Otto Van Geet is a principal engineer at NREL. Van Geet has been involved in the design, construction, and operation of energy-efficient research facilities such as laboratories and data centers, office and general use facilities, and low-energy-use campus and community design. Van Geet was one of the founding members of the Labs21 (Smart Labs, I2SL) program and provides technical guidance for the program. His experience also includes renewables screening and assessment, PV system design for on- and off-grid applications, energy audits, and minimizing energy use. Van Geet has authored many technical reports and conference papers and been recognized with many awards from professional associations, including the 2007 Presidential Award for Leadership in Federal Energy Management, the 2011 GreenGov Green Innovation Presidential Award for the NREL Research Support Facility data center, and the 2022 International Institute for Sustainable Laboratories (I2SL) Lifetime Achievement Award.

He lives with his family in a zero electrical energy off-grid passive solar house with a 4 kW PV/hybrid power system and solar water heating that he designed and built 27 years ago.