Key Auditing Staff

Our senior engineers have been conducting energy audits for over 15 years and have P.E.s and/or CEMs.  Abraxas has conducted hundreds of energy audits and retro-commissioning studies.


john-avina-president John Avina, CEM, CMVP, President of Abraxas Energy Consulting, has worked in energy analysis and utility bill tracking for 18 years. During his tenure at Thermal Energy Applications Research Center, Johnson Controls, SRC Systems, Silicon Energy and Abraxas Energy Consulting, Mr. Avina has managed the M&V for a large performance contractor, managed software development for energy analysis applications, created energy analysis software that is used by hundreds of energy professionals, taught over 250 energy management classes, created hundreds of building models and utility bill tracking databases, modeled hundreds of utility rates, and performed and managed energy audits and retro-commissioning of over 15 million square feet of building stock. Mr. Avina has a MS in Mechanical Engineering from the University of Wisconsin-Madison. In 2010, the Association of Energy Engineers recognized Mr. Avina’s work with the Energy Professional Development award for Region 5.
IMG_8688 Ertun Reshat, CEM has more than 17 years of energy engineering experience. Prior to joining Abraxas Energy Consulting, he worked over 3 years with AECOM and over 4 years with Johnson Controls. With extensive training and experience in the energy auditing and project development, Mr. Reshat served as a senior engineer for AECOM providing IGAs and Level 2 audits and developing projects for California State University-Chico, California State University-San Marcos, and many more. For these two projects, he led the audit and savings calculation efforts for all HVAC and water systems measures. Overall, he has successfully completed more than 150 commercial and industrial combine energy audits throughout his career. At Onsite Energy, he specialized in providing measurement and verification of energy savings He is proficient in data collection and real time monitoring systems for low and high voltage equipment. Having seen projects go through the entire process, he brings with him a practical knowledge of what works and what does not work, and an understanding of problems that can be avoided.
IMG_8688 Steve Rottmayer, P.E., LEED AP has been working in the energy efficiency field for over 15 years and has led energy assessments in over a hundred buildings, including scoping-level walk-through assessments, detailed energy studies and retro-commissioning analyses. Many of his energy-efficiency projects included start-to-finish implementation that culminated with measurement and verification of the achieved energy savings. He specializes in energy audits, retro-commissioning, design-build scope of work development, design review, construction assistance, field data collection and measurement and verification. He conducted energy assessments for a variety of customers including the SFPUC, PG&E and Alliant Energy. Mr. Rottmayer has worked with all parties involved in retrofits such as company energy managers, building property managers, building operations and maintenance staff, design engineers, contractors and utility representatives.