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Comment by Qem

2 days ago

> I would love to have an air conditioning / cooling solution that is directly linked to solar panels with no batteries involved.

I think that would be very viable with fridges, that represent a large share of electricity consumption among the poorest. Before electricity, people powered fridges by constantly buying ice blocks. They were just isolated boxes where food was stored together with the blocks. Perhaps it's just necessary to go back at the roots, and make fridges that take energy from solar panels and generate a lot of ice by day, and uses it to keep cold at night, with no need for batteries.

I love this idea but I don't know enough about the specifics. Isn't it really bad(TM) for the pump or compressor or something I don't know about for the input power to be variable like this? Like there might be an errant cloud somewhere.

The whole point of my thought exercise is to see if we can somehow make the cost go down. My understanding is that the panel can easily last twenty five years but the battery you'd be lucky to go beyond eight?

Edit: good news / bad news

Bad news: this is not an original thought

Good news: smarter people than me are already working on this. See solar Variable Frequency Drive (VFD). Basically, my thought is a pump is a pump. if you can build a pump to pump water to irrigate poppy fields, you can use the same pump to drive refrigerant in a refrigerator/ freezer / heat pump.

  • > I love this idea but I don't know enough about the specifics. Isn't it really bad(TM) for the pump or compressor or something I don't know about for the input power to be variable like this?

    No, modern refrigerators and other white box appliances with variable speed motors use electrically commutated (aka EC or brushless) motors that allow for motor speed control. Larger three-phase induction motors can have their speed controlled by a variable frequency drive (VFD).

    > Basically, my thought is a pump is a pump. if you can build a pump to pump water to irrigate poppy fields, you can use the same pump to drive refrigerant in a refrigerator/ freezer / heat pump.

    You’re close, but it’s more ‘a motor with enough power can drive any pump (or fan)’ than ‘a pump is a pump is a pump’, as there are many different kinds of pumps for various working fluids (water, glycol, oil, refrigerant, etc)

    Regarding the fully solar powered A/C, you can smooth out power generation and consumption using capacitors (aka batteries)