Thermoelectric Cooling Solutions

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Definitions and Notes

Thermoelectric Coolers

ΔTmax Maximum temperature difference at I=Imax ΔTmax rated at Qmax=0, at other Q the ΔT should be estimated as ΔT=ΔTmax(1-Q/Qmax)
Qmax Maximum heat pumping capacity at I=Imax Qmax rated at ΔT=0, at other ΔT cooling capacity should be estimated as Q=Qmax(1-ΔT/ΔTmax)
Imax Current resulting in greatest ΔTmax
Umax Voltage drop at ΔTmax
N Number of thermocouples (pairs of n- and p-type pellets) Every thermocouple consists of n-type and p-type pellets
-xx Thermoelectric pellet length code Pellet length is "-xx" x 10 (in mm)
Th TEC hot side temperature Performance data shown in specifications (ΔTmax, Qmax, Imax, Umax) are given for Th=300K
H Total TEC height All dimensions are given in mm. Dimensions A and C are perpendicular to electric wire direction (See drawings at specifications).
A x B Cold side dimensions
C x D Hot side dimensions

Thermoelectric Generators

Parameter Description Notes
Tcold Cold side temperature For specifications it is equal to ambient temperature Ta=300K (27 deg.C)
Thot Hot side temperature All specifications are given to three hot side temperatures 35, 55, 85 °C. This provides ΔT 8, 28 and 58 °C, correspondingly
ΔT Operation temperature difference Operation temperature difference between Tcold and Thot sides. ΔT=Thot-Tcold
Rt Thermal resistance of TEG Thermal resistance of TEG in direction perpendicular to cold and hot sides (parallel to heat flux Q through the TEG)
N Number of pairs of thermoelements Number of pairs of thermoelements in the TEG
Rteg Resistance of TEG Measured at AC. In Specifications at given ΔT the ACR is given at average temperature between Tcold and Thot
α Seebeck coefficient Seebeck coefficient of a pair of thermoelements of the TEG
Z Figure-of-Merit of the TEG It is temperature depending. Typically 2.7-2.9x10-3 K-1 at Ta=300K
Q Heat flux through TEG Total Heat Flux coming through the TEG. Q=ΔT x Rt
Uoc Open circuit voltage Maximal voltage generated by TEG at given ΔT. Other words it is electromotive force. Uoc=N x α x ΔT.
Isc Short circuit current Current at short circuit. Isc=Uoc/Rteg
Rload Load resistance Resistance of external electric scheme which consumes power of TEG
Umax Maximal output voltage Maximal output voltage and maximal power are at the equity Rload=Rteg
Pmax Maximal output power
m Coefficient of optimal electric load It is given as m=(1+Z (Thot+Tcold)/2)^0.5 ~ 1.3…1.4
Ropt Optimal load resistance Resistance of electric load which provides maximal efficiency of the TEG. Ropt=Rteg x m
nopt Optimal efficiency of the TEG Optimal (maximal) efficiency which can provide the TEG at optimal electric load Rload=Ropt
Uout Optimal output voltage The output voltage at maximal efficiency. Optimal voltage is given as Uout=Uoc/(Rteg *(1+m))
Pout Optimal output power Output power generated by the TEG at maximal efficiency Pout=Uout^2 x Ropt
H Total TEC height All dimensions are given in mm. Dimensions A and C are perpendicular to electric wires direction (See drawings at specifications).
A x B Hot side dimensions
C x D Cold side dimensions