How about this

ajbell wrote: »

Would freezing water in bottles during the day on solar power then putting them in the fridge at night be a saving?.
My fridge and freezer are currently using about 0.5kwh between midnight and 8am.
Would like to reduce this.

That's funny, I've been pondering the same for some time. The main issue being the energy lost if you open the freezer unnecessarily to do this.

But my idea was the same, perhaps a 2lt bottle that you transfer back to the freezer once generation has picked up.

Gonna have to ask Z to do the maths on the energy saved (transferred/stored), but I suspect it gets a huge boost as water is a phase-change material at 0C so straddling that point allows for more energy to be stored.

The same principal applies to Sunamps heat battery which also uses a phase change material, but closer to room temp, to allow for more energy to be stored.

Would the fridge suffer at all from being off for long periods? Also, you could use another trick, which is to dial down the fridge temp* a bit too much, but plug it in via a simple timer switch that cuts the power from say 12pm to 8am ..... total guess ..... no idea what is appropriate ..... will depend on time of sunrise, otherwise it'll come on before generation and work hard on import leccy.

*Edit - just to be clear, I mean set the temp lower (colder) not dial down the power, probably have to 'dial' up the power. M.

You can move your fridge/freezer to a cooler part of the house, and/or stick insulation on the outside of the case to reduce energy use. I've moved my old fridge (1981 vintage!) to the cool larder and it's really not using that much energy now.

There are also people who have converted chest freezers in to fridges. The high levels of insulation and top opening lid (cold air doesn't fall out when it's open) make them very energy efficient. I've seen chest fridge conversions, quite big units, which use about 0.5 kWh a day in total. Maybe one day I'll go this route, but the old fridge is going to have to break in some non-fixable way before that's an option.