Whew! Here on the East Coast in the US, it sure is hot in the summer. And there's nothing worse than heat + solar gain. For one reason or another, I often find myself in a hot car alone from time to time, and opt to listen to the radio instead of open a window or two (perhaps a poor choice but I'm stubborn). Wouldn't it be nice if there was a way to cool the car efficiently without running the engine or using up a whole lot of electricity? I can answer that myself: yes, yes it would.
(Note: this idea was inspired mostly by the link below, as I have been trying to think of a way to do what I noted above for over a week now). I propose having a small tank of water with a cooling unit. It would use some electricity from the engine's alternator to freeze it when the engine is on (the tank is also insulated to prevent it from melting quickly). When the engine is not running and a melting occupant activates the system, a low-powered and low pressure fan pumps cold air from the ice into the car. The fans would be mounted fairly low in the car, with the idea that cold air sinks and hot air rises. This would be a lot more effective if the occupant also opened the sunroof (provided the car had one) so that the hot air is essentially pumped out.
Now some car companies have already experimented with small solar panels on the roofs of cars to generate electricity to power fans that keep cars cool. I propose that a solar panel generate electricity to run this system (when it's sunny out of course) and have it just run off of the battery to contribute to the solar panel's juice when it isn't enough. There could be a battery meter in the car, and an automatic shut-off if the battery got too low. But with just a low power fan I immagine it would last quite a while.
Disadvantage: the added weight of the water (20lbs at most however)
Advantage: no longer having to sweat like a pig in a parked vehicle.-- acurafan07, Jul 25 2007 Ice cooling for buildings http://news.yahoo.c...n_re_us/ice_coolingApperently buildings are switching to ice. [acurafan07, Jul 25 2007] It sounds like a good idea, but... It depends how long it would take to freeze the water, and how long the ice would stay ice when the system is not being used, and how long it would take the ice to melt when the system is being used (I know it depends on the temperature of air it has to cool).
If you have a photovoltaic panel, why not just use an all electric air conditioner like hybrid cars have.
Overall I think this would work well in places with mildly high temperatures, and would not work well at all in places like where I live with high temperatures of above 115 degrees fahrenheit.-- BJS, Jul 25 2007 Well the ice would be insulated from the outdoor heat, so if the tank was in the trunk, it probably would only be exposed to room temperature heat (trunks can be insulated, and don't get solar gain) and even then the actual tank would be insulated.
I doubt that an air conditioner powered by a solar panel would always work. First of all, you can't get a whole lot of energy out of a small solar panel. Second of all, it's not always sunny when it's really hot. I imagine the ice would keep from melting for a long time (think of coolers for drinks in the summer time that have un-melted for over an hour even in 80+ degree heat.
Now of course, this could also be used with a small air conditioner (when the solar panel permits) to cool the car even more.-- acurafan07, Jul 25 2007 Oh yea, when the car is running, it would be freezing the water right? ok well, usually when its hot I have the air conditioner on full blast and that isn't even enough always. So if the car has to cool the passenger compartment and freeze up to 20 pounds of water at the same time, well the engine wouldn't have very much power and I'd be getting not so good gas mileage.
Like I said before, I think it would work well for mild climates.-- BJS, Jul 25 2007 Your right, if the A.C. on full blast isn't enough, this would probably do very little.-- acurafan07, Jul 25 2007 The meting occupant could trigger this device such that the ice came out of a hole situated above him. That would make things cool.-- bungston, Jul 27 2007 You're thinking too small for the halfbakery.
The entire autobody should be a hollow flask, containing a hundred gallons of ice.-- normzone, Jul 27 2007 So that would only be approximately 834 pounds or 378.296 kilograms of water added to the vehicle.-- BJS, Jul 28 2007 That'd probably be a little more than the engine could handle to freeze.-- acurafan07, Jul 28 2007 Yes, additional cooling mechanisms would need to be added - and an ice bucket and some glasses.-- normzone, Jul 28 2007 Just install a car-sized freezer in your garage.-- Worldgineer, Jul 28 2007 //The entire autobody should be a hollow flask, containing a hundred gallons of ice// Your car would also expand and contract perceptibly.-- MaxwellBuchanan, Jul 28 2007 Now that's a thought! An entire car made out of some sort of flexible material that can expand, contract, and leak water. Perhaps a jet for an engine with a seat strapped on top?-- acurafan07, Jul 28 2007 Sounds like a Blackbird fuel tank.-- normzone, Jul 29 2007 From the information provided in the link; they use the technology for very large applications like sky scrapers. They used 51,200 gallon of water in one building they talked about. Most of the reason they use ice is so they can use electricity at night, when it is in less demand (when it is cheaper?) to freeze the water, and then during the day they don't use any AC if the ice is providing enough coolness.
Cars don't run off of the "grid" so the cost of electricity wouldn't matter, unless it's an electric car, then this idea might be worth it. I'm no expert though.-- BJS, Jul 29 2007 Hmm you're right about that. It would also work in a plug-in hybrid such as the Honda Insight (although it was discontinued).
I guess a really good situation where this would work well is on a long road trip, where the alternator keeps giving the refrigeration unit electricity to keep the ice cold. You stop for, say, 20 minutes and have to wait in the car alone. It's over 90 degrees and sunny, but you don't want to run the engine and air con. because the engine is already quite hot as it is (don't want to overheat by idling) and you wouldn't want to use more gas than you have to. So you use your ice pump to keep the car at a reasonable temperature until you get back on the road again.-- acurafan07, Jul 29 2007 random, halfbakery