Patent ID: 8620632

Claim:
A method of determining heat transfer parameters of a portfolio of existing buildings, comprising: generating dynamic equations describing heat and moisture transfer through building envelope; generating a static heat transfer model by transforming the dynamic equations, the static heat transfer model generated by integrating the dynamic equations over a time period covering a season; quantifying all terms for the generated static heat transfer model based on energy usage data associated with the existing buildings over the time period, dimension information associated with the existing buildings, data associated with one or more characteristics of the existing buildings, temperature information during the time period, and humidity information during the time period; estimating, by a processor, coefficients of the terms by fitting calculated energy usage with the observed energy usage over multiple time periods, the estimated coefficients representing aggregated quantities of multiple physical properties of the building envelope; clustering the existing buildings into two or more clusters of buildings based on a physical similarity associated with one or more characteristics of the existing buildings; developing a regression model for each of the clusters of buildings, the regression model describing how the aggregated quantities mathematically depend on the multiple physical properties of the building envelope; and estimating individual heat transfer parameters associated with individual components of the building envelope based on the regression model and the estimated coefficients representing aggregated quantities of multiple physical properties of the building envelope.