How to rectify Error compiling Simscape Network

This is the error I get and I use Matlab 2018a

Error compiling Simscape network for model acgrid3source_line.

Caused by:

• ['acgrid3source_line/Solar panel1/Solar module (72 cells)1/36 solarceel/18 solar cells/6solarcells/Solar Cella']: Failed to compute value for parameter, x.
• No matching signature found for exp. exp takes one dimensionless argument.
• Argument 1 = {2901.1263, 'K*V/J'}
• Voc = {10, 'V'}
• vtm1 = {0.0034, 'J/K'}
• In elec.sources.solar_cell ()
• In elec.sources.solar_cell ()