Jun Nabara, who works in the Japanese solar industry, just tweeted (in Japanese) that some of the new Japanese solar projects pay between 4 and 8 yen per kWh for the costs of the land they use. That is one possible explanation for the high feed-in tariff for solar in Japan. And it is a good reason to use land in the Mongolian Gobi desert for large scale generation rather than expensive land in crowded Japan.
Update: Nabara kindly answers with this tweet (in Japanese) and clarifies that different projects have different levelized costs of energy, and the relative weight of land costs are less in many projects.
Still, 4 to 8 yen a kWh is quite remarkable, and it would be essentially zero in the Gobi desert.