At my alma mater, The University of Texas, here in Austin, Texas, is the Carl J. Eckhardt Combined Heating and Power (CHP) Complex. It is often described:
…as the largest and most integrated microgrid in the U.S…. [It] is capable of generating 135 MW (megawatt) power (63 MW peak) and 1.2 million lb/hr (pounds per hour) of steam (300,000 peak).
I mention all this because the microgrid controller is powered by Emerson’s Ovation distributed control system. Combined Cycle Journal magazine has an article, Real-time optimization pushes out into distribution networks, that highlights a presentation given last year at the Ovation Users Group conference by members of the UT-Austin staff.
This 90-year-old powerplant has been undergoing a series of modernization projects to increase efficiency and reliability of the complex. The most recent optimization project, to not exceed the campus-wide 25MW peak demand charge and maintain a net-zero interface with city of Austin electrical power grid, included:
…the upgrade of the Ovation Electrical Control Energy Management System (ECEMS), dozens of hardwired sensors, and a new chilled-water storage tank. The ECEMS replaces manual control of the four major electrical tie-lines and regulates the campus grid/municipal grid interface…
This energy management system and Ovation DCS:
…monitors the purchased power during each 15-min demand period. The logic calculates the amount of purchased power (MW) in excess of the demand limit. When this number is greater than zero, it is the responsibility of the generator load-control program and load-shedding program to ensure that the demand limit is not exceeded.
When the campus power plant produces more than required, it can sell the excess power back to the city of Austin.
Real-time internal production costs and current grid market prices are used to constantly balance internal generation, purchased power, and power sales.
From an electrical load shedding perspective:
…the ECEMS monitors hundreds of discrete load points with the capability to remove load in less than 100 milliseconds (ms).
Read the article for more on how the UT-Austin team also optimizes the chilled water grid, controls the grid frequency to match the city’s grid, and uses the energy management system to monitor and troubleshoot utility flows.
As the number of microgrids grow and get integrated with the surrounding electrical power grids, microgrid controllers and energy management systems can provide real-time optimization to provide efficient and reliable operations.
You can gain insights from peer members in the power industry and from Ovation DCS experts by registering for the July 29-August 2, 2018 Ovation Users Group Conference and/or participating in the Power and Ovation groups in the Emerson Exchange 365 community.