https://en.wikipedia.org/wiki/RBMK
(some of the design problems have been addressed in the still operating reactors)
I'd argue that any reactor design that doesn't just allow to be shut down and walked away from, is inherently unsafe - it's just that RBMK have far worse consequences when humans screw up, which can be seen as their fundamental flaw, they basically miss a safety net in the form of an auxillary containment. Fukushima showed what could happen in reactors like the ones used in Switzerland - IMO that's way more manageable than climate change, although the question remains whether 'china syndrome' is possible and how such a true worst case would look like. I once did some rough calculations on how much radioactive material is present in typical reactors, and it's really quite staggering - dispersed in bad ways you basically get lethal doses for hundreds of millions of people.
So the only sane way forward IMO is to finally replace all these old designs with ones that have passive cooling systems in an emergency, meanwhile passing housing laws for new houses that require a certain percentage of solar roof, x amount of kWh battery per inhabitant as well as the ability to feed the grid from both roof and battery in order to create a stable renewable grid. Unfortunately no green party is pragmatic enough - their anti nuclear stances mean that we'd have to increase carbon reliance before being able to decrease it, which poses IMO greater dangers than even the worst case imaginable with nuclear. Therefore I'd rather vote for those who want to keep nuclear rather than those who promote renewables.
Even though Ignalia-2 had the most advanced safety features of any RBMK reactor, a condition of Lithuania's EU membership was the plant be shutdown. As such the Baltic states have been very dependant on Russia for energy since the shutdown.
Belarus is in the process of building a plant on the Lithuanian border. Although it's PWR and has many safety features RBMK didn't have, thanks to politics the lack of transparency over safety issues is rather concerning:
https://www.theguardian.com/world/2016/aug/09/belarus-under-...
Is it because those who have to bear the risks (e.g. RBMK on-site engineers) aren't the same who'd pass on information through the administrative chain? Was the main thing missing free information flow? Could communism work if all economic/infrastructure/administration units would just be forced to publish all their data in raw form, so other people could analyse it and make better decisions?
https://en.wikipedia.org/wiki/Pressurized_water_reactor#Mode...
A PWR isn't going to "blow up" when it gets too old, or at all really. Chernobyl, the only large-scale plant to ever actually blow up, had a crazy dangerous design compared to any of these older reactors (and you're not kidding about them being old, they are seven years older than Chernobyl).