American construction costs are unique in the world. No other country is even in the same ballpark - this includes wealthy countries (Spain, Singapore, Hong Kong, Italy) with plenty of safety rules. Delhi's construction costs are typical, they are not exceptionally low.
https://pedestrianobservations.wordpress.com/2013/06/03/comp...
https://pedestrianobservations.wordpress.com/2011/05/16/us-r...
I just bring up Delhi because a) the article is discussing an Indian solar project and b) I have a Delhi metro card in my wallet and am pretty familiar with it.