Hello- I just got a house with a garage on 03/01/2026 for the first time in a long time. I've suddenly realized the lithium battery in my 'Blue P' is roasting! I've researched as best I can, and the only advise seems to be park it outside with a car cover (!) - not happening. This is my 2nd Prius, I traded in my 2011 for the 2016 Prius Gen4 - bought new in 2016, now has about 25,000 miles on it. I'm retired and don't drive much, obviously. House & garage has a west exposure, 2 car garage, so it gets really hot in there. I'm in the Tampa Bay area, not near water. I've just gotten 2 thermometers that show temp & humidity blue-toothed to my Galaxy S25 phone. I've order 2 round high powered floor fans (not commercial high powered). Plus, I have one pathetic box floor fan. As my neighbor does, I began leaving my overhead garage door open about 1-2 ft in the day time. The side door to the yard has a small window I leave open, so hopefully, there is a little cross ventilation. The daily highs are already running in the high nineties outside. Where should I place the fans to get the most out of them? Point one at the ceiling to blow down hot air, and the other on the floor towards the 2 ft opening to blow out hot air? Should I open all the car windows, put the junky box fan in back seat pointed at backseat window - sort of over the battery area? Any other suggestions or ideas? I'd appreciate any and all help anyone can provide. Thanks, Anne P.S. As a 2 time Prius driver, having been subjected to all the scorn, I must point out, for anyone who does not own a Prius, I get between 64 and 68 mpg, and I'm a pretty fast driver.
What shape is the garage? Does it have a peaked roof, where you could have an exhaust fan in a gable? Is there some way to arrange for the air that comes in, to replace what's exhausted out, to come in from an underground space, like a crawl space?
Great ideas! and yes it has a Gable roof over the garage, unfortunately, it is a rental property (an important fact I forgot to mention). There are not 'underground; options in coastal Florida. It's an average block house - not elevated, built in the 80s I think. But thanks for the quick response and great ides - in other circumstances! Regards, Anne
Well, maybe you could still lay a duct in the ground to bring air through. At high tide you could call it a swamp cooler.
You may be overthinking it. A hybrid battery is at risk if it overheats while being used; not so much when parked. My experience in a very hot environment in Central Texas is garage cooling via ventilation or actual ac is not needed for the car. The interior of the car is far cooler in a garage than when parked outside. Fans to lower temperature in a garage even with open windows and a slightly open garage door just don't reduce the temperature much. I do that when I am working in there since humans benefit from an evaporative skin effect. This is my closed garage covering August 2025: The outside temperatures were higher than 95f fifteen times during the day while nighttime minimums were around 70f. The average in the garage with two cars operated daily was 80.8f which is not bad. I believe the key to hybrid battery reliabilty is to use it a least weekly for 30 minutes of more. Obviously garage ac would be ideal but costly to install and operate. A few have it but its primarily for those with $200k cars or people who have a hobby.
Our 2 car garage can get pretty toasty in summer, doubly so if fully warmed-up car is parked. The two, west-facing garage doors were solid wood, but now replaced insulated steel, which helped "some". Through last winter I got in gear: on the east wall (also exterior) I installed a 16{", 1100 CFM, wall-mounted exhaust fan with magnetic louvres, towards the north end, and at the south end of the same wall, separated by over 10', a 24" square intake air grill with gravity louvers. Wall mounted below the fan I installed a thermostatic switch. Time will tell how much all this regamarole will help, supposed to be a warm summer here. overall, interior Close-up, fan and thermostat Exterior: Close up of the make-up air grill and frame; I incorporated a removable bug screen in the frame. There's an anti-rodent screen as well, on the exterior side
I suggest purchasing a multi-layer car cover. I’ve found 5 layer ones on line. The discussions of fans, etc. miss what is happening. They only move the hot air around. If the temperature is hot inside the garage AND also hot outside, you might lower the garage temp by maybe 10 degrees. I would keep the car windows closed and cover the car. Simple to do. Just my option.
If your garage doors are dark colors, they will easily absorb more heat from the sun. Consider painting them a lighter reflective color that still blends in nicely to your house. Also you can consider insulation panels for inside the garage. I think Home Depot and Lowes carries them. Best to look for professionals to install them. Might already be companies that do that out there. No guaranty it will cool down your garage if the heat is also coming from the roof.
