This sounds wrong, but it is not. There are installation costs associated with PV arrays that are nearly independent of the efficiency and depend ONLY on the area of the array. These costs always exceed the cost of the PV arrays themselves.

1. The arrays must be mounted on a sturdy structure.
2. The arrays need protective covering.
3. The arrays need washers and wipers like car windshields to remove dust and grime.
4. The arrays must be tied together with wiring harnesses and electrical controls.
5. For maximum utility, the arrays should be turned to face the Sun during daylight hours. This adds to mounting costs.
6. PV arrays need LAND area of some sort, even if mounted on buildings, there is only so much area that a given building can host.

In addition to those mentioned above, PV arrays also need storage, which, although independent of area, is quite large. Storage is costly, and also is unlikely to be more than 70% efficient: 100 joules in give 70 joules out, at most.

Some newer experimental cells have broken the incredible 50% efficiency barrier. At almost any cost per area, they will be cheaper, when mounted, than lower efficiency units.

The biggest problem with PV is that it only works during daylight hours. (Forget the power satellite that beams power to Earth in microwave form. It would be cheaper and more efficient to put billions of hamsters into spinning cages with tiny generators than to beam power from a satellite.)

David F Mayer