Diode across Peltier to prevent reverse function

[fatman57]

I am building a cooling application with a Peltier. I expect the Peltier to not be on the full time, but do not want it to generate electricity when it is not on and there is a temperature differential between the two sides.

Would a diode across the Peltier as illustrated in the image below allow it to function as normal when 12v is applied to the + side and when it is turned off any energy generated by the Peltier will feed back into itself? My hope is this should at least slow down the heat transfer process from the thing it was cooling to the outside world?

I am also interested/worried about how this reverse in flow direction will affect the circuitry of my system, and wondered if this would help protect against that.

Thanking you in advance.

 

[Kiwi]

Would a diode in series be a better option?

 

[(*steve*)]

Yes, this calls for a series diode

 

[fatman57]

Yes, this calls for a series diode

OK thanks, where and in which orientation? I cannot see how a series diode will both prevent the backwards flow of energy but also route it through the Peltier again. Thanks!

 

[(*steve*)]

A diode will only allow current to flow one way.

Places with the anode toward the +ve side of your power supply, it will allow power to flow from the power supply to the Peltier, but not flow in the reverse direction

 

[Chemelec]

Adding the Series Diode Will prevent Back flow into your Drive Circuit, But it will Not improve efficiency.
And "I seriously doubt it could affect the Circuitry of your System".
And it is not possible to re-route this power back into the Peltier.

 

[fatman57]

Adding the Series Diode Will prevent Back flow into your Drive Circuit, But it will Not improve efficiency.
And "I seriously doubt it could affect the Circuitry of your System".
And it is not possible to re-route this power back into the Peltier.

Thanks, I had actually stopped answering because I looked at it again and thought how it couldn't work, but i do need to say thanks to people that used their valuable time to reply.

I think I could get something similar by using pairs of Peltiers and wiring them in series, then use a power supply with double voltage to compensate for normal running and when off one can feed the other - but this is just the first thought into my head haven't looked into it yet. I don't want to sound too stupid!

And thanks for the comment on the circuitry - I was worried what would happen with the reverse of polarity on my PSU for example, but I presume it can handle this.