Okay, realize that going this route will have some serious difficulties. First is space, you have to have room to carry a small cheap window unit or an expensive Wave 2 type unit, either way a window, door opening or trunk lid will have to be modified to allow the unit to sit so it can vent the hot air outside. You might be able to remove the back seat and build a panel to mount it so the hot air exhausts into the trunk area and out the open trunk as well. The second problem is power and power storage. Lithium batteries and inverters are not cheap as well as a charger which needs a source of most likely grid power. If you can park somewhere you can plug into grid power just use an extension cord. There has been a lot of improvements in power stations with built in inverters and several charging options like the EcoFlo units as far as adding and using additional units to increase the size of your bank, so if you can afford just a little more initially the EcoFlo units might be cheaper and charge quicker than a custom built power supply using lithium batteries. You still haven’t addressed the power source problem. Without a daily good source of grid power, a generator or a lot of solar panels you still won’t be able to recharge or keep the batteries charged up. Batteries only store power not create it. If you are saying you have access to a 110 volt plug in those times you need to cool the car then a cheap window unit and a way to mount or vent it along with possibly an extension cord is all you need. If no grid power then your next cheapest reliable option is a generator. Solar would most likely need to be portable folding panels as you just don’t have enough room to use rigid panels on the roof most likely and you would have to be where the sun shines most of the time. These options could cost as little as $300 or as much as $4,000. The Prius has everything thing you need built in and is proven to work, it just depends on your location and personal situation as to what you can make work for you.
