Oncor launches paradigm-breaking microgrid in Texas

The nature, shape and form of an emerging 21st century model for U.S. electric utilities is now on display outside the town of Lancaster, Texas. It's there, in a comparatively remote area of southwestern Dallas County that Texas electric utility Oncor and smart grid specialists S&C Electric and Schneider Electric have assembled a “proof of concept” version of what they contend is “one of the most advanced microgrids in North America.

“Engineered to maximize newly installed energy storage, renewable generation and improve reliability,” the smart microgrid now up and running at Oncor's System Operating Services Facility (SOSF) encompasses four interconnected microgrids that make use of nine different distributed generation sources. These include two solar PV arrays, a microturbine, two energy storage units and four [diesel] generators,” S&C explains in a press release.

Oncor's smart microgrid highlights the speed at which innovative companies and new energy technologies are shaking up the highly regulated U.S. power industry and markets. “Breaking the mold” that has come to define “culture” among U.S. utilities, Oncor is betting that the mix of innovative renewable and conventional energy generation, energy storage and distribution technology it has introduced will help blaze the trail towards an organizational, regulatory and industry-wide transformation.

Breaking the Mold

Oncor's smart microgrid is of strategic importance for the electric utility as it seeks to transform the organization into an agent of change and promote regulatory reforms that would open the door for Texas utilities to own and operate energy storage systems. Last November, Oncor, which serves some 10 million customers, announced it intended to seek state regulatory approval to deploy as much as $5.2 billion worth of distributed grid-connected energy storage capacity beginning as early as 2018.

Oncor has already invested in building new transmission lines that now bring vast amounts of electrical power to Texas consumers from wind farms in West Texas. Some 3,500 miles of new transmission lines have been installed across Texas's Competitive Renewable Energy Zone (CREZ). “Oncor estimates that annual power prices have declined by $2 billion statewide thanks to CREZ and other improvements,” Dallas Morning News' Mitchell Schnurman reported in a May 31, 2014 article.

Moving extremely quickly to bring the Oncor's microgrid up and running, project partners took just six months to construct an initial test version of the system. It took just nine months to complete the entire microgrid — a veritable “blink of an eye” in utility-time, S&C Director of Business Development David Chiesa told REW in an interview.

The smart microgrid's generation assets consist of:

• a 106-kW solar carport PV array;
• an 8-kW ground-mounted PV array;
• a 65-kW microturbine that runs primarily on propane (for reasons of cost and availability);
• two 175kW diesel generators;
• a 45-kW gas reciprocating generator;
• a 25-kW/25-kWh S&C PureWave CES Community Energy Storage unit;
• a 200-kW/400-kWh Tesla Li-ion batter storage unit.

In addition to S&C and Schneider Electric, Axiom handled the microgrid's solar PV arrays and Capstone provided the microturbine. Prim Construction LLC served as the general contractor and Horizon the electrical contractor for the project, which entailed constructing a new environmental services facility, part of which is Oncor's Technology Development & Education Center, or TDEC, Chiesa recounted. Open to the public, the actual components that make up Oncor's are on display for viewing. A Star Trek-like bridge, or command center simulates the microgrid's operations.

The “State of the Art” in Hybrid Microgrids

An automated distribution schema and technology developed by S&C and Schneider optimizes operations across all four of the system's component microgrids. As S&C elaborates: “Schneider Electric's DSO (Demand-Side Operations) model delivers economic optimization and dispatch of the microgrid distributed energy resources (DER), allowing the system to maximize renewable energy usage and storage while minimizing energy costs.”

Oncor's smart microgrid platform enables each of the four component microgrids to operate independently. That's a key attribute in terms of enhancing utilities' ability to identify and respond to failures anywhere across the microgrid system. In effect, the smart power generation and distribution platform can self-diagnose, isolate and reconfigure the entire microgrid system in the event of breakdowns or failures in any one of the microgrid platform's component parts. Moreover, “it does all of this in a matter of seconds, or faster than a customer could find their flashlight in the dark,” Chiesa highlighted.

Li-ion batteries from Tesla and S&C provide the microgrid's energy storage capacity according to specifications set out by Oncor. Tesla is beating the competition when it comes to the price of Li-ion battery storage, Chiesa pointed out.

“Tesla is a real power in the marketplace on price terms,” he commented. Though rated at 200kW-400kWh the Tesla Li-ion battery unit installed as part of Oncor's microgrid actually functions within a relatively tight operating band of between 90kW-180kWh, which met Oncor's specs. Chiesa added that he hasn't see Li-ion battery prices under $500 per kWh as yet. If they dropped down to the $350-$300 per kWh range it would make a huge difference to microgrid and energy storage project economics, he pointed out.

Summing up Oncor's microgrid and its efforts to advance use of cleaner, more sustainable and renewable new energy technologies, Chiesa said: “Improving power reliability and optimizing generation assets requires disruptive technologies that allow customers to work on and off the grid. Oncor’s microgrid is showing the world how utilities can help their communities in the future.”

http://www.renewableenergyworld.com/rea/news/article/2015/04/oncor-launches-paradigm-breaking-microgrid-in-texas