Car Science #7: is anything a good idea?
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I've been forgetting to send this again. But, well, when you've forgotten to send something for ages the only thing to do is eventually send it again innit. And I say 'forgetting' it's more like I've been busy, hopefully I can get it back to weekly now we're in the off season. And I might change up a little bit how I write it - like this week's, which has some 'science around a news bit' as well as the research papers. I dunno if anyone was particularly subscribing to it for anything specific, so: trying things out.
Is there sometimes a good reason to use a methanol reformer?
Long time subscribers will know I have, at best, a complicated relationship to whether methanol is likely to make anything good. Methanol reformers, which split it into hydrogen and carbon dioxide, are even further up my shit list for well, making carbon dioxide as a byproduct of making hydrogen, which very much defeats the point. It made me extremely annoyed when someone touted a methanol reformer car as a way to refuel an EV in 5 minutes - sure, horrifically inefficiently and with it now creating emissions.
But is there, potentially, a purpose for methanol reformers? And is it storage? Maybe. Hydrogen is a pain in the ass to store; it needs perfectly sealed tanks that are incredibly rigid and can't be kept at massively high pressures. Which is one of the problems for the idea of moving it around - and don't get me started on the mad shit the UK government was chatting the other month about replacing natural gas supply to homes with piped-in hydrogen. While 'just setting fire to it' might be the correct response to looking at the situation in the UK, it's not a hugely viable energy policy.
Anyway, back to methanol as hydrogen storage. As Car Science has frequently mentioned, everything about fuels is just rearranging hydrocarbons. Methanol is one, which you can make by getting hydrogen from electrolysis, using clean energy and carbon that you capture out of the air. Or you can just brew some garbage up and ferment it but in theory the synthetic method is the one a lot of energy suppliers are interested in.
Methanol is easy to transport, it's a class 3 flammable liquid rather than a pressurised gas and you can cart around a lot of it relatively easily.
Which makes it quite appealing as a hydrogen storage solution. Especially if you're, say, going to remote locations like Extreme E does and then needing to charge some big old electric off-road cars. XE's current hydrogen fuel cell generators use big hydrogen tanks and aren't as powerful as the potential 150kW generators Kaizen Clean Energy is planning to bring in for its methanol reformer system.
Is it efficient? Not at all. Synthesising methanol is an energy-intensive process that you then only use part of the product of. And you release all that CO2 you just captured, at significant energy cost, back into the atmosphere. It's a way to, effectively, transport liquid electricity but with energy losses both from the creation of the fuel and the reformation process, before you get to the issue of fuel cells' relatively low output.
Ultimately, would using locally-sourced vegetable oil in a generator possibly be more carbon efficient? Potentially, especially when you factor in building fuel cell stacks, which need a fair amount of mined components, much like batteries. So I don't know if the portability is a justification for engaging in what's an inefficient process just to be able to say there's no combustion generator being used.
But it is maybe a better case for a methanol reformer than most of them. There's a similar question about using them in marine contexts; the carbon emissions of a reformer will be less than those of an engine burning fossil fuels and avoid the other, extremely problematic, emissions from ships.
I can't really convince myself, though, that capturing carbon only to release it again is an acceptable solution at this point. Maybe if the climate crisis was less critical, as we head towards 2.5C change, so there was more margin to experiment with optimising this kind of system. Maybe if the whole business of generating clean electricity to make methanol to make slightly less clean electricity made more sense when you write it down. Or maybe I'm just a curmudgeon about hydrogen.
No Brakes
I went to the Jaguar Formula E launch yesterday and there's something I hadn't really thought about when it comes to the Gen3 car. It's got no hydraulic brakes on the rear axle, only regeneration. Which means it doesn't really have brake discs in the conventional sense - in turn, that means it can't create brake particulate dust the same way.
Brake particulates are one of the worse types of emissions from vehicles. If the climate crisis wasn't as dire as it is over greenhouse gases, tyre and brake particulates would be getting a lot more attention as environmental and health disasters. Tyre particulates account for up to 65% of ocean microplastics, while brake particulates pose major respiratory risks and are a significant air pollution issue, especially in cities.
EVs, unless they have a methanol reformer on board, don't have exhaust emissions but both tyre and brake particulate emissions actually might be even worse than ICE cars because EVs are heavier. The real problem, as with everything in 2022, is that we've really not done anything to address these glaring issues over the course of automotive history - and even though we've known tyre and brake particulates are a major issue for more than 30 years. But it's on the list to tackle now, regardless of a car's propulsion system - the Euro 7 standards will also measure and restrict a car's brake and tyre emissions, which is a legislative start to what's a huge thing to fix.
One obvious way to not have brake emissions is to, well, not have brakes. Which feels like an extreme idea because regenerative braking is relatively new - we're only now starting to see road cars pushing over 250kW and most even new cars are hanging around at 100kW or so, in terms of the rate of energy recovered under braking. But regen is the big miracle of Formula E and where the racing technology really proves itself; FE's gone from road car amounts back in 2014 to what will be up to 600kW of recovery in its third generation car, which is extremely important for EV efficiency.
Recovering energy extends range and means smaller battery packs can be used, as well as being kinder on tyres and brakes. If you can actually remove hydraulic braking systems from cars, too, you save huge amounts of weight - so although this is an out-there step that Formula E is taking with the Gen3, it's something manufacturers are genuinely interested in.
I asked Jaguar's technical manager Phil Charles whether something so radical could actually be relevant to road technology and he said absolutely yes.
"A couple of years ago the road car guys were kind of looking over the fence at us but weren't asking too many questions," he told me at yesterday's launch. "I think they kind of looked at the technology and said 'Yeah, it's really interesting. It's a little bit far ahead of us at the moment.' Now they're talking to me all the time.
"And when they first got wind that we were not going to have brakes they were like 'wow, OK, that's a massive weight saving for us.' To be honest, the cost guys came first, they're like 'you're going to be able to take off all the brakes, wow.' And then they told their engineering friends and then some of the engineer guys came over. And so we've had lots of discussions as we've gone through this process, about actually swapping the braking method as well, not just taking off completely.
"Maybe you can use an eddy current brake on the gear in the gearbox. Maybe you can use some of the fluids that you've got almost acting like a parachute. So we've had some really interesting discussions straightaway where we've come to the conclusion that maybe even if it's a bit of a big step now for a road car, there might be some in between steps that can get particulates off the car as well. So these discussions haven't helped us because we're not going to do that fluid idea to slow the car down. But it's been really interesting. We've been involved in that. And I'm really proud of the fact that we're putting this information and these ideas on could be in the next I-Pace or the next whatever."
Eddy current braking isn't new technology and it wouldn't normally make it into here because it's not something people are publishing many research papers on. But in the search for solutions to the particulates problem, the halfway ideas are definitely really interesting.
Plastic recycling: we might not be doomed
Plastic recycling is a nightmare, not least because the third-most-produced form of plastic, PVC, is basically un-recyclable. If you mix it in with other plastics it releases all kinds of dangerous things including hydrochloric acid and toxic plasticizers, all of which plays havoc with a recycling process and which happen with very little provocation as soon as PVC is exposed to heat.
Vast amounts of landfill is made up of PVC because it's a very durable, very mouldable plastic used for everything from gloves to windows. In automotive contexts, lots of car interiors are PVC and particularly wiring is coated in it. Cars have a lot of wiring and it's a waste problem on a lot of levels, from the copper used to all that plastic casing. So recycling PVC is pretty critical, however you look at it.
Not being able to do that was obviously not great. Scientists at the University of Michigan have found an electrolysis-induced method that actually turns PVC into a usable substance, even with other plastics mixed in, though, which is fucking incredible news. It looks fairly viable on a mass scale, since it's plastic-agnostic (sorting through plastics to work out what can or can't be recycled is one of the barriers currently) and we could finally deal with some of the worst of the oil-age waste.
Other bits
Along with the good news that we could get rid of brakes sooner than we'd hoped, there's been some really decent progress in filtering microplastics out of water. We have to do this, it's as crucial as reducing CO2 in the air but right now the techniques are very poor and inefficient. Scientists at RMIT have found a way to use magnets to create a sustainable, sourced-from-waste absorbent that can filtrate extremely small microplastics out as part of waste water treatment.
There's been a lot about silicon carbide around this week; it's the material all JLR cars will be using for inverters now and it's an important semiconductor material for high voltage systems. But it does have a few problems, like a tendency to degrade - so it's excellent that this paper has an answer to that that doesn't impede performance or massively overcomplicate the manufacturing process.
As mentioned before it's always good to be cynical about how 'net-zero' or 'sustainable' fuels actually are but this is one where, ok, it is definitely not zero cost but does have some advantages. Magnesium hydride slurry could, according to scientists, have potential as an improved, longhaul aviation fuel.
I spent a lot of the summer writing about how fucked rivers are, so it's kind of useful that scientists have rigged up Raspberry Pi systems to be able to monitor water levels. Drought is a huge problem, as is flash flooding and both are only going to get worse so having low-cost, low-impact systems that can monitor a river across large stretches is really important.
And that's probably it for this week. I'll actually try and do one on Monday, next Monday. Stranger things have happened, etc.
Hazel
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