Based on my calculations, at my latitude (40 degrees North), you would need about 16% more panels to generate an equivalent amount of energy per year. This isn't taking into account potential issues with snow buildup (which theoretically would be worse with flat panels) or the effects of cooling (which theoretically could be better due to contact with a thermal sink, the ground), but it's probably pretty close. Even if 20% more panels are required, that means capital costs are superior as long as panel costs are less than 5x racking material and labor costs. Currently panel costs are more like 3x racking costs and will probably continue to decline. Racking costs will probably not go down unless steel prices go down pretty significantly. The only thing that surprises me is that there are not more companies doing this. Perhaps there are factors that neither Erthos nor I am properly considering, but I think this is how most utility solar projects will be done in 5-10 years.

We put in 40 KW and in the racking was a nightmare. The government required soil analysis, reinforced racks, and cement pilings 4 ft deep. Probably could have put in double the panels if we didn't have to deal with the f*** racks

I think this approach has interesting applications for small-scale solar in rural environments if the permitting can be streamlined

I mean with erosion, flooding, and the like, I'm not sure this sort of mounting on the ground would be any less of a hassle...

Most of those things seem nonissues in desert climates with flat Terrain.

steel prices are probably not a significant component of racking prices; scrap steel costs 50¢ a kg

the numbers they gave make the pv module prices seem slightly higher than the cited racking prices (15¢ per watt) but it's a little hard to be sure because of the numerous kinds of watts involved