Re: "Meters that allow you to do that sort of thing have existed for at least 40 years. "
I could have any color thick-wire Ethernet I wanted, as long as it was yellow. Got a bit expensive special ordering plenum rated cables, but avoided potential issues with minions getting their vampire on and tapping into the wrong LAN
Now you are showing your age. It was (just) before my time, thin ethernet (a.k.a. 10base2) had taken over in the sort of businesses I worked with back then.
But hook solar to a well insulated hot water cylinder and consumers get 'free' hot water
Yes indeed. And roll on a few years, a lot of people are going to be scratching their heads where the **** to put a HW cylinder in their modern shoeboxes designed on the basis that a combi gas boiler is the best thing since sliced bread.
I grew up in a home with a hot water cylinder, which was in an airing cupboard. Which also doubled up as a warm place to let yeast do it's thing for bread and beer making.
And also good for keeping things like towels nicely dry.
Currently though, hot water cylinders are consider 'inefficient' because they 'waste heat'.. But only if you let that go to waste. Otherwise any heat is just going to escape into a home, and warm it.
Absolutely. Not only that, but combi boilers have their own inefficiencies. For example, some can take ages to get hot water out from cold - hence the availability of devices like Combisave which is a thermostatic valve to restrict water flow until it reaches a certain temperature, which avoids the usual situation where the occupant runs the hot tap at high flow to waste a lot of water and a lot of heat while the boiler takes ages to get up to full temperature (it takes longer if you draw all the heat out running the "not hot yet" hot tap direct to the drain).
We have a couple of rental properties. 14 years ago now I fitted a thermal store in one of them, and while it was empty I was able to do some measurements by running it off the immersion heater for a few days and take lecky readings to see how much energy was being used. Even though it's in an unheated garage under the flat, it's standing losses are just 80W - I built an insulated cupboard around it. Around the same time I bought the property next door which still has a combi boiler. In "ECO mode" it goes cold and can take a full minute to supply anything even resembling warm water. With ECO mode off, it's standing losses were around 160W - based on gas meter readings over a few days and converting using the calorific values given on the bill. OK, to that mostly still goes into the property, but it's still higher losses than my "inefficient" thermal store. And the thermal store also runs the heating - so the boiler doesn't have to sit there short cycling for many hours/day.