The Wattsmart Battery DR Program

Partnership with rooftop solar customers is helping Rocky Mountain Power to accelerate its transition to the renewable grid of the future

The current electric grid was designed to facilitate the one-way transfer of energy from large power plants, such as coal, hydro, and nuclear to end-customers. However, with the transition to renewable energy, the electric grid needs to evolve and innovate to manage the continued growth of on-site customer energy, such as solar. The relationship between utilities and customers is therefore evolving into a two-way connection. Today when large amounts of utility customers install rooftop solar it creates grid instability. To solve these issues, Rocky Mountain Power (RMP) partnered with its rooftop solar customers to develop and launch the Wattsmart Battery DR Program with the goal of accelerating the transition to the renewable grid of the future.  

Impacts of Rocky Mountain Power's Wattsmart Program 

• A first-of-its-kind solution for customers who use batteries to turn intermittent solar into a manageable smart grid asset capable of providing advanced DR functionality.
  
  
• A repeatable battery DR Program that can scale-up and work anywhere in the country with various battery manufacturers.
  
  
• Development of new utility engineering standards and the removal of industry barriers that have enabled rooftop solar and utility industry collaboration.

The Wattsmart Battery Program innovation journey started in 2017 as a partnership between the utility (RMP), a local developer/RMP customer (The Wasatch Group), and a battery manufacturer (Sonnen) to innovate through policy and technical constraints and develop a solution for local utility control of over 600 batteries powered by solar at a 600-unit apartment complex called Soleil Lofts.

The Soleil Lofts project won Utility Dive's "2019 Project of the Year" and served as a pilot that evolved into the Wattsmart Battery Program. This program was then offered to all RMP Utah customers in 2020, and is now expanding into Idaho and other states. The pilot program forms the backbone of the scalable Wattsmart Battery Program and includes:

• Development of a Battery Grid Management System (BGMS) in partnership with Sonnen that allows RMP to connect with and dispatch customer-owned batteries to keep the power grid stable and avoid power outages.
  
  
• A BGMS that's connected to the Western energy grid and automatically reacts in real-time (within 50 seconds), based on system needs. 
  
  
• A Virtual Power Plant resource in partnership with Sonnen that allows thousands of small batteries to be controlled as a group, transforming distributed residential solar power into the equivalent of one large power plant resource.

• Automatic use of batteries when the overall grid is at risk of blackouts due to voltage issues resulting from the intermittency of renewable energy. 
  
  
• The ability to schedule real-time charging of batteries from excess solar during the day so as to provide energy in the early evening when power needs are highest.
  
  
• Automatic backup power for individual customers if there is a grid power outage.
  
  
• Innovative partnership with solar installers to work together for a sustainable energy grid by promoting and incentivizing a new residential standard of solar + battery. 
  
  
• Thousands of customer batteries participating in the program, and growing.
  
  
• Exponential growth with a projection of over 3,000 new participants in 2023. Growth expectations of 100 MWs within five years.
  
  
• Every day over the past year the Wattsmart batteries have been charged by on-site solar and then dispatched in the evenings to power customers with stored solar, when power is needed the most.
  
  
• Evolved utility relationship with solar installers to a partnership that focuses on sustainable business solutions for the renewable grid of the future. For example, the largest solar installer in Utah partnered with RMP to transition their business model to include qualified Wattsmart batteries on 100% of all their thousands of installations.
  
  
• Transformed the Utah market by incentivizing customers with existing rooftop solar to install batteries.
  
  
• Featured in articles published by Forbes, New York Times, Bloomberg, and T&D World.
  
  
• Established performance design standards for battery manufacturers to ensure batteries can be used by utilities to keep the grid stable. This critical component ensures future batteries will work harmoniously and out-of-the-box with the power grid.