Add - in front of dEgdT

Co-Authored-By: Cliff Hansen <[email protected]>
Co-Authored-By: Kevin Anderson <[email protected]>

Author: 3 people

pvlib/ivtools/sdm.py

@@ -871,7 +871,7 @@ def fun_rsh(x, rshexp, ee, e0, rsh):
         params['R_sh_exp'] = R_sh_exp
 
     elif model == 'desoto':
-        dEgdT = 0.0002677
+        dEgdT = -0.0002677
         x_for_io = const['q'] / const['k'] * (
             1. / tok - 1. / tck[u] + dEgdT * (tc[u] - const['T0']) / tck[u])