de-salination energy cost per liter fresh water

[Gabriël]

anyone have a clue as to the electricity cost per liter for a home sized model?

[___]

44 minutes ago, gabriel said:

anyone have a clue as to the electricity cost per liter for a home sized model?

Your best bet is probably to look at a marine water maker. Looks like it's around 5k for a small hand-operated unit to 50k for the kind of thing you'd put in a yacht. The 50k model (from the ebay page, only place I could find a price) has a 1.5kw motor and makes 55 US gallons or 200 liters an hour. So from that basic bit of research, a kiloliter will cost you 7.5kwh in energy, let's say 8.

[___]

Alternatively, you could buy one of these water from air machines. They are around 22k ex vat, make 35 liters a day, and use around 400 watts continuously to do so.

[Gabriël]

On 9/12/2017 at 12:18 PM, plonkster said:

a kiloliter will cost you 7.5kwh in energy, let's say 8.

that's still way cheaper than the stuff you buy at picknpay - there must be a fortune in bottled water!

some of you might remember the 1970's movie 'soylent green', somehow the scarcity of water made me think of it.... dunnow why

cya!

[pilotfish]

On 9/12/2017 at 12:20 PM, plonkster said:

Alternatively, you could buy one of these water from air machines.

I was looking at a water-from-air machine the other day (in sympathy with our Capie cousins, I live in Joburg with plenty cheap water and have a very productive borehole powered by PV) and it turns out that it is just a heat exchanger that produces condensation at the cool element that is collected at the output.

That sounds very similar to me to the operation of and air-conditioner, which as luck would have it also produces a lot of condensate which is currently dumped into drainage systems and treated as effluent at great cost.

What would happen if it became law that all condensation from every aircon/heat-pump etc in any building above a certain size (say 2000m2) had to be captured and re-used in grey water systems for that building, how much water could be saved?

[Mike]

and they only work to the rated capacity if the humidity is good. So far ones tested here in CT...30lt unit producing 7lt per day with low humidity and a 20lt unit producing 4lt per day with same low humidity...

[SilverNodashi]

On 1/18/2018 at 4:15 PM, pilotfish said:

I was looking at a water-from-air machine the other day (in sympathy with our Capie cousins, I live in Joburg with plenty cheap water and have a very productive borehole powered by PV) and it turns out that it is just a heat exchanger that produces condensation at the cool element that is collected at the output.

That sounds very similar to me to the operation of and air-conditioner, which as luck would have it also produces a lot of condensate which is currently dumped into drainage systems and treated as effluent at great cost.

What would happen if it became law that all condensation from every aircon/heat-pump etc in any building above a certain size (say 2000m2) had to be captured and re-used in grey water systems for that building, how much water could be saved?

I actually thought about this as well. My brother is in CT and had a 90000 BTU install recently. They just need to capture and store the water for usage. I doubt if their unit will produce 35L per day - but it would be worth it to see how much they can get.