Thread by @rcolvile

Argh - this is such a classic case of bad statistical reporting, of the kind @TomChivers highlights in his recent book. Let me count the ways... telegraph.co.uk/environment/20…

'Hydrogen boilers could cause four times as many explosions'. Gosh - that sounds like a lot! But hang on, you don't actually hear much about boilers exploding, do you? So is this a big problem, then?

Well, this certainly sounds impressive. Except that 22 million homes in the UK have gas boilers. So we're talking about is an annual failure rate of 0.00004% becoming 0.00018%

Also, those figures are for 'fatalities or injuries'. Quite a big difference between the two! How severe are these injuries? How often are they fatal? We don't know!

But actually, this may not be a problem at all - because you can install some equipment that prevents this happening. Which, y'know, we probably would. (Side note: no detail on how much mitigating this mitigating does.)

But the crowning glory comes in the final sentence - which acknowledges that hydrogen boilers would actually eliminate carbon monoxide poisoning which kills 60 people a year!

So it would be perfectly possible - and indeed more accurate - to headline the piece: 'Switching to hydrogen boilers would save lives, says survey'. Between 43 and 60, in fact, depending on how many of those 17 annual gas boiler injuries are currently fatal.

But no, it's exploding boilers on the front page. Sometimes, I despair...

Side note: I have interests to declare on this. @CPSThinkTank published this report, supported by @ryzehydrogen. And I'm generally pro the technology. But still. cps.org.uk/research/drivi…

(Nerdy correction: the actual number of lives saved would depend on how fatal the hydrogen explosions are as well. Sorry.)

Update: @nlitchfield points out that the official numbers on gas explosions and carbon monoxide deaths are way higher and way lower respectively than in the article/study. So maybe hydrogen boilers aren't more dangerous but they will save fewer lives?

https://twitter.com/nlitchfield/status/1423230584164343809?s=20

Also see this from the UK energy networks, reporting the same results, where the takeaway is 'just as safe with relatively small changes to the pipes' - in fact they say with the new valves, 100% hydrogen is actually safer than current system

https://twitter.com/energynetworks/status/1423261460642373635?s=20

Final update: now a @CapX piece capx.co/why-dodgy-stat…