. It looks like the Amazon ones are 240V despite my specifying 12V in search.Oh yes, I quite like that idea, may thanks Sandy
A bag of tesco ice and a frozen 2 litre empty coke bottle of water in a 12 volt cooler or a good insulated cool box is good for 5 days if not more. I know cause I spend many continuous nights at anchor. I have yet to see many marina boats at anchor for long cos they miss their shore power. The harbour master at Waldringfield once said when handing out visitor moorings he is often asked about shore power.
We have a Coleman Extreme coolbox that we use when off-grid camping, it will hold ice for 3 days, and keep milk cool for 5. After 3 days there is more water than ice in the bottom, 5 days for a bag of supermarket ice is a stretch, IMO.
. With solar and modern battery technology energy is more plentiful than ever, so it's OK to have some creature comforts.But ironically whilst you are sniggering at those who “need” shore power you are tying yourself to being within a few days of a supermarket. That might be quite feasible in some areas but it’s not in others, and regular provisioning trips in big areas actually makes using pontoons more likely! A 12V cooler probably uses more power than the solution the OP is asking about (because it runs 24/7 whereas the ice makers claim to need just 15 minutes). I don’t have ice on board - I was actually thinking of trying his current approach, perhaps with some 3D printed parts to hold the bag against the plate and keep the rest of the food away from the plate.
If necessary a 30 minute stop at a decent marina will supply ice. As i said a two litre frozen bottle of water is a big ice brick and last for days, plus your ice cubes from Tesco plus good insulation = 4/5 days. 10 gin and tonics x 2 people x 3 ice cubes per G+T = 60 ice cubes. Problem solved + Paracetamol x 4 for the morning but they do not need chilling.
What you describe as a “decent marina” are not particularly well distributed around the country - but most will charge for a 30 minute stop, and have the inconvenience of rigging the fenders lines etc - I can easily see why someone who wants ice doesn’t want to go to the shop for it and then have the rest of their fridge swimming in meltwater.
The op already has a solution, he’s looking for a better one. Perhaps he sails for longer that 5 days at a time? I’m just back from two weeks on the west coast - I think only one shop we went in (day 3) was likely to have had ice, it was also the only time we used a “marina”. The fridge was pretty full to start with, no room for frozen water bottles, no way to refreeze them when they melt. On the hot days ice would have been nice. I could have bought a very good cooler and found somewhere to store it, giving me option for the first 5 days but that sounds like a strange way to solve the issue if there’s a small viable option that can be used everyday!
How many of the marinas in the area you sail in stock bags of ice cubes or have a local shop that can be visited within 30 mins ?