Looking for air conditioner for truck bed

Now that our family has expanded it is getting very cramped transporting everyone in the cab of my pickup truck.

I really do not want to trade the truck in for a minivan or an SUV.

I am a truck girl through and through. However, I would really like to find a way to cool the covered bed of my truck so that our big hound dog can ride back there. This would free up a lot of space in the cab. The only issue is that it might get hot in the truck bed. Of course, I never would leave my dog in the car unattended but I would like to find some sort of air conditioner that works in the bed of the truck while he travels back there. I was looking at some of those portable air conditioners that can be plugged into the cigarette lighter but they have very mixed reviews. It seems they are more of a swamp cooler than an actual air conditioner and I don’t know how much help they would actually offer in cooling down the bed of my truck. I saw someone with a real window unit A/C hooked up to the bed of their truck. I am not sure how they are supplying that much power to run the air conditioner though. I suspect the window A/C is only used when the truck is parked. They probably camp back there or something. I guess I am just trying to figure out if there are any really air conditioners that run off of the cigarette lighter that could keep a covered truck bed cool enough for my dog. So far, I have not found any.

New HVAC systems