As somebody beautifully put it on Twitter:

So given a choice between the problem of “grade inflation” and the problem of arbitrary-seeming marks for students, I find myself asking… is grade inflation really a problem? If, for one year only, the aggregate student body does better than usual, what harm does that cause? This entire year is inherently a set of mitigating circumstances, and there doesn’t seem to be any gain in punishing students even more for the year in which they happen to turn 18.

Sure, an excess of high grades would cause some trouble for the most prestigious universities, as they may not have room to take all the students they gave conditional offers to (I say “may”, because they’ll have lost international numbers this time around). But given how keen these universities usually are to increase recruitment, I’m sure they can find inventive ways to deal with that. Maybe some of the students are even asked to defer to the following year. That feels like much less of a problem than effectively telling a generation of new adults, “What you do doesn’t matter, you will be assigned a place in society according to the school that you come from”.

Given the situation all around us, would it really be so terrible to be kind?

Posted by simon in The wider world

Advice wanted from LGBT / gender non-conforming students

Thinking about my teaching practice, especially as I move towards being a personal tutor as well as lecturer next year, it feels as though I should try to indicate to any LGBT, NB, or other minority students in my class that I’m a safe person to be out to. Obviously I realise that there’s no way of proving that as a hypothetical, and hence some students may always be wary, but is there anything helpful that I can do?

A quick Etsy search reveals various designs of “ALLY” badge… what are are people’s feelings about that? Is there a better idea?

Thanks for any advice.

Posted by simon in Reflective