A study released by the Copenhagen Economics looks into the relation between house prices and energy ratings based on an econometric analysis of 365,000 sales of single-family houses in Denmark from 2006 to 2014 and a number of controlled experiments on both potential buyers and real estate agents. The study concludes that there is a clear correlation between high energy rating and high sales price. However, energy rating is not yet fully reflected in the sales price: indeed the higher sales price induced by a higher energy rating is not as high as the saved future energy cost over time would justify.
The study titled “Do homes with better energy efficiency ratings have higher house prices? (Econometric approach) can be downoladed here