Charging in an enclosed garage

[dwegmull]

Even though I've had my Roadster for over two years now, I have never charged it inside a fully enclosed garage except once. That one time was in a very small one car garage and I had just driven 140Miles. It got pretty hot inside, so much so, that we kept the garage roll up door opened a few inches overnight.

I'm about to move into a house with a two car garage a little over 400 sq-ft. Should I plan to install some extra ventilation? It has typical vents near the ground in four places. The roof is flat and insulated (foam roof).

 

[Bardlebee]

This is interesting. I didn't think about it, but it does make sense that a garage would get hot from the charging. Is this a general concern or hurdle that a new Tesla owner will need to consider?

 

[Yggdrasill]

If the charging is about 90% efficient, the power loss would be around 8.5 kwh. That makes for about 1.8 kW of heat for four and a half hours (if you have a HPWC and dual chargers.)

If you park your car in a hot garage though, I guess the A/C will kick in and keep the battery cool, thus heating the garage further, requiring more A/C. I'm not exactly sure how much the A/C will draw, but I think it can be as much as 2 kW.

Some ventilation might be a good idea. (Maybe temperature-controlled fans?)

 

[Yggdrasill]

Forget my last post. I believed I was in the Model S forum. :tongue:

 

[Yggdrasill]

The Roadster will generate around 1.5 kW for 3.5 hours when charging on a HPWC. I'm not sure to what degree the battery pack on the roadster is cooled, but I suspect it could also draw up to 2 kW.

 

[NigelM]

Here in FL the daytime air temp in my garage easily gets up to >90F in summer so I charge at night when it's cooler. It's my habit just to check in the garage and see what the temp is like just before bedtime and I may open the garage door for a few minutes to let some cooler air if necessary. I don't like leaving the door open all night as snakes like to make a home there (the time I thought I could hear air hissing under my Roadster is another story! )

 

[strider]

I charged in an uninsulated (tar and gravel roof, no interior insulation, same floor-level openings you're talking about) 2-car garage in the flats of San Mateo (East of 101) all last year and it was never a problem. The Roadster will kick on its A/C to keep the battery cool and if it gets too hot will slow down charging. You might want to let heat out to help keep the rest of the house cooler but the car will be fine. Having the Roadster charge at night will help too.

And the garage stays MUCH cooler with the Roadster than it did when I drove my Corvette. The heat that thing would throw off in the summer after coming home from work was bad - I would often leave the door open for a few hours in the evening.

 

[smoothoperator]

It would not hurt to install a ventilation fan that was controlled by a thermostat. I did this in my garage and I am surprised at how often it runs.

 

[NigelM]

Although a ventilation fan doesn't help if the outside temperature is higher than the inside.

 

[dsm363]

They do make solar powered attic fans. Maybe something like that would work.

 

[daniel]

North Dakota can have extremely hot days and then nights when it stays quite warm. I sometimes saw nighttime lows in the upper 70's. I had a whole-house exhaust fan that I turned on at night, once the outside temp was cooler than the indoor temp. If you live in a hot climate, ventilating your garage and charging at night certainly seems like a good idea. Here in Spokane it's not an issue. Though I do charge at night just to be nice to the grid.

 

[Doug_G]

My garage is somewhat insulated, not ventilated, because of our cold winters. But we get hot summers, and it gets pretty toasty in there while charging. I reduced the charge rate to 40A and that seems to mitigate it to a degree - spreads the same heat out over a bit more time.

 

[dwegmull]

Thank you for all the feedback!
I charge my car very slowly compared to most you: 24A!
I will look into a thermostat controlled fan. I might even over engineer the whole thing and add a way for the fan to detect that the car is charging. No point in running a fan during the day when no one is home...

 

[daniel]

It seems to me that the relevant factor is the difference between inside and outside temperature, not whether or not the car is charging. Just set the fan to turn on when it's above a certain temperature in the garage AND cooler outside.

 

[vfx]

.... No point in running a fan during the day when no one is home...

In my last place had a solar powered fan on one of the single car garages. Would run when it's hot and stop at night. Just wish I had two on that space.

I just did a white covering on the other flat garage roof.

 

[fraccy]

I most often charge my roadster in a very.... snug... garage - this is a factor, the smaller the garage the more quickly the air temperature spikes up. Mine is fine just by leaving the internal door open plus this is handy in winter as it helps heat the house when I get back :tongue: Once its blown off most of the heat from the drive I find its usually fine to close the door, though living in the uk haven't much experience of this in particularly hot weather.

 

[chris22104]

I have a fully insulated 4 car garage, and it does get the garage pretty warm while charging. The front fans do come on occasionally. I usually pop the "trunk" open while charging, as it does let some of the heat out of the back battery/pem area. This doesn't help the garage temps, but it does help the pack and pem cool easier and moreso while being charged, and does reduce how often the front fans and pem fan come on.....

 

[jordanthompson]

I usually pop the "trunk" open while charging, as it does let some of the heat out of the back battery/pem area.

That's a GREAT idea!

 

[Lloyd]

My weekend project was to place a louvered vent in a upper corner of my garage to provide a little extra ventilation. I found a good resourse for Custom sized vents.

www.alvcompany.com