AC efficiency and direct sunshine
Solar gain in the cooling fins is negligible. Air temperatures in the sun and in the shade are not substantially different if there's any breeze at all, and as soon as the fan starts up the fins reach operating temperature regardless of initial temperature. Ongoing solar gain is minor compared to the overall heat transfer taking place through condensation of the refrigerant. 

More important is access to a fresh air supply so recirculation is minimized, and you could always install a sun screen or small pergola if you think otherwise. 

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