Hawaiian Electric Adds 2.5 MW Of Demand Response Capabilities With Very Unusual “Batteries”

Hawaiian Electric (HECO) recently added 2.5MW of grid services to its grid, allowing it to store energy during peak solar and wind production periods, and did so without any traditional batteries, flywheels, or pumped hydro.

Even better, the hardware required is very minimal, and in fact, most of it already exists in every residential grid in the world.

Hawaii, like many islands, is largely powered by diesel generators, the cost of electricity is insanely high, making Hawaii a great laboratory for cleantech startups.

One of these startups, Shifted Energy, a developer of software and controllers that retrofit electric water heaters, has partnered with Open Access Technology International (OATI) to outfit up to 2,400 water heaters with smart controls through Hawaiian Electric’s Grid Services Purchase Agreement.

Shifted Energy installs controllers on residential water heaters to allow utilities to effectively use them as batteries.

The company will deploy a 2.5 megawatt storage system for HECO, the company announced last week, creating what’s often referred to as a virtual power plant, or VPP.

The controllers are free to participants and they will receive a monthly bill credit between $3 and $5, depending on how often their heater has the ability to contribute to the program.

The company has spent years optimizing an algorithm that takes into account typical hot water usage, so as to maximize the positive outcome and still supply hot water when needed. Here in Hawaii, peak demand time (about 5–9 PM on weekdays) is a time when the grid is strained, and when the most dirty energy is being used.

So, by shifting the time a water heater kicks on and warms up to times when there is excess solar on the grid, the technology can help reduce the peak demand, and therefore, the amount of dirty, expensive energy that is used during that time.


Reference- Clean Technica, Shifted Energy website & PR,