Staff Biographies


Energy Efficiency

CEODennis R. Landsberg, PhD, PE, CEM, CDSM, LEED® AP, BEAP, CP EnMS – Industrial
PresidentRon Slosberg, CEM, LEED® AP, BOMA
Vice PresidentBrendan Kelly, PE, LEED® AP, CEM, CGI
Vice PresidentYigit Guctas, CEM, CDSM, DGCP
Senior Energy EngineersBrian Martz, CEM, CMVP
Michael Stiles, PhD, CEM
Energy Engineer IIDanielle McGrath, EIT
Energy Engineer ISean M. Wertheim
Energy Engineer IAhmani Roman
Energy AnalystPaul Remington, CEM
Energy AnalystMichelle Wooddell

Name: Dennis Landsberg, Ph.D., P.E., CEM, CDSM, LEED®, ASHRAE BEAP, CP EnMS – Industrial

Title: CEO
UntitledDr. Landsberg has over 39 years of experience in energy efficient building technologies, building energy analysis and audits, energy consumption, demand-side management, commissioning and energy conscious building simulation and design. His building end-use metering applications include DSM impact evaluation, RD&D applications for buildings and alternate fuel vehicles and building energy simulations. Dr. Landsberg has also provided expert witness testimony with regard to performance of energy conservation systems and programs. Services included development of energy program workbooks, training seminars and demonstration projects for energy efficient technologies. Dr. Landsberg has been providing Monitoring and Verification services for his entire professional career. Projects have included utility and government R&D projects, energy conservation program R&D projects and ESCO review services.

Dr. Landsberg currently serves as Chairman of ASHRAE TC7.6 – Building Energy Performance and ASHRAE Guideline 14 – Measurement of Energy and Demand Savings. Dr. Landsberg is also a voting member of ASHRAE Standards Committees SSPC 100 – Energy Efficiency in Existing Buildings, SPC 211 – Building Energy Audits, SPC 105 – Standard Methods of Determining, Expressing and Comparing Building Energy Performance. He was also the lead author of ASHRAE’s Energy Efficiency Guides for Existing Buildings.

Dr. Landsberg has been responsible for conducting hundreds of energy audits including preparation of work scopes, gathering data in the field, energy analysis and report preparation. The measures analyzed have included industrial process improvements, anaerobic digestion, wind, photovoltaic as well as building energy efficiency improvements. He has led numerous commissioning, retro-commissioning and LEED commissioning studies. Projects have included data centers and combined heat and power. He has also managed numerous modeling projects for new construction.


Name: Ron Slosberg, CEM, LEED®, BOMA

Title: President

2Over the past twenty years, Mr. Slosberg has provided comprehensive energy efficiency, energy procurement, distributed generation, and energy management evaluation, assessment, and implementation consulting services. Mr. Slosberg has completed over one hundred comprehensive energy efficiency and technology assessment projects. He has been a principal consultant on forty energy savings performance contracts providing services such as RFP development, measurement and verification, savings guarantee review, contract negotiation, and technical review. Mr. Slosberg has provided training presentations on numerous topics including energy performance contracts and the utilization of life-cycle costs methods.


Name: Brendan Kelly, P.E., CEM, LEED® AP, CEM, CGI

Title: Vice President

4Brendan received his AAS in Air Conditioning Engineering Technology from Canton College of Technology and his BS in Mechanical Engineering from SUNY Utica Institute of Technology. He has been with L&S Energy Services since its inception.

Brendan is experienced in performing and directing energy audits and surveys of multifamily, commercial, industrial and institutional buildings. He is skilled in the area of building simulation modeling, data acquisition systems, monitoring equipment installation, data analysis and end use energy conservation measure analysis. He has managed many technical assistance and evaluation projects for small commercial, municipal, large commercial and industrial clients for both existing buildings and new construction projects.

Additional certifications include NYSERDA’s Hydronics for High Efficiency Biomass Boilers and ICC Commercial Energy Inspector.


Name: Yigit Guctas, CEM, CDSM, DGCP

Title: Vice President

5Yigit Guctas received his Chemical Engineering degree from Istanbul Technical University in 1999. He has over 22 years of experience as an energy engineer, managing engineering teams and projects. He is an expert in energy assessments of residential multifamily, commercial, municipal, industrial, educational, and institutional buildings.

Mr. Guctas has served as a subject matter expert in the development of the Multifamily Audit Technical Guidelines developed by the Oak Ridge National Laboratory (ORNL) for the US Department of Energy (DOE). He has served as a committee member for City of Schenectady, NY Energy Advisory Committee between 2012 and 2015, President of Association of Energy Engineers (AEE) New York Capital Region Chapter in 2012, 2015, and 2016, and served as the co-chair of Town of Glenville, NY Efficiency in Government Committee between 2016 and 2023, helping the Town of Glenville realize the benefits of effective strategic planning.

He is currently a member of the Building Performance Institute (BPI) board of directors, and he has been a part of the BPI Multifamily Standards Technical Committee since 2016, helping in development of BPI-1105 -Standard Practice for Multifamily Energy Auditing. He is currently serving as a subject matter expert for the revision of ANSI/BPI-2400-S-2015.


Name: Brian Martz, CEM, CMVP

Title: Senior Energy Engineer

6Brian joined L&S Energy Services in the spring of 2012. He received his MBA from Sage Graduate School and his BS in Energy Engineering Technology from RIT. He has been involved in the energy management field for over twenty-five years, serving the small commercial, educational, municipal and industrial markets. Brian has broad-based experience in consultation, system design, account management, energy savings feasibility, technical assistance, energy system commissioning, energy auditing and energy savings performance measurement and verification. He has worked as a design engineer, utility company energy utilization specialist, development/energy engineer, energy performance assurance engineer and technical reviewer.


Name: Michael R. Stiles, Ph.D., CEM

Title: Senior Energy Engineer

7Dr. Stiles has worked with energy-efficient technologies for 25 years. His fields of expertise include building science, renewable energy systems, solar optics and intellectual property development. He joined L&S Energy Services in October, 2013.

Mike’s building science activities began with projects sponsored by the US Department of Energy, the NYS Energy Research and Development Authority, the Electric Power Research Institute and other organizations. During this time, he participated in nationally-based R&D and technology transfer in the areas of weatherization, building monitoring and simulations, convective pathway analysis, residential appliances, indoor air quality, statistical measurement and verification techniques and energy auditing. A significant part of these efforts was spent in the field working with practitioners at the cutting edge of expertise. He has conducted training in several of these areas, published extensively and periodically gives professional presentations.

Dr. Stiles has extensive experience in solar technologies and daylighting. He holds three US patents in these fields. His latest interest is the development and deployment of extremely efficient greenhouses.

Mike’s current work at L&S Energy Services include peer review of energy audit reports for NYSERDA, building systems analysis, statistical analysis of energy projects and energy audits. He is certified in NYSERDA’s high-efficiency biomass boilers program.


Name: Danielle McGrath, EIT

Title: Energy Engineer II

Danielle received her BS in Mechanical Engineering with a concentration in sustainability and MS in Mechanical Engineering from Binghamton University.

She has completed academic life cycle studies for alternate energy generation methods and energy-related research and simulations. Danielle also has experience in the utility industry, as well as transportation and construction.

At L&S, Danielle performs energy audit report reviews, energy efficiency analysis, aides in the development of energy models in eQuest and more.


Name: Sean M. Wertheim

Title: Energy Engineer I

11Sean received his B.S. in Integrated Science and Technology with a concentration in Energy from James Madison University in May 2023 and joined L&S Energy Services following the completion of his undergraduate studies. He has completed several energy audits as an Energy Analyst Intern the summer prior to joining L&S.

At L&S Energy Services, Sean will be conducting energy audits and energy efficiency analysis.


Name: Ahmani Roman

Title: Energy Engineer I

11Ahmani received his BS in Applied Physics from Siena College and MS in Mechanical Engineering from Clarkson University. He has experience in solar technology and construction.

At L&S Energy Services, Ahmani will be conducting energy audits, energy efficiency analysis, and aiding in the development of energy models in eQuest.


Name: Paul Remington, CEM

Title: Energy Analyst

11Mr. Remington has been in the energy field since 1981 and with L&S Energy Services since its inception. He received his AAS in Construction Technology from Hudson Valley Community College and is an active member of the Association of Energy Engineers and ASHRAE.

Mr. Remington is experienced in performing and directing energy audits and surveys of residential, commercial, industrial, institutional and agricultural buildings. He is skilled in data acquisition systems, monitoring equipment installation, data analysis and end use energy conservation measure analysis. He has personally performed over 1,000 energy audit surveys.


Name: Michelle Wooddell

Title: Energy Analyst

Ms. Wooddell has been with L&S Energy Services since its inception. She received her BA in Political Science from Fordham University. She has many years of experience in project administration/management, information technology and customer service.

Ms. Wooddell manages L&S’ team for Green Jobs Green New York Energy Studies. She coordinates the annual NYC LL84/LL133 Benchmarking of approximately 185 multifamily buildings in New York City. She administers Agriculture Energy Audits assigned by NYSERDA, assists with proposals and marketing/outreach activities and provides administrative support for the entire staff of L&S Energy Services.


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