AbstractThis paper investigates the feasibility of using fixed resistors instead of active maximum power tracking as electrical loads for long‐term exposure testing of photovoltaic modules and arrays. The method of investigation was to compare resistive versus active loading on two modules for which historic current‐voltage data over time were available. Also, a small amorphous silicon array was installed with a resistive load and the performance has been monitored versus time. The major conclusion of this work is that fixed resistive loading is an inexpensive and viable means of loading photovoltaic devices for exposure testing if the resistance value used is close to the ratio of the voltage to the current at the maximum power point under Standard Test Conditions. Copyright © 2006 John Wiley & Sons, Ltd.