Overunity Heating/Cooling Using the Peltier Device

[dutchdivco]

Trying to answer "Why?"

In my previous 2 posts, I was trying to answer Elias's ?, as to "WHY"
"I wonder why is it encouraged to operate these devices in the 5 .. 10 A range!? When the best COP of these devices happens to be around 0.5-1 A range!

I wonder why the say on and on that Peltier devices are inefficient (10% efficiency) !? when the COP of these devices are normally more than 1. Yes they are right because they always oversaturate these devices with current and waste all of the input energy."
Answer is because 'we' are generally more focused on performance, or results, rather than efficiency.With cars, we actually have a method (although flawed) of readily knowing the efficiency; 'estimated MPG". However, with electrical devices, at least until recently, the end consumer hasn't had a way to know, (and hasn't cared) as to how efficient an electrical device is.And, if the choice has been a more efficient but lower performance device, or a less efficient but higher performance device, we have generally chosen the higher performance, or focused on cost.

Look how many people continued to by large, gas guzzling SUV's, cause of a mis-perception of 'safety'. So, even when we know the efficiency, its not usually our primary consideration.

If I'm using the ion generators in my system, humidity would not be an issue.Jim

[elias]

Yes, this is right, you know, but ignorance, and blindly accepting, is a key here.

These TECs sold out there are REALLY GOOD COP>1 devices, but they are advertised as inefficient coolers, just take a look at the COP diagram I posted on the first page. if you keep the temperature difference of the device less than 20 degree centigrade, and put upto 5A current into the device at about 8 volts then you still are COP > 1. while pumping about 45 watts of heat!!! The energy you are using to do this is 5*8 watts, still this is also heat, so you are actually getting 40+45 watts of heat, by using only 40 watts, at the verge of COP == 1.

So the real COP for heat production becomes: 85/40 = 2.125!!

But the true story is if you limit the current draw to about 1A the COP goes upto 10.

I just wonder ... 10% efficiency mainly told is the WORST efficiency of these devices, and it will happen if you put about 10A of current at about 17 volts into the device and make it BOIL and BURN. Then your are getting 10 percent cooling while heating 100%!

Elias

[dutchdivco]

"Yes, this is right, you know, but ignorance, and blindly accepting, is a key here."
Of course, I heartily agree. And, when I start to 'play' with my Peltiers, i will try a variety of different ways of hooking them up.
This reminds me of a short intrview i heard on the news, regarding electric cars. The person interviewed was from a major auto co., and he was saying 1 of the difficulties they were having; all the accesories people have come to expect; seat warmers, dual reat DVD screens and players, etc. By offering these 'extras' on cars, consumers have come to expect/demand them. They all use electicity, which means car makers have to increase the battery capacity, which adds weight, which means a bigger motor, which means more battery, etc.Basically, they screwed themselves.
Look at how cars evolved; the first ones required a hand crank, to start them.Later, the began to build in accesories and extras. Look at the early japanese caes; very basic, no frills. Again, gradually they began to add in the extras.
But today, the market won't welcome the equivalent of a 'Model A' electric car; basic, no frills.Gotta start out with a delux model, with all the frills, or won't sell enough to bring the price down enough to be competitive.Or, so they say,....Jim