Summer in Arizona: What options to keep cool?

So I live in Arizona and I wanted to hook up a hybrid system with batteries. My electrical panel faces west and is on the exterior side of my garage. It's a 3 car garage so pretty good size. I was going to install the inverter on the inside wall of the garage but it still gets to over 100 degrees in the garage during the summer (it's not insulated and actually vents to the outside in several locations). I think it vents because my Water Heater is gas and carbon monoxide buildup could be bad. Arizona regularly gets over 110 degrees outside during the summer. What are some options to keep my inverter + batteries cool? I thought of installing a large mini split in the garage but that may eat up quite a bit of my power. What are some other options? I thought about moving my inverter to my bedroom closet (which about 20 feet down that west wall along the south wall of the garage) but I'm not sure if that would be best. Any advice/recommendations appreciated.

Where in AZ?
Temps of 100+ are a problem for batteries and your inverter/charge controller will not like it.
Either find a cooler spot or put in a minisplit for the garage. Alternately you could build a small room in the garage and cool just that room.
I'm up in the Prescott area and my garage is insulated and gets to ~ 80F for max temps. Anything over 90F or so will shorten the battery life.

Mini splits are relatively energy efficient.
You can also get a hybrid mini split that runs directly off of PV panels when the sun is shining, and uses AC power when the sun is not shining.
Obviously daylight hours are when you need it the most, so that is a plus.
Frame out a room for the PV, insulate, install a small mini split.

Rich V said:

Where in AZ?
Temps of 100+ are a problem for batteries and your inverter/charge controller will not like it.
Either find a cooler spot or put in a minisplit for the garage. Alternately you could build a small room in the garage and cool just that room.
I'm up in the Prescott area and my garage is insulated and gets to ~ 80F for max temps. Anything over 90F or so will shorten the battery life.

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I'm in Phoenix and I'm thinking the mini split is a bad idea since it seems the venting is required for the water heater. Any cooling would just blow out of the garage. I could replace the water heater with electric and seal up the garage vents (which I might do anyways) but I wasn't planning on it right away. I've replaced the water heater fairly recently.. it's only about 2 years old. It is on the opposite end of the garage than I was planning to mount the inverter (southwest corner) so I was thinking of building some kind of small cabinet or something and maybe run a window ac unit directly into it? The problem is that I park right next to where the inverter/batteries would be mounted so I don't have more than maybe 3 to 4 feet max from the wall. Additionally, this will need to be inspected and I'm not sure if mounting it in some sort of partially sealed cabinet would pass the city inspection (it's gonna be on grid).

Rich V said:

Where in AZ?
Temps of 100+ are a problem for batteries and your inverter/charge controller will not like it.
Either find a cooler spot or put in a minisplit for the garage. Alternately you could build a small room in the garage and cool just that room.
I'm up in the Prescott area and my garage is insulated and gets to ~ 80F for max temps. Anything over 90F or so will shorten the battery life.

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I like the idea of a room within a room, if op has enough space

Another vote to frame and insulate a small room for the inverter/batteries, and install some thermal control.

Design it big enough for your planned stuff, then design it bigger for when to want to expand it, because you probably will.

What about an evaporative cooler?

BentleyJ said:

What about an evaporative cooler?

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I thought about that but humidity could become a problem since they are basically just expelling water into the air. Here is a couple of pictures of my garage wall and the space I'm limited to as well as the garage vents needed for the water heater. Ignore the mess.

I've actually got more room on the opposite side of the garage (the side with the water heater). It's more like a 2 1/2 car garage so I don't park in that half space but not sure if it would be best to run from the panel on this side over to the opposite side...If I'm gonna run the grid connection a ways anyways, would inside the house be a better fit? I can put it inside my bedroom closet where my Networking/telephone/cable + alarm panel is at and that way it would stay much cooler naturally.

I wouldn't recommend putting the inverter in the house at all due to the noise factor. High frequency inverters need constant forced air fan cooling even with low loads. Low Frequency inverters are less reliant on cooling fans but still need them under some conditions. They also have a big transformer that can make the well known 60 cycle "hum" noise. I would strongly recommend searching the forum for posts regarding excessive inverter cooling fan noise to see what others have said. This will no doubt change your mind about living with an inverter in your house not to mention a bedroom.

Evaporative cooling does have limitations when the humidity gets high in the late summer, monsoon season and looses much of its effectiveness. That said, its really the perfect solution for a garage especially since the vents are already installed and are necessary to allow sufficient air flow. Also, energy consumption to operate the fan and circ pump are still much lower than even the highest eff. A/C system. Lastly, its really not adding that much moisture to the air. You can check the specs on the inverter but most would allow operation up to 90% humidity. Never going to get into this range in AZ.

BentleyJ said:

I wouldn't recommend putting the inverter in the house at all due to the noise factor. High frequency inverters need constant forced air fan cooling even with low loads. Low Frequency inverters are less reliant on cooling fans but still need them under some conditions. They also have a big transformer that can make the well known 60 cycle "hum" noise. I would strongly recommend searching the forum for posts regarding excessive inverter cooling fan noise to see what others have said. This will no doubt change your mind about living with an inverter in your house not to mention a bedroom.

Evaporative cooling does have limitations when the humidity gets high in the late summer, monsoon season and looses much of its effectiveness. That said, its really the perfect solution for a garage especially since the vents are already installed and are necessary to allow sufficient air flow. Also, energy consumption to operate the fan and circ pump are still much lower than even the highest eff. A/C system. Lastly, its really not adding that much moisture to the air. You can check the specs on the inverter but most would allow operation up to 90% humidity. Never going to get into this range in AZ.

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Thanks, that's information I hadn't heard before. I was assuming people didn't place inverters inside because of the safety factor, not the noise factor. I'll check out some options for evap coolers then.

tacomaguy20 said:

Thanks, that's information I hadn't heard before. I was assuming people didn't place inverters inside because of the safety factor, not the noise factor. I'll check out some options for evap coolers then.

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If you go the evap cooler route, do not put the elecronics near the blower discharge. The water here has very high total dissolved solids including salts that do make it into the air stream. Most inverters in my area are inside the garage. My neighbors inverter was installed on an exterior, west facing garage wall. Initally It frequently overheated but was resolved by shading the unit with a small corregated metal cover. I would be more concerned about keeping the batteries happy.

NIFE said:

If you go the evap cooler route, do not put the elecronics near the blower discharge. The water here has very high total dissolved solids including salts that do make it into the air stream. Most inverters in my area are inside the garage. My neighbors inverter was installed on an exterior, west facing garage wall. Initally It frequently overheated but was resolved by shading the unit with a small corregated metal cover. I would be more concerned about keeping the batteries happy.

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So I spent the afternoon today (on the hottest day of the year so far, d'oh) moving stuff around my garage. My car barely fits in the space on the other side, but it does fit, so I've freed up that parking space. I figure I'll mount the inverter and batteries on/near that wall and then use a smaller window unit blowing into it to keep it cool. Maybe I'll build a cabinet around it or just block off that space of the garage somewhat to keep the air from exiting that space too quickly. Evap coolers, from what I've seen so far are kind of a pain since you have to keep them filled with water and I figure I can get a small window unit for cheaper than a swamp cooler large enough to cool 600sq ft of garage.

tacomaguy20 said:

My car barely fits in the space

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And I thought I liked to cut it close....

ricardocello said:

And I thought I liked to cut it close....

View attachment 220030

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Lol the space on the other side has the garage door almost 2 foot further in than that one and the space is 8ft wide instead of 9. But I did have more space in the front than you can tell in that picture. But yeah, I've got to be careful not to hit something. I suppose I can park in the front of the house if needed. I am still not sure what I'm going to be doing with my tools. I don't want to be cutting wood and blowing that air into the inverter vents or something.

Do you have space to build a shed? Like 8x8 or 8x12?

There's nothing you can do except get equipment to stand the heat and hope for the best.

As having lived in central AZ lowland desert for 12 years and am in my first summer of solar install, I don't think anything practical can be done. I have my inverter and battery in the garage.

There's storage requirements for batteries, and you can't put them in the living room. You may be able to give up a laundry room or pantry to put them in, but now the battery size is reduced, but probably OK for residential. Outbuildings are not an option because of HOA regulations for most residents of the state.

tacomaguy20 said:

I thought of installing a large mini split in the garage but that may eat up quite a bit of my power.

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Garage AC is the only realistic option I could come with, but this would be power hungry. Could be 20% to 25% of my daily production.
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Please keep in mind for APS there is no Net Metering. I don't think SRP does that either. One of the salesman that came through here used the net metering rates to try to sell me a system, but these much better rates have not been around for 6 years. These false statements made me think I'd get a power bill of $150. Realistically for a 10 kW installation, I think I will save 30% to 50% on my power bill.

BentleyJ said:

What about an evaporative cooler?

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These are not in common use in the lowland desert of AZ. There's reasons for that. Mostly turns it to a humid mess. I thought it would be a common use thing here, but it is not. Old timers used them but were happy to get AC. One guy recently got one because of how hot it was in his garage and he ended up being not just hot, but hot and humid.

1201 said:

Do you have space to build a shed? Like 8x8 or 8x12?

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In the back yard I could. The electrical panel is on the west in the very front though. It's a ways to run power. I ran 240 from my panel to my far corner (kitchen area) through the attic for my mini split and I think it was about a 100 feet of cable. A shed in the back would probably require more.

chrisski said:

There's nothing you can do except get equipment to stand the heat and hope for the best.

As having lived in central AZ lowland desert for 12 years and am in my first summer of solar install, I don't think anything practical can be done. I have my inverter and battery in the garage.

There's storage requirements for batteries, and you can't put them in the living room. You may be able to give up a laundry room or pantry to put them in, but now the battery size is reduced, but probably OK for residential. Outbuildings are not an option because of HOA regulations for most residents of the state.

Garage AC is the only realistic option I could come with, but this would be power hungry. Could be 20% to 25% of my daily production.
=================
Please keep in mind for APS there is no Net Metering. I don't think SRP does that either. One of the salesman that came through here used the net metering rates to try to sell me a system, but these much better rates have not been around for 6 years. These false statements made me think I'd get a power bill of $150. Realistically for a 10 kW installation, I think I will save 30% to 50% on my power bill.

These are not in common use in the lowland desert of AZ. There's reasons for that. Mostly turns it to a humid mess. I thought it would be a common use thing here, but it is not. Old timers used them but were happy to get AC. One guy recently got one because of how hot it was in his garage and he ended up being not just hot, but hot and humid.

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SRP got sued and so they changed the rules so they do Net Metering but they don't pay a whole lot. I think if I install everything myself and buy a hybrid inverter (I'm thinking the new growatt), it will be relatively cheap and should pay for itself in 10 years... ideally less but that depends on how many batteries I buy and whatnot. I suppose I could just avoid the batteries all together and see how well I do without them. If my garage wasn't vented, it probably wouldn't be as big of a deal to put everything in there and I wouldn't be as concerned but considering it was over 110 degrees today and it's 7pm at night and it's still 105 in the garage, it's probably gonna be an issue.

Enclose the equipment in a fabricated "cabinet" with a 5000BTU minisplit cooling the space. You might use 5kWh/day for a small insulated volume when we hit 120°F.

sunshine_eggo said:

Enclose the equipment in a fabricated "cabinet" with a 5000BTU minisplit cooling the space. You might use 5kWh/day for a small insulated volume when we hit 120°F.

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Yeah I'm thinking something like that. Does anybody know if there are any restrictions on putting an inverter with batteries in a wall cabinet.

NIFE said:

If you go the evap cooler route, do not put the elecronics near the blower discharge. The water here has very high total dissolved solids including salts that do make it into the air stream. Most inverters in my area are inside the garage. My neighbors inverter was installed on an exterior, west facing garage wall. Initally It frequently overheated but was resolved by shading the unit with a small corregated metal cover. I would be more concerned about keeping the batteries happy.

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I just ordered this one, not for inv/battery though..

tacomaguy20 said:

SRP got sued and so they changed the rules so they do Net Metering but they don't pay a whole lot. I think if I install everything myself and buy a hybrid inverter (I'm thinking the new growatt), it will be relatively cheap and should pay for itself in 10 years... ideally less but that depends on how many batteries I buy and whatnot. I suppose I could just avoid the batteries all together and see how well I do without them. If my garage wasn't vented, it probably wouldn't be as big of a deal to put everything in there and I wouldn't be as concerned but considering it was over 110 degrees today and it's 7pm at night and it's still 105 in the garage, it's probably gonna be an issue.

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I was amazed at the amount of work that went into the design, approval, inspection, and fixing write ups in the inspection, never mind the installation. I thought about doing this myself, but am glad I had someone do it.

chrisski said:

I was amazed at the amount of work that went into the design, approval, inspection, and fixing write ups in the inspection, never mind the installation. I thought about doing this myself, but am glad I had someone do it.

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Yeah it's work but it's not worth the cost honestly. The payments for a system 1/3 as big as what I wanted (without batteries) would cost me about 40 dollars less per month than my electric bill. My electric bill has a 32 dollar minimum unless I generate enough electricity to offset that cost (spoiler, I wouldn't). Ultimately I determined that installing solar with a professional installer would end up costing me money (not saving it) and that's not even including batteries. With batteries, it would be way more expensive. And doing a little research and knowing what I could buy a new setup for just didn't make sense. I mean just looking at hardware costs, it would be a fraction of what they were trying to charge me. Inverter + solar panels + mounting hardware, if I was going the cheapest option, I could get a 10kw+ system for less than 6,000, maybe 5500. I want a hybrid system however with batteries so I'm expecting to spend a little more.

BentleyJ said:

What about an evaporative cooler?

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Worthless in AZ during the monsoon