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Window AC Generator

Portable Window-mounted Generator
  [vote for,

This idea answers the question, what happens if you cross a window-installed air conditioner, with a portable electric generator?

You get a small portable generator, which you can install in your window!

I'm writing this idea a few days after hurricane Sandy passed through, with grid power still out in my neighborhood, and power supplied to my house from a portable generator.

It occurs to me that people who live in apartments without power have no way of doing something similar, and thought of this idea as a solution.

Basically, the device consists of a very small generator, made to mount in the opening of a vertically opened sash window, just like a portable air conditioner.

Electrical outlets are on the inside, obviously, eliminating the need for heavy-duty outdoor extension cords. Intake for combustion comes from outside, and exhaust from combustion goes to outside.

A lever, or perhaps a thermostat, determines whether engine cooling is done with air pulled from, and discarded to, the interior or the exterior of the building. If you live someplace that's never ever cold, then you'd get a machine which always uses outside air and vents to the outside.

To minimize noise, and because a high power density is valuable in something which will need to be manually moved around, a Wankel engine would be used.

To maximize safety and cleanliness, the fuel should be propane.

There would be two ways of fueling the generator:

Firstly, on the side of it facing towards the interior of the building, there'd be a place to screw on a disposable one pound propane tank.

Secondly, on side of the machine sticking outside the house, there'd be a refillable propane tank, and a propane hose and regulator. The hose would need to be long enough for the tank to rest on the ground, or on a balcony or fire escape.

The machine would switch between the two fuel sources automatically, at need, or manually. Whenever the machine switches automatically from the outside tank to the inside one, or vice-versa, an alarm would sound, warning the user that one of the tanks needs to be refilled/replaced.

Obviously, the machine needs to be small and light enough to mount into a window, but should be big enough to run a refrigerator, several lights, a radio, and perhaps a small kitchen appliance (microwave, toaster, coffeemaker, hotplate, etc.).

It might have an outlet designated as being for the refrigerator, so it can temporarily turn just that outlet off, if the fridge plus other things exceeds it's generating capacity... sort of like a college dorm combination microwave/refrigerator.

goldbb, Nov 02 2012

Small Wankel Generator http://www.geekwire...tic-hybrid-battery/
The datasheet says that Clarian's prototype is 10kg including fuel, and produces 5kW. [goldbb, Nov 02 2012]

Like this? http://www.google.com/patents/US4976114
I don't know if it's baked, but here's a recipe. [Alterother, Nov 02 2012]


       It needs to have a much better seal than most window units, since even propane exhaust can be hazardous.
MechE, Nov 02 2012

       A propane-fueled engine, directly driving an AC compressor would actually be quite efficient, you could take advantage of the cooling effect of the expanding propane, and skip all those pesky electricity generation and distribution difficulties.   

       Such a device would be great for off-grid areas, disaster-zones, field hospitals etc. and would have myriad military uses (would have to use the single battlefield fuel for that one). It might get a little over complex when you need balance between electricity generation and cooling, you'd need at least one clutch... which could get a bit bulky.
bs0u0155, Nov 02 2012

8th of 7, Nov 02 2012

       I had cruised a fair way down your hurricane-inspired idea, wonderin' wot the bluddy 'ell you need AC for, before I realized you meant "alternating current" rather than "air conditioning".   

       Bun, though maybe a dry towel would be better. Good luck!
lurch, Nov 02 2012

       No, AC means air conditioner, even though there is no air conditioner, and there is alternating current. The fifth paragraph is the key.
spidermother, Nov 02 2012

       Meche, you are entirely correct... do you think it should also have some sort of extendable exhaust pipe / chimney, to help direct gases away from the building?   

       Alterother, bs0u0155, Which one of you inspired the other to think that I was writing about an engine powered air conditioner?   


       Spidermother, Please pretend I wrote "as is," in that paragraph, instead of the word "like!"   

       The goal is to have a window-air-conditioner-sized device, but it will in fact be a window-mounted- alternating-current-generator.   

       No actual air conditioning is involved.   

       If, in fact, air conditioning is desired, then we could have a common window AC installed in one window, and an instance of this idea, a window AC generator, installed in another window. If the windows are close enough together, the AC's AC cord will plug into an AC outlet on the AC generator, without even needing an AC extension cord.   

       If you have a preference for direct current, instead, then of course we would modify my idea to become a window DC generator... and you might cool your apartment, by plugging into this device, a window DC AC.   

       Regardless or disregardless of whether or not the current is direct or alternating, and, incidentally, entirely irrelevant to my idea, I generally prefer that portable air conditioners be electrically driven so that they can be hermetically sealed, eliminating the loss of refrigerant... the patent linked to by Alterother has an engine mechanically coupled to the compressor, which makes such a seal impossible.
goldbb, Nov 02 2012

       Shirley you can have the best of both - a hermetically sealed compressor magnetically (rather than electrically or mechanically) coupled to the internal combustion engine. An MaC ICE AC, rather than a MeC ICE AC or an EC ICE DC AC or EC ICE AC AC.
spidermother, Nov 02 2012

       At a minimum you'd want a more balanced unit, and one that both latched onto multiple sides of the window including the sill) and did so with gasketed edges to form a seal.   

       Beyond that, a few feet of pipe to carry the exhaust above (I think propane exhaust rises) the window probably makes sense.
MechE, Nov 02 2012

       Yes, you'll definitely want some sort of flue. There are standards specifying how far an un-flued gas hot water system must be from windows etc. The hazards here would be similar.
spidermother, Nov 03 2012

       // Which one of you inspired the other to think that I was writing about an engine powered air conditioner? //   

       Neither of us inspired the other, rather both of us were likely misled by your opening paragraph:   

       // This idea answers the question, what happens if you cross a window-installed air conditioner, with a portable electric generator? //
Alterother, Nov 03 2012


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