Renewable Energy

Oakdale Renewable Energy Plant


Grand Place Award, Energy Production Category, for Engineering Excellence from the American Council of Engineering Companies (ACEC), 2013
Top Plant, POWER magazine, Sept. 2012
National Recognition Award for Engineering Excellence from ACEC, March 2012
UI receives $25,000 grant to study biomass fuels for campus power plant, March 2012
Engineers receive $951,500 federal grant for UI green power initiative, UI press release, July 23, 2010


The goal is to operate the UI Research Park campus on 100% renewable energy

What is the Oakdale Renewable Energy Plant?
The Oakdale Renewable Energy Plant (OREP) is a series of projects whose purpose is to demonstrate multiple technologies, using locally available renewable fuel sources, to meet the energy needs at the UI/Oakdale Research Park (Oakdale Campus).

How were the utility needs of the UI/Oakdale Research Park being met?
The Research Park has traditionally been served by a natural gas (fossil fuel) fired boiler plant that supplies steam for building heating, ventilation, and air conditioning (HVAC), and by purchased electric power from the grid (mostly generated from coal).

Why was there a need to modify the existing plant?
The existing utility system dates to the 1960’s, and has limited capacity for expansion. With the construction of major building projects (e.g. Hygienic Lab, Data Center, Environmental Management Facility), it is necessary to install new utility infrastructure to serve these loads. These new load requirements provided an opportunity to install modern Energy Production systems with high efficiency, rather than just expand the existing system. It also provides central backup electric power (versus individual building diesel generators) to critical infrastructure, such as the Hygienic Lab.

The project does not replace all existing utility infrastructure on the UI/Oakdale Research Park campus; three natural gas boilers and the steam distribution system remain. The gas boilers will serve a peaking and backup role, and the steam distribution system will continue serving existing connected loads.

What technologies are being used?
TThe Oakdale/UI Research Park campus Energy Production system includes two gas fired internal combustion engine generators with heat recovery, a wood chip boiler, a central chilled water plant, and three natural gas boilers.  The electric system is capable of operating in island mode, or in parallel with the grid for load management.  When operating in CHP mode, the system operates at an overall efficiency of 80%.

The following table illustrates the technologies being installed, their advantages, and the status of the projects.




Two 1,400 kW reciprocating internal combustion engine generators, with heat recovery.

Can be powered from natural gas or low-Btu gas (e.g. landfill gas). Exceptionally high efficiency, when compared to separate generation of heat and electric power.

Operational on natural gas. Supplies hot water, versus steam, for HVAC thermal loads in new buildings.

Landfill gas project

Provides renewable energy to operate the reciprocating internal combustion engines, providing campus electric power and thermal energy from renewable energy.

Negotiating agreements for gas supply, transportation, cleaning and compression. Pipeline between City of Iowa City landfill and OREP required.

Central hot water distribution system

More efficient, compared to steam, for distributing thermal energy to HVAC loads.

Operational to the Environmental Management Facility and Information Technology Facility.

Central chilled water distribution system

Enables use of a large, efficient central plant for cooling, versus individual building chillers.

Operational to the Environmental Management Facility and Information Technology Facility.

Central chilled water plant

Able to produce chilled water for building HVAC loads in a more efficient central plant, versus individual building chillers. Reduces amount of building space and equipment for HVAC.


Biomass boiler

Replaces one natural gas boiler with a solid fuel (e.g. wood chips, oat hulls) biomass boiler.


Research gasifier

Installs a small gasifier for College of Engineering to research and determine combustion characteristics of various renewable alternate fuels (e.g. expired seeds, corn stover, and paper sludge).

Construction and commissioning completed. Fuel produced in the gasifier will be burned in the biomass boiler, through a special burner.

New electric substation

Provides a larger capacity and more reliable connection to the grid.

Substation installed and operational.

New buried electric distribution system

Underground electric service much more reliable, compared to overhead electric lines.

System installed and serving new loads, existing overhead lines will be phased out in future years.

How will the OREP serve as an innovative model?

  • Identify and demonstrate the feasibility of using locally available renewable energy.

  • Provide research, education, and training opportunities for University faculty and students, as well as industry and the general public.

  • The College of Engineering will collaborate with UI’s Utility Enterprise in pursuit of academic goals, to be achieved concurrently with energy production.

  • Local natural gas and electric utilities will remain connected to the Oakdale utility system to provide emergency back-up service and a market for excess renewable electric energy generated above campus requirements.

For more information, contact: Steve Kottenstette.