PNW Smart Grid Demonstration Project

Electric Grid Stability

Smart Grid >> Grid Stability Support

One major focus of the SGDP is to investigate the use of regional resources to help maintain a stable electric transmission grid (Grid) during upset conditions, including sudden loss of renewable energy generation (wind, solar, etc.). One cause of Grid instability occurs when the on-line electrical generation capacity falls below the electrical load connected to the Grid, and can result in brown-outs and/or power outages.

Historically, the Grid Operator coordinates with Utilities and Power Producers to assure sufficient reserve generation is on-line to cover anticipated load swings as the load goes up and down during the day. However, the addition of renewable energy (solar, wind, etc.) generation which can’t be controlled or scheduled introduces a very significant change and the historic operating methods may not be sufficient. Other “tools” may be necessary to maintain Grid stability so the SGDP is investigating the use of regional resources, called “assets”, as an additional “tool”. The regional assets include local Generator dispatch and Load Sheds that occur in response to a Transactive Signal sent by the Grid Operator. Load sheds are any process that turns off or reduces the energy required for a given system or device, resulting in less electrical load on the Grid.

WSU will utilize five “assets” in support of that objective. The first two WSU “assets” are Load Sheds, a Chilled Water Load Shed where the campus chiller electrical load is reduced by increasing the output from our chilled water Thermal Storage Tank, and an HVAC Load Shed in which the air flow and related fan electrical loads in selected non-lab areas are reduced for short time periods. The HVAC Load Shed feature also allows implementation of energy-saving Low Occupancy (evening/weekend) HVAC load reductions.

The other WSU “assets” are three generators at our Grimes Way Steam Plant (GWSP). These generators can be operated in parallel with the Grid, supplying some of the WSU load and thereby reducing the total WSU load on the Grid.

During the SGDP Test Period from September 2013 through late 2014, the Transactive signals will be generated by Battelle/PNNL and sent to each of the participating Utilities. In response to a Transactive signal, Avista Utilities may send an Avista Generated Request Signal (AGRS) to WSU requesting one or more of the WSU “assets” be activated. The AGRS request(s) will be evaluated by the WSU Dispatch Center and/or the GWSP Steam Engineer and the requested asset activated unless a situation exists which prevents activation of the asset(s). WSU’s response to an AGRS is automatically sent to Avista indicating the asset activation will occur or the reason that activation is not possible at present.

WSU Benefits
  • Contributing to the successful integration of Renewable Power sources into the Transmission Grid supports the WSU commitments on renewable energy, sustainability and carbon neutrality
  • WSU’s reputation as a strong Electrical Power Systems academic and research institution is enhanced by the real-world application of smart grid measures on the campus systems
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