Low energy air conditioning

dhill

For anyone interested,

Here's a link to my son's company. http://www.trinity-thermal.com They are using thermal technology to lower the use of electricity during peak hours. This is important to the electric providers. If you browse through the site, you'll see the data for their units running in Austin, TX. Eventually, they'll get around to developing a home system that pulls less wattage. They have the design, but it's still in the building stage. I have no doubt that it will work. It's a simple construction that does a complex process. They're going to field test a unit at the developer's house first; I volunteered my house, but they declined my offer.

System2

Re: Low energy air conditioning

cool. i just started doing some research on models that pull <500w or so , i have a few models found so far.

dhill

Re: Low energy air conditioning

I'd be interested in seeing a 500w model. I'm using window units. I have one that is 600 watts, and I run it at night during the summer with no problems. I need a larger unit though that I can run during the evening to cool the whole house. I may be able to do that after I get my new panels and battery bank up and running. I haven't crunched any numbers because that kind of stuff confuses me, but I think with 1100watts of pvs and 800ah bank, I should be able to run a midsize window unit without depleting my batteries. I can run it during the summer days with no problems, and I can always run my genny. Cooling the house is possible, but it's expensive.
That's why I hope these guys get there products working. They're working on something now that can provide 5kw of electricity, more than I would need to cool my house. It may be a couple of years before that projects in production for them though. I've discussed the design with them, and it sounds and looks good in concept and theory, but they still have to produce the unit. The boss, David Anderson, is an interesting person. His knowledge base for electrical mechanics is quite extraordinary. He's much like you would imagine an inventor to be, thinks outside all the boxes, and is constantly tinkering with one idea after another.

niel

Re: Low energy air conditioning

i really hate to burst your son's bubble and yours too, but that will never be that cost effective of a system. here's my way of thinking on the subject. you have essentially a thermal air conditioning system, but rather than heat up vast amounts of soil you are heating up the tanks instead. yes, to cool your house it heats the tanks by transferring those btus of heat to the tanks. now the conventional thermal system will just allow the ground to naturally release the heat at night, but the system your son proposes uses energy to physically remove that heat at night so each btu is seeing double the energy consumption as would normally be seen. it doesn't go by the btu so much as how many times you've moved it.
a better proposition would be a more efficient distribution of that heat without using any more power. it has to allow the heating of the ground or huge tanks in your son's case during the day without the sun or atmosphere heating them, to be released at night without using power a night or you've handled the same btu twice resulting in a poor power utilization curve. the rough equivalent to taking the roof off of the soil to allow convectional cooling at night while insulating it from the sun and atmoshere during the day would be better. because of the isolationing of the tanks this would have a limit to its heat capacity. at least if the soil overheats some heat escapes due to the difference between the air temp and soil temp. if your outside air is 110 degrees in the shade, the soil has to exceed that to start releasing daytime heat buildup. like i said it would be more efficient to release the heat at night, but it caps the capacity of your system and i don't view this as worth it. i hope i explained myself properly for you to understand my viewpoint.

dhill

Re: Low energy air conditioning

Well, I'm sure there's other view points, and I certainly don't take issue with yours or anyone else's. All I know is, those units work. The energy is being used to position the unit to work during the daylight hours without major electrical pull from the unit itself. The unit pulls its electrical load during the evening at off-peak hours, saving money. The unit works effectively during peak hours so that the electrical load is not near the level normally required. Thus, the electric provider doesn't have to worry about brown-outs. It may be equivalent to cutting off one end of the blanket and sewing it on the other end, but in this instance, there's a purpose to the surgery.

niel

Re: Low energy air conditioning

maybe i'm not fully understanding the system as i've read it. if they can tap that cold storage without using the power to move the cold into the house during the day then i'll agree, but i see no way of doing that without using power twice for the same btu. yes it'll work, but not efficiently from an electrical usage standpoint from what i see.
btw it has nothing to do with whether or not you agree or disagree with anything i say as you are free to do just that, but just do it fairly. don't have the attitude that just because i would give an opinion that may not sit well with you that you'll disagree with me later rightly or wrongly as that's childish. if i'm wrong in my opinion on the thermal system your son is working on then please explain how. show him what i've said and give me his feedback so that i can understand, but to automatically defend the system because i differ in opinion or possibly lack the full understanding of the circumstance is not reason to childishly say to me that you didn't differ with me. i surely hope he is onto something, but i still don't see it.

dhill

Re: Low energy air conditioning

Niel,
The one thing I'm not doing is arguing with you. You understand much more about all of this stuff than I do so it would be ignorant of me to argue. I'm accepting that you have an opinion about why this system wouldn't work. You probably understand much better why it would work than I do, also.
The system uses high power at night. During the day, basically all that's being used is a fan to push air around. The air is already cooled. I've seen the units. I've seen them working. I don't know all the technical points as to how they work. They basically store the energy like a battery would store energy and convert it to electricity, only they store energy and convert it to cold air.
Feel free to email those guys and ask them how it works. I defer to them. I'm not trying to advocate one position or another, I'm showing something different here that's working, not trying to explain or convince anyone of how it works.

mike95490

Re: Low energy air conditioning

It's a peak wattage shaving thing, burn cheap electricity at night, and pre chill the water, for daytime cooling when electric rates are high, and it just needs a circulation pump, not a compressor. No new tech, and it does have the overhead of running circulation pumps.
A compressor is a compressor.

Brock

Re: Low energy air conditioning

Yes, it looks like it just does the actual cooling at night and circulates the chilled water during the day. Niel my take is that it isn't moving the BTU's twice, just circulating the cooled water during the day.

Really it's a triple win. First you cool the water off when the ambient temperatures are at their lowest point making the cooling more efficient or I should say more economical (think cooling when it’s 60F vs. 90F). Secondly you load shift to avoid huge power usages during peak times thus saving the "grid". And last if you can take advantage of off peak rates you get twice to three times the cooling for the same $.

System2

Re: Low energy air conditioning

it turns out the little window one i have does run at only about 300-400w depending, so i can run it w/my 600w inverter
during the day that is unless i want dead batteries. but so far havent needed to its been mostly temperate.

dhill wrote:

I'd be interested in seeing a 500w model. I'm using window units. I have one that is 600 watts, and I run it at night during the summer with no problems. I need a

crewzer

Re: Low energy air conditioning

I doubt it's inexpensive, but check out the specs on this room-size AC/heat pump:

http://www.friedrich.com/current/php_model.php?modnum=YS09L10&line=TTHP&PHPSESSID=675a02d91915b3d026ad6d35460d2875

HTH,
Jim / crewzer

BB.

Re: Low energy air conditioning

Hmm Heat pump:

733 watts @ 6.9 amps
7400 BTU/H / 3.414 WattHr/BTU = 2,168 Watts

Electric resistive heater:

115VAC * 6.9 amps = 793.5 watts



The 733 "Heating Watts" might be for input power. 2,168 watts of heat pump "heating " would be at what outside air temperature.

-Bill

crewzer

Re: Low energy air conditioning

The 733 "Heating Watts" might be for input power. 2,168 watts of heat pump "heating " would be wonder at what outside air temperature.

My recollection is that 47 F and 17 F are the two typical test temps. I suspect the unit's cited performance, with a COP of 2168 W / 733 W = ~3.0, was taken at 47 F. My take is that heat pumps are generally intended for mild winter climates (our whole-house system in LA's San Fernando Valley was a heat pump), but I found the A/C's EER spec (12) to be pretty good for the unit's size.

Regards,
Jim / crewzer

System2

Re: Low energy air conditioning

So what is the lowest energy A/C unit?

I don't really need over 5000 BTU's but want the least Power hungry unit available.

System2

Re: Low energy air conditioning

Any one? I have checked the 5000BTU I have already and it draws 800 watts.
it'll cycle once the room is cool but still uses a good bit of KWh.

I would like to find something under Around 400W

Solar Guppy

Re: Low energy air conditioning

http://www.energystar.gov/index.cfm?c=roomac.pr_room_ac

All room ac's, sorted, looks like the carrier is the best at 485 watts for 5200 btus

http://www.brandairconditioners.com/cgi-bin/brandac/ACA051B.html?infoview=description but I can't find one for sale, looks like its discontinued

But I found this

http://www.ajmadison.com/cgi-bin/ajmadison/FAA055P7A.html

Which looks just as good ( 475 watts , 5200 btu ) and low cost @169.00

niel

Re: Low energy air conditioning

air conditioners under 5000btus are rare and most rooms require at least that much so that would be the driving force in their rarity. i did find this one if it interests you and do note that anything that is not a big seller does not afford the pricing that mass production items afford.
http://www.qualitymatters.com/Amcor-Personal-Air-Conditioner-APC2000E-p/qmapc2000e.htm
i personnally understand that a 5000btu unit may be too big, but it won't really draw more power than the smaller units in watthours because the compressor on the small one will run much longer than the larger 5000btu ac unit. both the small and large ac units will be tasked with removing the same number of btus. i do feel that a big difference could be made if the fans were to draw less and the best way for that to happen would be for them to shut down with the compressor's shutdown. now some may argue that the fan helps to cool the compressor and adds to the life of it so, at the risk of adding complexity, a delayed shutdown on the fan could be in order.
if even 1000btus is too large then you may want to check into thermo electrics.

System2

Re: Low energy air conditioning

SKYWLKR wrote: »

Any one? I have checked the 5000BTU I have already and it draws 800 watts.
it'll cycle once the room is cool but still uses a good bit of KWh.

I would like to find something under Around 400W

5000BTU/h @ 800watts is a 6.25 EER (energy efficiency ratio) or 6.25BTU per watt. EER is calculated by dividing BTU by watts and is printed on the energy label on the side of the box. You are looking for 5000BTU/h @ 400watts so 5000/400 = 12.5 EER. Window units with that efficiency are still pretty pricey but a 10 or 11 EER is pretty good and quite affordable. It would pay for itself in a several years.

I have one of the Friedrich units Crewzer refers to in his June 26th, 2007, 12:10 post and posted a few replies but they're gone now. I'll repost them when the web archive posts them, they're not there yet.

Also, niel's point about the fan cycling with the compressor is worth noting, my little Fedders 5000 does not cycle and it uses ~65 watts on high speed, plus it's a little noisy. As far as compressor motor cooling goes, sealed compressor motors use the cold refrigerant gas as it enters the housing for cooling.

Cheers,

Bad Apple

Mangas

Re: Low energy air conditioning

Have you been to Freus' website?