North to Alaska: Project Tests Electrification Concepts

To date, the PNNL-led project has coordinated heat pump installations in three homes in the community, at no cost to owners, with additional installations planned. The units have performed capably, as researchers expected. Rosenberg said one resident planned to use the heat pump during more moderate parts of the year, but instead employed it all winter long, entirely forgoing use of a diesel-powered boiler.

“We know that Cordova is a key test case that can inform many other electrification efforts in rural, cold communities across the nation,” Rosenberg said. “We need to answer a range of questions to achieve broader electrification in the United States, including how electric heat pumps can be operated effectively in colder areas where electricity availability may be constrained.”

A central tenet of the Cordova project has been evaluating “demand response” concepts. Demand response involves automatic communication between heat pumps and the power grid to coordinate electricity consumption in a way that assures there’s plenty of power for everyone, while providing desired levels of home comfort. In any community, as more electric devices come online, this methodology becomes increasingly important.

“Our project has shown that new demand response and communications methods can work. Further, we’ve employed an array of demand response methods that have been used for additional data collection this winter,” Rosenberg said.

Clay Koplin, chief executive officer of Cordova Electric Cooperative, supplier of electricity to the community, began envisioning electrification strategies many years ago, and now he’s living part of that vision.

“As a small, remote microgrid, we spill excess hydropower at times, and at other times we have to supplement generation with expensive diesel fuel. I have been considering demand response and dispatchability for over two decades,” Koplin said. Dispatchability refers to quickly adjusting power generation based on market need.

“I have also been monitoring ground source heat pump technology for over 30 years, but it is a much more expensive alternative than the newer air source heat pumps deployed by PNNL, which I realized immediately could add value as a demand response asset,” he added.

Unique factors at play in Cordova

Some might ask why only three heat pumps have been installed over the past year. Researchers wanted more installed, and the electrical cooperative and many homeowners remain excited about the prospect of electrification. But there have been complications.

Early on, Rosenberg found that the community’s sole heating, ventilation, and air-conditioning firm, Copper Highway Heating, did not have the bandwidth to add installation of residential heat pumps. After discussions between Rosenberg and the owner, the company agreed to provide installation services, and obtained the necessary training and certification.

The next challenge involved getting heat pumps to Cordova. Supply chain issues in 2022 delayed equipment arrivals by several months.

“The various installation, distribution, and design issues we ran into are representative of the types of challenges we will see in other parts of the country. It’s vital information to know going forward, and it could make future electrification efforts easier,” Rosenberg said.

In addition to Rosenberg, staff working on the project include researchers Chitra Nambiar and Alex Vlachokostas and project managers Abinesh Selvacanabady and Cheryn Metzger.