China turns out first solar-powered air conditioner

[The Straight Story]

China turns out first solar-powered air conditioner


China's first solar-powered air conditioner that can also send excess electricity to the power grid began rolling off a Gree Electric Appliances production line Wednesday.

The first 50,000 units will be sold in the American market. After that, the units will also be available for purchase in China, according to company sources.

The air conditioner, independently developed by Gree, mainly uses solar power, using normal electricity only when solar power is inadequate, said Huang Hui, chief engineer of Gree Electric Appliances.

The American government is supporting efforts to send excess solar energy to local power grids, and so the model should be popular in America, said Huang.

http://www.globaltimes.cn/www/english/sci-edu/china/2010-12/600477.html

[spanone]

1. a technological oxymoron

[Tesha]

2. Why do you say that?

One large photo-electric panel can power a room-size air
conditioner and the fact that the solar panel only works
when it's sunny is a pretty good match to the fact that
you mostly need AC when it's sunny (on a sort of long-
term moving average basis).

Tesha

[theophilus]

3. That's a pretty silly statement, I think. If we could power ACs in the hot

sunny summer with solar panels we would really cut down on generated power usage. Really cut down. This is exactly what we need. I just wish we were doing this and not China. We're ALL looking pretty silly.

[robinlynne]

4. exactly the opposite. You need air conditioning when the temp (sun) is hot. It

is absolutely perfect!

[spanone]

5. no sense of humor? lighten up francis...

sorry, no offense intended. it was meant simply as a joke.

[truedelphi]

6. Sometimes you need those smilie things,

To help instruct the folks on when to laugh.

[Wilms]

28. .

[theophilus]

18. I get it, now. Sorry I "jumped on" you. It IS funny, in a way. n/t

[d_r]

21. I thought of it the same way

Using sun light to cool off

[mopinko]

7. about time. so obvious.

something i have been asking why not about for a long time.

[cowcommander]

8. Are solar panels really that efficient now in converting electricity?

Air conditioners consume an awful lot of power, I can't imagine how this is going to work unless this system comes with several hundred square foot solar panels.

[Statistical]

10. You are right.

It likely is a much smaller unit designed for much smaller homes/rooms. Also in many parts of the world AC is used to keep temperature relatively cool. Like setting it on 82 (vs 90+ outside).

In the typical American house, with typical American demands for energy the amount of panels will be significant. If you are going to do all that you might as well get solar power for the whole house.

[cowcommander]

11. So wouldn't it be cheaper to buy a bunch of solar panels from Harborfreight...

...and hook them up to your own small ACs?

[Statistical]

12. I don't know but I think the Chinese solar powered AC will be heavy on marketing.

Runs 100% on solar power *





small print in Chinese in on inside of the box which is written backwards.
"If AC usage doesn't exceed 100kWh annually".

[krispos42]

26. Maybe

The average household A/C unit runs on 120 volts of alternating current and consumes maybe 1,200 watts... that's about 10 amps of current flow.

That solar panel kits puts out 45 watts at 12 volts direct current; that's 3.75 amps. You'd need 27 of the units you posted... minimum. If you want some reserve capacity for when it's a bit cloudy out or when the Sun is low in the sky, you're better off with maybe 36.

Okay, then the wiring: If you wire them up in parallel, you'd be putting up about 100 amps at 12 volts through the wires to the power inverter. That's a decent amount of current and will create a fair amount of heat if the wires are too small. It's about the same amount of power consumed by a car's starter motor, and look how thick the jumper cables for that activity have to be.

Then you have the inverter, which has to powerful enough to turn that 12 volts DC@ 100 amps into 120 volts AC @ 10 amps, and those cost cash, too. A http://www.theinverterstore.com/the-inverter-store-product.php?model=pwri150012s-top-rgb">pure sine-wave inverter of 1500 watts output is in the $400 range.

Finally, you have the plug for the A/C unit itself. The power from the inverter is not going to be synchronized to the power grid, so you can't just add the wires from the inverter to the wires from the electrical grid. You need to either install the inverter plug separately and manually plug the A/C unit into the socket you need (inverter when it's sunny, grid when it's dark) or install some kind of phase synchronizer to make the inverter's AC power match the grid's so you can use the same plug regardless of where the power comes from.


:shrug:

It's doable if you don't mind the initial expense for having free air conditioning!

[lfairban]

30. Maybe it is not an AC A/C

Then you have the inverter, which has to powerful enough to turn that 12 volts DC@ 100 amps into 120 volts AC @ 10 amps, and those cost cash, too. A pure sine-wave inverter of 1500 watts output is in the $400 range.

We don't know any technical details about how this unit operates. You are just assuming it uses conventional A/C techniques. What if it does use a compressor, but the compressor is powered by a DC motor instead of an AC motor. Then you only need the inverter and synchronization for the excess power going back to the grid.

From this article, we don't even know it HAS a compressor. Maybe it runs on peltier coolers. :shrug:

Also, since it has battery storage, you might have overestimated the number of panels that it needs to run. Mornings have light but not usually enough heat to require A/C.

So far I am hopeful, but not convinced.

[NutmegYankee]

16. It depends on the unit.

An 8000 BTU unit can run off of 1000 watts, which a solar panel can produce. Granted, I'm thinking of a roof top panel.

[Pancho Sanza]

19. The panels are optional accessories that you'll need if you want to cool anything larger than a

can of coca cola.

[madokie]

23. We have an old refrigerator that runs off of propane

it has a small flame about the size of a quarter and it'll keep the refrigerator working making ice and everything. I'm thinking that they may be using this type technology rather than a solar panel to make electric, but then again on second thought I thought I read them saying something about feeding back into the grid when there is an excess so who know. I guess its time to go to the link and see what they have to say.

[Codeine]

9. I'm going to take a wait and see attitude on this one.

The power draw on an AC is fucking massive. These are likely tiny little units.

[msongs]

13. my solar panels power 2 window units but NOT the central air compressor....

so we use both window units along with other usual household apps and still the little meter runs backwards. Only draws from the grid when the central AC goes one.

[Pancho Sanza]

14. How large are your solar panels? Full sun only provides about 200 watts per square meter

forgive me if I am very skeptical on your claim...

[delightfulstar]

24. I've thought about taking this approach....

Solar panels are everywhere here in AZ. It would be worth the investment in the solar panels to cut down on the electric bill when the temps soar well above 100° here. How large are the panels you use to do this?

[Raine]

15. America used to be first with so many things

now it seems inventions are another thing that have been outsourced to China.

[Hannah Bell]

20. most exported electronics from china are wholly-owned by foreign companies.

when breakthroughs attributed to "china" check the fine print.

it's not always chinese capital. or chinese science. or chinese engineering.

[HEyHEY]

25. Newp

China rarely invents things on its own. Often it's with a foreign company-partnership.

[Pancho Sanza]

17. I bet they're made by the same outfit that sells those magic bracelets

that use "natural frequencies" to keep idiots from falling down. :rofl:
HAHAHA

[End Of The Road]

22. Hope it works better than Chinese-made microwave ovens. nt

[Swamp Rat]

27. k&r

[hunter]

29. I looked at the company website...

... seems like they've got some innovative inverter/motor control technology.

I'm guessing these air conditioners have variable speed compressors. The more direct current you feed into them, the faster the motor turns, and the more cool air you get up to the unit's rated capacity.

http://www.gree.com/gree_english/gree_news/news_glxw.jsp?opt=interview&id=1825

[Pancho Sanza]

31. Maybe it's partly a matter of poor translation, but that "technology" is vaporware

like the perpetual motion machines that pop up every year or so. It ain't real.

[hunter]

32. Maybe something like this?

http://www.solarpanelsplus.com/dc-air-conditioning

The electronic commutation system of a "brushless DC motor" is essentially an inverter.

http://en.wikipedia.org/wiki/Brushless_DC_electric_motor

[Pancho Sanza]

33. I notice they didn't specify the INPUT watts (or amps). It's easy to run an 18000 BTU

air conditioner off 48 volts of auto batteries for a short time (it's like driving a golf cart nonstop) but their stated minimum 1000 watt solar panels is way too small to give you more than a few hours of operation assuming you can get good full sun to charge the batteries up. I can buy a hell of a lot of 8 cent/KWH of electricity for what a 1KW solar panel (and the batteries and electronics) would cost. Remember, you can not extract more energy from sunlight that is IN it to begin with...which is barely a couple hundred watts per sq. meter in the USA on average.

[lfairban]

34. No it isn't

The electronic commutation system is part of an ebike controller. Most ebikes us brushless motors.

It does NOT have the same function as an inverter. An inverter turns a DC current into an AC current basically the same way that an oscillator produces a square or sine wave.

The commutator in an electric motor controls which of the three coils the DC current goes through and in which direction. It is sort of like the distributer cap in an Internal Combustion Engine. Just as you can eliminate the distributor cap and replace it with a multiplexer, an electronic device that does the same thing, you can replace the commutator with analogous electronics. It is necessary in brushless motors because if you eliminate the brushes and wire the coils directly to the DC input, you bypass the commutator.

The current is DC all the way through.

[hunter]

35. It's not "DC all the way through" even in a brushed motor.

That would be a very inefficient design. And a motor is an oscillator of sorts.

Somewhere in a motor you've got currents flipping back and forth through coils, and thus magnetic poles cycling N-S to S-N and back again.

Even the spark in an automotive ignition system isn't as simple as it looks -- it's also an AC system. Take the capacitor (condenser) out of an old style ignition system and see how well your car runs. The coil and capacitor resonate like a bell banged by the opening and closing of the points creating a high voltage AC signal. This AC signal is further modulated and directed by the distributor cap. In modern cars these AC signals are generated and sent to the spark plugs without using electromechanical parts. Entirely electronic ignitions are more precise and require less maintenance.

Simple brushless DC motors are AC motors driven by circuits like this:



That's pretty much an old fashioned inverter circuit, the kind of inverters that used big heavy low frequency transformers. You could in fact draw a pretty good three phase AC current off this "DC" motor.

[lfairban]

37. I meant all the way through the controller it is DC

I try not to think about what is going on in the motor. It's too confusing.

I also don't like calling brushless motors AC motors. I think there are motors that run off of AC that don't rectify it at all.

Thanks for the diagram, I don't recall seeing one like it. I am not very good at transistor circuits, I started getting into it in the late 70's when Op Amps became popular. Are the transistors FET's? This is the 120 degree Hall sensor configuration, no?

[hunter]

38. It could be any kind of transistor depending on the motor.

Small inexpensive motors will use ordinary transistors.

Traditional "AC motors" are single or three phase induction motors. There's no commutation or rectifiers if they're running at line frequency.

http://en.wikipedia.org/wiki/Induction_motor

[Pancho Sanza]

39. I wonder if you're old enough to remember "vibrators" in car radios...

they were simply mechanical inverters that provided the AC (technically, intermittent DC which behaves much the same way) needed to feed power transformers to kick up 6 volts to 200 or so - enough to provide anode voltage to tubes. ~50 years ago, they were a profitable item for gas stations (along with Camel Tire Patches) :D

[hunter]

40. I built some scary machines using those. ZAP!

You can still buy "solid state" versions for use in antique car radios.

Were those the tire patches that you lit on fire? I always wanted to do that when I was a kid, but my dad wouldn't let me.

[Pancho Sanza]

41. I still have an old Motorola Dynamotor from a 2-way VHF police radio set

it's one of the last ones they made, runs on 12V instead of 6 like most of them did...makes 450VDC and lots of noise! :D

Yes, the tire patches were for tire tubes before tubeless tires. They came on a little metal sort of cartridge that had some pyrotechnic stuff on the side opposite the patch that you would light with a match, it would fire up like gunpowder, get hot as hell and vulcanize the patch onto the tube (it would be clamped to the tube with a screw-down holding apparatus)...I must have done that a thousand times back in 7th grade, my dad bought me a gas station to give me something to do after school...I learned a lot in those 2 years. (1955-56)

[theophilus]

36. Google "Solar Powered Air-Conditioner". There is quite a bit.

One is for an 18,000 BTU unit for under $4,000. I don't know enough to know if this is hooey or not. You might. Times are changing, though. Very slowly.