pv magazine: Greensmith recently announced dramatic growth in the grid-scale energy storage market, with 23 MW worth of projects commissioned this year that are using its GEMS energy storage software platform. What are some of the factors behind that growth?
John Jung: The growth that Greensmith has seen has been dramatic. More importantly, what we’re seeing is the migration from small pilot systems to large systems that are being deployed under ROI [return on investment] expectations. While it is early to speculate, we are optimistic that we will continue to see significant growth in the number of projects in 2015. There seems to be little doubt that the market is embracing grid-scale storage.
pv magazine: You attribute the growth to utilities, renewable energy project developers and other customers who are increasingly using energy storage for a variety of applications. Which high-profile solar PV installations are using GEMS? And which utilities and other customers are also employing the software?
Jung: Customers that are using the GEMS software platform in conjunction with large solar PV installations include a commercial-scale solar developer and two California utilities.
pv magazine: How many customers and projects do you have in total and who are your core clients?
Jung: To date, we have delivered over 35 systems to 19 customers, including nine utilities. Our core customers are utilities and independent power producers (IPPs) that are looking to deploy and manage a fleet of grid-scale storage systems and developers who need a platform to integrate and operate multiple battery/PCS combinations.
pv magazine: How would you describe the current energy storage software market and the state of competition in the segment? Who are your major competitors?
Jung: The storage market is growing rapidly due to several significant drivers. These include the need to address the challenges associated with the penetration of renewables (the infamous Duck Curve); procurement mandates such as AB 2514, capacity requirements, technology validation, and the rising cost of electricity.
As far as competition, we are unique in the industry in that we offer both a technology platform as well as integration services to deliver turn-key systems. More broadly, there are software-only storage technology vendors such as GELI and 1Energy, and developers and integrators such as AES.
Our competitive advantage is that not only do we have a mature and robust software platform, but we also excel in development and integration. We believe that developing, installing and operating storage assets effectively requires deep understanding of all layers of the technology stack, from hardware to system topology to the application layer. We have spent six years perfecting our software platform, which is currently in its fourth generation. And having deployed 35 systems, we understand component interdependencies and can optimize full system performance and ROI.
pv magazine: One of Greensmith’s biggest advantages is the fact that the GEMS software is hardware agnostic. Is the number of different batteries and inverter/power control systems integrated with GEMS limited to 10 batteries and six inverter/power control systems? Are you constantly expanding the number of battery and power control systems that can be integrated with GEMS?
Jung: The GEMS platform has hardware agnosticism as a fundamental design principle. To date, there are 10 batteries and six inverter/power control systems that have been integrated with GEMS, but we are continuing to integrate additional components and will have another two batteries integrated before year-end.
pv magazine: What types of batteries are among the 10 currently integrated with GEMS?
Jung: Battery types currently supported by GEMS include lithium-ion batteries (from multiple vendors), aqueous sodium-ion chemistry batteries (from Aquion), and zinc redox flow batteries (from ViZn).
pv magazine: What role does software play in advanced battery technology?
Jung: We believe that you cannot deliver an advanced battery system without a strong software control layer. The GEMS software platform integrates every piece of hardware in an energy storage system, including batteries and inverters. It then manages this hardware to optimize the storage system for application performance, longevity, and return on investment.
The GEMS software platform also increases flexibility in the design, deployment and use of grid-scale energy storage systems. And because the GEMS software platform is hardware agnostic, it enables users to mix and match multiple types and brands of batteries and other types of hardware in the same system, thereby lowering costs, avoiding vendor lock-in and improving the systems overall return on investment.
In addition, energy storage systems running the GEMS software platform can be used for multiple applications. For example, because GEMS monitors and controls every piece of hardware and software in a storage system individually, the system could be used for demand response during one part of the day and then later used for grid balancing or Electric Vehicle (EV) charging later in the day.
pv magazine: What are the advantages of focusing on a software-oriented and battery agnostic approach rather than on developing the best battery possible?
Jung: There is no such thing as "the best battery possible" because batteries are very nuanced and different batteries excel in different use case and applications. For instance, some batteries are better for energy-centric use cases while others excel in short-duration, power-centric applications.
There are many companies focusing on battery technology improvements. We are focused on developing better software to manage those batteries and integrate them into complete energy storage systems. We complement each other better batteries and better software both result in better energy storage systems.
pv magazine: What kinds of applications does the GEMS software platform support?
Jung: Energy storage systems that utilize the GEMS software platform can be used for a variety of applications, including frequency regulation, capacity, ramp rate control, Transmission and Distribution (T&D) deferral, and renewables smoothing.
pv magazine: How important is the solar PV market for Greensmith and what share of the company’s overall business is attributable to solar PV projects?
Jung: The solar PV market is an important market for Greensmith, but it would be difficult for us to attribute a specific percentage of our business to solar PV projects. This is because many times PV is only one of many factors that is driving the use of energy storage for applications like frequency regulation, capacity and ramp rate control.
pv magazine: In what international markets are you active outside of the United States?
Jung: We are currently deployed in Australia and are evaluating additional countries for expansion.
pv magazine: What advantages does the flexibility of Greensmith’s energy storage systems offer in terms of mobility and re-purposing?
Jung: Because storage is by nature flexible and the Greensmith system is software-based, we have strong support for mobility and re-purposing. In one example, a pilot storage system was deployed by a research institute in a lab location for testing purposes. Once the tests were concluded, the system was physically moved to an office parking structure and the Greensmith software was updated to support Level I and Level II EV charging.
Greensmith has offices in Rockville, Maryland; Reston, Virginia; and Emeryville, California.