3M PV300: A 300 kW single crystal silicon concentrating PV system was installed in 1990 on the roof of a
parking structure at a commercial research facility outside Austin, Texas. This is a 22X linear Fresnel lens concentrator system with a total array aperture area of 2006 m2. The modules are mounted on two-axis (tilt-roll) trackers. A view of this system is shown in Fig. 7. Two 150-kW inverters are used to connect the PV system output to the electric distribution system. Excess output over the parking structure's requirements is fed to the City of Austin's distribution system. The measured and design ac ratings
are 248 and 273 kW, respectively, for operation at 60˚C with 1-kW/m2 input. The objective of this project is to examine the capabilities of larger PV systems for demand side management of customer loads. During the last six months of 1990, this system generated 170500 kWh (a.c.) and had a downtime of 258 h, primarily due to inverter problems and water intrusion into modules causing ground faults (see [25]).