Powerwall installation - better inside or outside

[jboy210]

Hi,

We have a Solaglass roof and 2 powerwalls on order. They are coming to do the site survey in about 10 days. I am wondering if I should try to push them to do an inside or outside install. Electrical connections is on West side of garage wall and I assume that is where they would install the various boxes and Powerwalls. There is space for Powerwalls on inside of wall where meter and PG&E switch is.

Some concerns. here in the East Bay it gets quite hot in the garage in the summer. Outside peaks at 105F or so, but inside it can get hotter. On the other hand, outside the wall is in the setting sun, so that is hot. Any thoughts?

 

[jjrandorin]

You sure your garage gets hotter than 105 inside it? Normally, inside would be better, simply because there would be slightly less temperature variance and no direct sun.

My garage gets hot as well in the summer, but It tops out at around 80 degrees, when its 110 or so outside. Direct sun would not be good I dont think, if you can avoid it.

 

[patrick40363]

inside your garage.

 

[jboy210]

You sure your garage gets hotter than 105 inside it? Normally, inside would be better, simply because there would be slightly less temperature variance and no direct sun.

My garage gets hot as well in the summer, but It tops out at around 80 degrees, when its 110 or so outside. Direct sun would not be good I dont think, if you can avoid it.

Definitely get hotter inside than out . Pretty sure they did not insulate it before they put up wallboard. And to insulate it now would mean quite of bit of work. My office sits right on top of the garage and even with the office floor insulated you can feel the heat coming in. Thinking about putting a fan on a thermostat in the garage to exhaust some of the heat.

 

[MorrisonHiker]

Definitely get hotter inside than out . Pretty sure they did not insulate it before they put up wallboard. And to insulate it now would mean quite of bit of work. My office sits right on top of the garage and even with the office floor insulated you can feel the heat coming in. Thinking about putting a fan on a thermostat in the garage to exhaust some of the heat.

We have an exhaust fan on a thermostat that helps send the hot air out of the garage. At one time, I thought about getting one that is solar powered but now that we have solar and Powerwalls, everything in our house is solar powered. We insulated our garage and while it can still get hot on those 90 degree days, the air flow definitely helps. It's not a the stifling oven like my father's garage. Whenever I try to charge my Model S in my father's garage in the summer, it's so hot that the battery cooling kicks in...which makes the garage even hotter. I end up having to charge with the window and garage door open.

As for your Powerwalls, I would think you would probably want them inside but your situation may vary. If they didn't insulate it, you might be able to do spray foam insulation where they would drill some small holes and inject it without removing the drywall.

You should mention your concerns to Tesla and see what they suggest.

 

[aesculus]

Tesla will help you decide from a technical aspect. But you should also consider what you might need the inside space for in the future (cabinets?) that could not be accommodated outside.

 

[jboy210]

We have an exhaust fan on a thermostat that helps send the hot air out of the garage. At one time, I thought about getting one that is solar powered but now that we have solar and Powerwalls, everything in our house is solar powered. We insulated our garage and while it can still get hot on those 90 degree days, the air flow definitely helps. It's not a the stifling oven like my father's garage. Whenever I try to charge my Model S in my father's garage in the summer, it's so hot that the battery cooling kicks in...which makes the garage even hotter. I end up having to charge with the window and garage door open.

As for your Powerwalls, I would think you would probably want them inside but your situation may vary. If they didn't insulate it, you might be able to do spray foam insulation where they would drill some small holes and inject it without removing the drywall.

You should mention your concerns to Tesla and see what they suggest.

Your father's garage sounds like mine. During the summer when I put the X into the garage the cooling fans will start up because it is so hot in there. Just cracking the garage and a side door help a lot by getting a cross breeze flowing through the garage. But it also leaves the garage open to cats, skunks and other critters that seem to roam our neighborhood.

 

[jboy210]

Tesla will help you decide from a technical aspect. But you should also consider what you might need the inside space for in the future (cabinets?) that could not be accommodated outside.

Good point. My wife does not want the powerwalls in the garage because of the space they take. The space where they would go has shelves now and we would have to find places for all that stuff.

 

[aesculus]

Good point. My wife does not want the powerwalls in the garage because of the space they take. The space where they would go has shelves now and we would have to find places for all that stuff.

If direct heat is an issue you can probably install something like this on the eave/soffit and roll it down the few months a year you need it.

 

[GenSao]

We have an exhaust fan on a thermostat that helps send the hot air out of the garage. At one time, I thought about getting one that is solar powered but now that we have solar and Powerwalls, everything in our house is solar powered. We insulated our garage and while it can still get hot on those 90 degree days, the air flow definitely helps. It's not a the stifling oven like my father's garage. Whenever I try to charge my Model S in my father's garage in the summer, it's so hot that the battery cooling kicks in...which makes the garage even hotter. I end up having to charge with the window and garage door open.

As for your Powerwalls, I would think you would probably want them inside but your situation may vary. If they didn't insulate it, you might be able to do spray foam insulation where they would drill some small holes and inject it without removing the drywall.

You should mention your concerns to Tesla and see what they suggest.

Inside the garage is better for security and the health of the batteries. Keep them warm on a cold night.

In addition to the above comment, consider installing a radiant barrier for heat mitigation. Can be a easy DIY.

Radiant Barriers

 

[JayClark]

I chose inside garage for security mostly. But also, my impression (on the whole) is the batteries work harder to keep warm when it's cold, than to stay cool when hot since in home use these batteries are dealing with relatively light loads compared to a regular 50-200kW heat generating loads that batteries experience in cars. My PWs cruise along a 1kW or lower or so 95% of the time, occasionally in summer zooming all the way up to 6-8kWs.

Most of the reports I've noticed on these forums of unusually high vampire drain, seem to be during cold weather situations, usually when the PWs are outdoors, but haven't noticed posts about unusually high drain in hot weather. High drain yes, but not like the insane drains when the batteries are trying to keep warm, or warm up for use.

I'd rather the PW be in doors protected from the elements, and kept relatively warm near charging cars and such for 6-9 months of the year (at least in Arizona), vs worrying about staying cool in summer, where we hit 110 or higher for 1-2 months each year - my impressions this isn't much of an issue for these batteries as compared to the work they have to do to stay at a healthy warm temperature.

That said it does get up to 120 degrees here for a few days each year, and when we get above 105-110, I usually crack my garage door, that helps vent 20-40 degrees of heat usually, except for maybe a few hours a day - and my garage is insulated.

 

[reddy]

Ours are in the inside, but perhaps our temps are more extreme than yours.

My garage door opener from Chamberlain has a built in temperature readout.

In the winter, when it's 10 degrees outside it may be 40 degrees in my garage.

In the summer when it gets up to 104F, its about 89 inside. That's the hottest I've ever seen inside the garage. Most of the summer it is around 75- 83.

Add in the protection from wind, dirt, snow, rain, hail, animals, etc. IMO you're better off inside.

 

[d21mike]

Inside for ours. And opposite side of garage from the utilities so more conduit was needed.

 

[jboy210]

[

Ours are in the inside, but perhaps our temps are more extreme than yours.

My garage door opener from Chamberlain has a built in temperature readout.

In the winter, when it's 10 degrees outside it may be 40 degrees in my garage.

In the summer when it gets up to 104F, its about 89 inside. That's the hottest I've ever seen inside the garage. Most of the summer it is around 75- 83.

Add in the protection from wind, dirt, snow, rain, hail, animals, etc. IMO you're better off inside.

Do you run A/C into the garage? If it is 104 outside for any period of time how does the garage stay so much lower.

 

[charlesj]

The other consideration is winter low temperatures. If it gets to 50F, and power fails, you have an issue with the battery.
There are a few posts about this, battery will not charge from solar extra power.

Is there space for them inside the garage some other location, not too far from the meter panel?
Running conduits inside is not that hard for the installers and will keep them above 50, hopefully, unless your garage gets colder.

I have 2x6 garage walls, insulated and 12" in the attic above the garage; also insulated garage doors. Don't think I ever saw temps getting that low.

 

[reddy]

[


Do you run A/C into the garage? If it is 104 outside for any period of time how does the garage stay so much lower.

The garage is insulated, and shares 1 wall with the air conditioned house.

The garage door is white, and stays cool.

It's never been above 89 in my garage, or below 40.

 

[bob_p]

We installed our 4 PowerWalls in the garage - in two stacks of 2 PW. The electrical equipment is located on the opposite side of the wall outside, so they were able to run the cabling for the PowerWalls through the wall behind the PW - so we don't have any exposed conduit inside the garage - and didn't have to do any sheet rock/painting to cover up cable runs.

Our garage isn't insulated (Houston) - two of the walls and the ceiling are insulated with sprayed foam. The front of the garage has the garage door - and the wall on which the PowerWalls are mounted are hollow with no insulation.

Even when it's hot outside, our garage stays cool - so the installer recommended installing inside the garage (we should have enough space to add 2 more PowerWalls on that wall in the future, if we decide to expand the system.

The PowerWalls should operate better inside, with a smaller temperature swing. And while we were concerned about the impact on parking our S next to the PowerWalls - that turned out not to be a problem, even with 2 PWs stacked together.

If the PowerWalls are installed inside a garage that does get hot, might make sense to install one or two temperature-controlled exhaust fans if the temperature outside is cooler than the inside temperature...

 

[rogerbohl]

Northern CA, 1000' elevation, near Santa Rosa. Due to property configuration, it appears that we will have a free-standing 2-powerwall installation far from any building. From what I see, the most economical configuration would be a pair of 4" x 6" posts, about 3' apart, with a 4' x 4' 1" plywood "wall" between them with one Powerwall on each side, facing E-W. I would envision a small, shingled "roof" to provide some protection from rain and sun. Comments?

 

[GenSao]

An option would be to do a L-shaped structure (or square) with the powerwalls on the "inside" portion facing north and east. Doing this would protect both Powerwalls from the afternoon sun and hide them a bit.

Furthermore, you may chose to fence or enclose the remain two sides for security. The Powerwall power switch is easily accessible.

 

[jboy210]

Northern CA, 1000' elevation, near Santa Rosa. Due to property configuration, it appears that we will have a free-standing 2-powerwall installation far from any building. From what I see, the most economical configuration would be a pair of 4" x 6" posts, about 3' apart, with a 4' x 4' 1" plywood "wall" between them with one Powerwall on each side, facing E-W. I would envision a small, shingled "roof" to provide some protection from rain and sun. Comments?

Could you build a little shed with a door? I would not want critters and things getting to the PWs. Or anyone flipping them to off. Maybe something with a concrete pad for the weight (300 pounds each).

BTW, nice Mooney picture.