Sandra Ringelstetter Ennis

Chief Operating Officer
Senior Managing Director


Tel: +1 312 573 2823
Fax: +1 312 573 2810

Email: sandra.ringelstetter@nera.com
vCard: Download


MS in industrial engineering-operations research, University of Wisconsin
BS in industrial engineering, University of Wisconsin


Sandra Ringelstetter Ennis oversees NERA's global operations, including business development, growth strategies, increasing efficiency across all aspects of operations, and the company's worldwide offices. Based in NERA's Chicago office, Ms. Ringelstetter Ennis is a member of the firm's Management Committee and Board of Directors.

Ms. Ringelstetter Ennis has been involved in the energy industry for over 25 years as a consultant and expert specializing in wholesale electricity markets, asset valuation, and the modeling of electric systems. Her expertise includes market assessment, market price forecasting, power plant valuation, financing support, due diligence and transaction support, emission analyses for New Source Review (NSR) compliance, and methodologies and algorithms for the simulation of electric systems.

Ms. Ringelstetter Ennis provides clients with litigation support and expert testimony for coal-fired generators in Environmental Protection Agency (EPA) and Sierra Club NSR enforcement actions. She has supported several clients through Section 114 requests under the Clean Air Act and performed numerous emission analyses for projects included in Notices of Violation issued by the EPA. She has also assisted clients in developing and implementing a process for ongoing NSR emission analyses and compliance submissions. The foundation of much of Ms. Ringelstetter Ennis' work in the electricity sector is her expertise in the use of market simulation models, coupled with her engineering background and knowledge of power plant operations. She has led large modeling teams in complex consulting and litigation assignments.

In the power generation sector, Ms. Ringelstetter Ennis assists clients in the due diligence, acquisition, and financing of new and existing generating facilities. For both conventional and renewable generation projects, she has prepared independent valuations and market expert reports for internal investment review, offering memorandums, debt financing (including for the Department of Energy Loan Guarantee Program), and capital market bond ratings. She also provides market advisory services to clients regarding the impact of changes in fundamental market assumptions or proposed changes to market rules. Throughout her career, she has appeared as an expert witness regarding market analysis and power plant valuation. She has provided testimony before the US Federal Energy Regulatory Commission, several state commissions, and in arbitration proceedings.

Title Type Author
FERC Order 1000 and Public Policy Transmission Projects Published Article Sandra Ringelstetter Ennis et al.
Setting Up a Compliant Process for New Source Review Published Article Sandra Ringelstetter Ennis