This week’s Energy Storage North America conference has a definitively upbeat theme. California’s 1.3-gigawatts-by-2020 mandate, Hawaii’s 200-megawattstorageRFP, and New York’s distributed energy incentives and utility pilot projects are all providing new markets for battery-based, grid-capable systems to provide services from millisecond-level grid balancing to multi-hour bulk storage.
With grid opportunity comes grid responsibility, however. Almost all of today’s big grid storage uses proprietary software and hardware to get the job done, with integration handled on a case-by-case basis. Standards for battery makers, inverter manufacturers, software developers, utilities and financing partners could yield big cost savings compared to the old way of doing things, as well as laying the groundwork for future innovations.
The MESA Standards Alliance, a group of Washington state energy storage players, wants to help solve that problem. On Wednesday, the alliance officially launched with a list of partners that includes storage software startup 1Energy, inverter maker Parker Hannifin, flow battery startup UniEnergy Technologies, big French grid player Alstom, and the Department of Energy’s Pacific Northwest National Laboratory.
MESA, which stands for Modular Energy Storage Architecture, also named four utilities as partners, including the three Washington state utilities that are deploying storage systems using the technology behind the standard, as well as California’s Sacramento Municipal Utility District.
Finally, as part of a collaboration with solar inverter standards group SunSpec Alliance that’s been going on since February, MESA released what it calls the “first open, non-proprietary energy storage system specification for public review.” It’s called the SunSpec Energy Storage Model Specification, or “MESA-Device,” and it lays out a standardized approach to integrating batteries, inverters, software control systems, and the interface that communicates all that data to the outside world.
“If energy storage is going to scale, then costs need to come down,” Rogers Weed, vice president of product management for 1Energy, said of the impetus behind standardizing these core interactions of a battery-based, grid-connected storage system. Battery costs continue to fall, driven by growth in manufacturing for the electric transportation market and the new call for larger, grid-connected systems, he noted. But the “soft costs” of integrating these systems haven’t seen the same economies of scale so far.
“I think the ability to lower the non-recurring engineering portion of a storage system’s cost by standardizing is definitely non-trivial,” in terms of the overall impact it can have on the total cost of grid-scale energy storage, he said.
Just how much cheaper, faster and simpler grid energy storage could get with these standards is hard to say, because nothing like this really exists yet. Of course, there are lots of players working on software to manage batteries behind the meter (Stem, GELI, Green Charge Networks, Coda Energy, SolarCity), as well as to manage them in relation to the grid (Greensmith, Younicos-Xtreme Power, A123-NEC, AES Energy Storage).
But 1Energy was founded in 2011 with the express goal of creating a standardized software approach to this challenge. Since then, it has been signing up the list of partners that now constitute MESA’s core membership, and it hopes that the benefits of this standards-based approach will be proven out in ways that get more utilities interested, Weed said. “How much different industry players pay attention to a standard like this will largely be a function of how much customers ask about it or demand it."
The new MESA-Device specification with SunSpec could go a long way toward introducing the benefits of this approach to a wider audience. Since February, the alliance has formed a workgroup including 1Energy and inverter makers including Advanced Energy, SMA, Outback Power, Ideal Power Converters, and Loggerware, to set up the new specification.
SunSpec has been working for years to standardize a whole host of new functions for the Modbus protocol used for most inverters, both to serve the owners of the solar systems and the utilities they’re connected to. It’s also playing a lead role in California’s smart inverter plans, which are aimed at setting up a whole list of required capabilities and communications features for future solar inverters.
“These platforms are built to last a long time,” TJ Keating, advisor to the SunSpec Alliance, said in a Wednesday interview. “If they’re not built on standards, well, how much software budget do you have in your O&M budget?” That’s the extra cost that SunSpec inverter partners have tried to avoid by going to a standardized approach.
Adding batteries to the systems in question adds a whole new layer of complexity, he said. “If you look at some community energy storage applications, it might cost $100,000 for a 25-kilowatt-hour system,” he noted. That’s the same amount of energy storage that now comes in a Nissan Leaf electric vehicle, which is now selling for less than $30,000 with incentives and rebates -- and with the Leaf, you also get a car to drive around in, he noted.
“I truly believe we can help with that $100,000 versus $30,000...problem,” he said. “I think a battery for a house should cost between $10,000 and $20,000, a done deal.” That’s a pretty aggressive cost target for on-site energy storage, though states with self-generation incentives like California can help bring small battery systems within that price range today.
The MESA alliance is also working on standards for a “master control” system that manages individual energy storage assets at grid scale, Weed said. That’s called the MESA Energy Storage System, or ESS, and it’s not yet ready for public release, though the group is working on it, he said.
GTM Research and the Energy Storage Association trade group have just formed a partnership to offer analysis of U.S. grid-scale storage markets, policy and technology. It’s hard to say how new standards like the one MESA and SunSpec have released, or the ESS system that MESA is working on, could affect those trends. But if the role of standards in information technology is to serve as a guide, it could be an important part of bringing energy storage from utility experiment to mass-market product.