Sustaining Long-Term Energy Savings for a Major Texas State Agency Performance Contracting Initiative

Abstract

The Texas Mental Health and Mental Retardation agency, now part of the Texas Health and Human Services Commission, was challenged to deal with regularly deteriorating infrastructure at twentythree large campuses located throughout the state during large statewide budget cuts in 2003. Repair and replacement funding was considerably reduced with costs amounting to more than $250 million. The agency therefore decided to take advantage of new state legislation passed in the prior biennium allowing state agencies to use utility savings performance contracting as a means to replace aging and inefficient equipment. In such contracts, the utility savings will pay for the more efficient equipment cost over a fifteen-year period. The utility savings are measured over the life of the contract in order to ensure the savings stream and maintain the savings guarantee. The agency chose an energy services firm specializing in performance contracting. This company uses a utility bill analysis software tool based on cooling degree-days and heating degree-days. To date, savings have accrued for over two years for the first phase of the project and are presented in this paper for one of the measured electric meters. This paper focuses on the on-going savings stream to demonstrate the importance of continued measurement and verification on a representative meter at the Austin State Hospital located in Austin, Texas. In this paper, the Energy Services Company (ESCO) savings results are compared to savings results calculated from a regression analysis software package using average outdoor air temperature data and actual preand post-retrofit data. The software used as the comparison calculates simple mean, two-parameter (2P), three-parameter (3P) change point, or fourparameter (4P) change point models to be used as the utility baseline. To accurately account for the guaranteed savings, it is necessary to apply detailed as well as practical measurement and verification techniques. The agency continues to work closely with the ESCO to generate a savings persistence program that both parties can effectively put into practice; thus ensuring long-term goals are met.