How best to run AC directly off solar?

[DougC]

I plan on moving to a hot desert climate soon. Due to the amount of
sunny days, I got curious about solar PV options. After reading a bit, I
gathered that using batteries to store power on-site would not be
economical, and grid-tying likely would not be either.

The main use of household eletricity in that region is for air
conditioning. Disregarding the cost of the PV panels themselves, what's
the lowest-priced way to get home air-conditioning to run directly off
of the electricity produced by solar panels?

I am aware of the RV 12-volt units, and I'd guess to run them you'd need
at least one RV battery and a charge controller.... but then the
question is that I'd want the RV air conditioner to switch off
automatically whenever the battery dropped to a certain level. To they
have this function already built in? Or is there any easy way to do it?

Please note that only heat-pump air conditioning units are acceptable
for this purpose--swamp and ice coolers are not useful options.

Also we could assume that this would be in addition to the existing
house cooling system. The solar air conditioner would only ever be run
"directly" off PV power, and the rest of the time, the usual AC system
would run off grip power.
~

 

[Mel]

DougC a écrit :

I plan on moving to a hot desert climate soon. Due to the amount of
sunny days, I got curious about solar PV options. After reading a bit, I
gathered that using batteries to store power on-site would not be
economical, and grid-tying likely would not be either.

The main use of household eletricity in that region is for air
conditioning. Disregarding the cost of the PV panels themselves, what's
the lowest-priced way to get home air-conditioning to run directly off
of the electricity produced by solar panels?

I am aware of the RV 12-volt units, and I'd guess to run them you'd need
at least one RV battery and a charge controller.... but then the
question is that I'd want the RV air conditioner to switch off
automatically whenever the battery dropped to a certain level. To they
have this function already built in? Or is there any easy way to do it?

Please note that only heat-pump air conditioning units are acceptable
for this purpose--swamp and ice coolers are not useful options.

Also we could assume that this would be in addition to the existing
house cooling system. The solar air conditioner would only ever be run
"directly" off PV power, and the rest of the time, the usual AC system
would run off grip power.
~

Except that in hot and dry climates, swamp coolers are a nice, generally
economical way to cool... and I though heat pump air con used less
electricity than normal air con, wouldn't this be more interesting.

 

[Ed]

There is a company in Tampa that just got UL approval for a hot water
based residential chiller. YES you can use 80% efficiency solar hot
water. Costs about 2x a regular system + hot water storage (Assuming
you want to be cool at night as well... easier in the desert than in
FL... Some power needed but only for the pumps and fans... So PV still
needed but only a SMALL fraction of the total electricity.


Not sure of the name but Santa Clara University used their system in the
Solar Decathalon in DC this year.