Geo Thermal Heat pumps. Theory and operation from Sibley.

Well I really don't believe in a system over 100% efficiency, just like I don't believe in a system below 100%. Every closed system (even though we know they do not exist in real life) will always be in a state of unity when we account for all of the energy going into and out of that system.

If you ask me the term COP is just a way of creating confusion, so that machines like heat pumps and others aren't reviled as what they really are: A system of processes which go against the first heat law.

But I still agree with you oOoxelAoOo, heat pumps a awesome!
Also a great video!

Heat pumps are awesome, the reason they appear to be more than 100% efficient is because you get a bigger thermal energy difference than the electrical energy supplied to the compressor in the system. So technically you can't calculate their efficiency, but you get a performance factor instead.
Annoyingly if you switched this around and tried to make a heat engine, it wouldn't work :(

What? Thermal difference is real energy, for example you could drive a Stirling engine on heat difference.

The total heat stays the same, yes, but the secret of heat pumps is that they actually reverse the heat law that causes heat to go from hot to cold. In a heat pump, for example in a cold climate, heat can be absorbed from the outside cold air into the hot inside air, with over 100% efficiency!

This whole concept of "moving heat" is just a farce used to distract the observant scientist.

In thermodynamics, thermal efficiency is defined as: what you want/what you pay for. So when you take something like a heat pump where you get more thermal energy transferred than the work put in to get that change. You'd get an efficiency greater than 1. The first and second laws of thermodynamics state that nothing can be 100% efficient so you have to call it a coefficient of performance.

You're right about heat engines working on the same principle, but the heat pump in the video is a vapour-compression device. Like you get in a refrigerator, only working in the other direction. If you removed the electric motor running the compressor and supplied heat to the system it wouldn't work as an engine, or at least wouldn't generate much useable work.

I work for a company that puts about seventy geothermal units per year, mostly residential units. I must say, the guys did a good job but i would like to know what they charged to put that new heat exchanger in. I bet a new geothermal unit with ten year parts and labor warranty for around six grand after tax rebates and credits would sound better.

$1,100 including replacing one of the 3 pump motors. I just bought this house 3 years ago and it was supposed to be a working unit. I have had enough expenses fixing this place up, so replacing the whole thing did not seem like an option. If everything fails at once, I may do it.

My backup heat doenst come on often. It was -27 degrees here last week and the Heat exchanger keeps the house cozy, but when you need to turn it up, the backup comes on in addition so they both run. Folks around here all have backup gas heaters. This was my first experience with the system, as I never had one in California, for sure. LOL

Folks around here in the Midwest, seem more interested in taking time and trying to save people a few bucks or at least maybe get us by a while longer, and I had just moved here from California, where I lived 50 years in Orange county and it is much different attitudes. They tried and failed, so I had to buy a heat exchanger which was close to $1000 plus labor. I dont think it is that funny. I thought it was thoughtful to try.