It's 9.5 square miles. 6080 acres. Even in California scrub land isn't going to cost $10,000 an acre, so the land costs of the US project shouldn't exceed $100 million.

(for example, here's a much larger area in the same county for $35 million: http://www.landwatch.com/San-Luis-Obispo-County-California-F... )

edit: tack on another couple hundred million for power line easements and you still haven't explained all that much of the cost difference. And I really doubt that they spent anywhere near $300 million on land and easements.