Thermoelectric

Maybe a dumb question, but has anyone mounted Thermoelectric modules on the underside of a PV panel to use the same basic surface area to generate additional wattage with the heat? Sure they have lower efficiencies, but...

I haven't even looked at the specs, prices, etc. on thermoelectric stuff, but a conversation with a guy who bought my motorhome today made me think about it. One benefit of solar panels is that they absorb the heat and dissipate some of it via convection so perhaps helps reduce the heat load on the roof of the coach...

Just wondering...

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Thermoelectric

    You need a fairly large temperature differential to get any sort of "useful" energy from a TEG (thermal electric generator module).

    For example, a quick search found:

    http://thermoelectric-generator.com/wp-content/uploads/2014/07/Spec-TEG2-07025HT-SS-rev.pdf
    TEG2-07025HT-SS is a unique hybrid module. As long as a DT is applied to the module surfaces DC current will be generated. The module incorporates several unique engineered processes that allow it to withstand temperatures up to 190°C (374°F) hot side. The P and N elements incorporated in this module offer the greatest heat transfer capability in a 40 x 40 mm configuration, resulting in the highest potential power densities.

    Power ratings at various DT ‘s (temperature differentials)

    Delta Celsius/Voltage Match/Current Match/Watts Maximum
    50 .6 1.1 .66
    80 1.0 2.0 2.00
    100 1.3 2.2 2.86
    120 1.4 2.4 3.36
    150 1.8 3.0 5.40
    170 1.9 3.2 6.08
    180 2.0 3.4 6.80

    The maximum cell temperature is around 80C on a solar panel (maximum rated PV panel temperature)--And if you stuck the other side into melting snow--You would get around 2 watts from a 40x40mm (1.6x1.6 inch square) module.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Thermoelectric
    BB. wrote: »
    You need a fairly large temperature differential to get any sort of "useful" energy from a TEG (thermal electric generator module).

    For example, a quick search found:

    http://thermoelectric-generator.com/wp-content/uploads/2014/07/Spec-TEG2-07025HT-SS-rev.pdf



    The maximum cell temperature is around 80C on a solar panel (maximum rated PV panel temperature)--And if you stuck the other side into melting snow--You would get around 2 watts from a 40x40mm (1.6x1.6 inch square) module.

    -Bill

    Just to make it easier to look at:
    Delta Celsius/Voltage Match/Current Match/Watts Maximum
     50                .6           1.1              .66
     80               1.0           2.0             2.00
    100               1.3           2.2             2.86
    120               1.4           2.4             3.36
    150               1.8           3.0             5.40
    170               1.9           3.2             6.08
    180               2.0           3.4             6.80 
    
    SMA SB 3000, old BP panels.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Thermoelectric

    Thank you inetdog.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset