Landmark Northwest study reveals smart grid pros and cons

Monday, July 20, 2015

From the July 20, 2015 issue of Public Power Daily

Originally published July 17, 2015

By Elisa Wood, Contributing Writer

A recently completed $178-million Pacific Northwest Smart Grid Demonstration Project led by Battelle demonstrated that smart grids are more efficient and resilient, according to a project report. The demonstration project was the largest of 16 smart grid demonstration projects funded by the U.S. Department of Energy under the American Recovery and Reinvestment Act of 2009.

The effort encompassed more than 60,000 metered customers, many of them served by public power utilities in Idaho, Montana, Oregon, Washington and Wyoming. The project tested 55 different technologies at 11 test sites and generated 350 billion data records that can serve as a basis of further research.

The results are reported in an 840-page document that examines work with smart meters, demand and load curtailment technologies, energy storage, voltage controls, a first-of-a-kind transactive coordination system and other utility smart grid applications. “As one of the nation's largest and most complex smart grid demonstration projects to date, the Pacific Northwest Smart Grid Demo experienced much success, while also identifying many opportunities for growth," said project director Ron Melton of Battelle, which led the effort on behalf of the region and the Department of Energy, which provided funding.

The centerpiece was a hypothetical demonstration of transactive coordination, the automatic buying and selling of power based on events that influence electricity prices. The system is meant to reduce peak demand, costs, and the challenges of integrating intermittent renewables. Using technology developed by Pacific Northwest National Laboratory, and a model grid provided by Alstom, the system sent signals every five minutes to utilities. The signals provided current and predicted prices and availability of power.

The hypothetical system partitioned the Pacific Northwest into 27 power nodes, where information could be sent and received. Each node communicated the pricing and exchange information with its nearest neighbor. When the signals predicted peak power demand, and therefore high costs, the smart grid technologies kicked in to reduce consumption.

The demonstration took place on a mock grid that reacted to real grid events. The final analysis showed the transactive system came through when two critical events occurred on the actual grid. In one case, a nuclear plant experienced an unplanned outage, cutting the plant’s available capacity by about half. In another case, a sudden burst of wind peaked generation to 2,884 MW. "Dramatic events such as these wouldn't normally be on the radar of individual utilities, but can significantly impact utility operations," Melton said.

Transactive demand response could lower the Northwest’s peak demand by 7.8 percent if 30 percent of the regional electric grid used the equipment, according to an IBM simulation. The modeling also indicated that transactive coordination could lower the Northwest's overall power costs by using wind energy when abundance is high and cost low.

Several other aspects of smart grid — from behavior change to distribution technology additions — were demonstrated by public power utilities and others that participated in the project, among them:

  • Benton Public Utility District in Washington used advanced meters and energy storage to prevent or quickly address outages and to control voltage.
  • Ellensburg, Washington added 153 kW of renewable energy and tested a remote recloser switch to quickly disconnect renewables from the distribution system to prevent over-generation on the grid.
  • In Montana, Flathead Electric Cooperative recruited customers to a ‘peak time’ program that used smart meters, in-home displays, and demand response (including appliances) to reduce energy use.
  • Idaho Falls Power tested more smart grid assets than any other utility in the study. The Idaho municipal utility demonstrated voltage management, power factor control, distribution automation, water heater control, thermostat control, in-home displays and storage with plug-in hybrid electric vehicles, solar, and battery.
  • Lower Valley Energy, a Wyoming electric cooperative, tested member interaction with advanced metering and in-home displays. It also tested static VAr compensator, renewables, and battery energy storage as a means to defer infrastructure upgrades.
  • Milton-Freewater, a city in Oregon, demonstrated demand response units on water heaters and space conditioning equipment, dynamic distribution voltage management, voltage-responsive, grid-friendly demand response units, and static conservation voltage reduction
  • Peninsula Light Company focused on reliability concerns for Fox Island, Washington. The island is served by two distribution circuits. With load growing, the project focused on ways to reduce stress on the system, including installation and evaluation of demand-side management using load control modules, conservation voltage reduction with end-of-line monitoring, and dynamic distribution automation.

The study noted several lessons learned and paths for future research, including better preparedness by utilities for the onslaught of data they receive from smart grid equipment. The project also unearthed a need for more compatibility and standardization of equipment, so that technologies can work together. And the final analysis noted a need for more market stability and product maturity, as well as increased public involvement.

A report summary is here and the full technical report here.