BONNEVILLE POWER ADMINISTRATION
Water heater innovation could boost NW renewable energy development

You might not think much about the large water heater sitting in your garage or basement, as long as you get plenty of hot water when you turn on the faucet. But a newly completed BPA Technology Innovation study shows that your electric water heater could provide essential storage for renewable wind and solar power. This research also created a path to making this technology widely available to Northwest residents.

Co-led by the Bonneville Power Administration and Portland General Electric, the study shows that if just 26 percent of Oregon and Washington's electric water heaters were controlled by utilities - a type of technology called demand response - the Northwest could create an extra 300 megawatts of storage capacity. To help understand how much power that is, just one megawatt is enough to power 700 to 800 average sized Northwest homes.

BPA and PGE published the study Nov. 28 and are calling it the largest smart water heater pilot program ever completed. The three year study included 277 participants whose water heaters were equipped with an open standard communication port called a CTA-2045, similar to a USB port. Eight Northwest utilities in the Eugene, Portland, Tri-Cities and Seattle markets participated in the pilot using local FM radio waves to communicate with the water heaters.

Developed in coordination with the Electric Power Research Institute, the CTA-2045 allows utilities and other service providers to send commands to appliances by plugging a communication device into the port. The study showed that the technology could be used to turn on water heaters when wind and solar energy is the most plentiful and the cheapest. That leaves the end user with hot water to use later, when there may not be any wind or solar power available. A smart control feature at the water heater prevents the customer from running out of hot water.

While earlier studies have tested the ability to adjust water heaters a few times a year to reduce power use during times of high demand, this study showed that water heaters can also be adjusted hundreds of times a year to match the variability of renewable generation.

"We're really happy with the results from the pilot," says Tony Koch, a BPA Energy Efficiency mechanical engineer.  "What's great is that this communication technology could also work on space heating and cooling systems, dishwashers, electric vehicle chargers, TVs, refrigerators, and almost any household appliance that consumes significant energy."

While some U.S. utilities are using proprietary cloud-based applications and a Wi-Fi connection to manage the energy use of appliances in homes, the CTA-2045 technology opens the door to innovation. Any manufacturer or entrepreneur can develop devices that are compatible with it. And it still allows for connections to the cloud.

Now that this technology has been tested, BPA and PGE want to work with water heater manufacturers to build CTA-2045 ports into all new water heaters, making it easy for consumers to participate in demand response.

"The near-term goal is to have manufacturers include CTA-2045 in most water heaters shipped to the Pacific Northwest," says Conrad Eustis, director of Retail Technology at PGE. "Our long-term goal is to create a simple customer experience that can be replicated with any major appliance. The CTA-2045 technology greatly reduces utility cost to implement demand response while at the same time reducing lifestyle impacts to the customer."

While it may take as long as 20 years to get there, the end result could be water heaters storing hundreds of megawatts of energy, supporting ever-increasing amounts of renewable power on the grid.