Grid-level storage continues to grow as one of the pillars of energy management, as utilities invest in distributed storage systems as alternatives to peak power plants. Storage systems are capable of providing peak demand response, frequency regulation, and power factor correction. But with so many types of batteries on the market, each with its own pros and cons, it’s difficult for designers to determine which battery technology meets the needs of a given application. Greensmith Energy recently enhanced its GEMS4 energy storage platform to help engineers choose the best system for the job, and to monitor the system once it’s in place.
The GEMS software platform manages the complete life cycle of energy storage systems. The technology-agnostic software integrates all storage system components, including batteries and inverters, manages storage assets to optimize battery performance, and provides connectivity with utility SCADA systems. GEMS allows operators to manage frequency regulation, ramp rate control, and integrate renewable energy sources. In its fourth generation of development over six years, GEMS uses advanced, proprietary algorithms to maximize “battery-dollars.”
GEMS4 adds two new applications to the software suite: StorageModelTM, a simulator, and StorageViewTM, a monitoring and control system. I recently interviewed Leesa Lee, Senior Vice President of Management and Marketing at Greensmith, who answered my questions about StorageModel and then gave me a live demonstration of the StorageView software.
StorageModel
Design engineers can use StorageModel to simulate various battery technologies and configurations to see how they’ll perform under given conditions. Some batteries handle multiple deep discharge cycles very well, while others degrade quickly when their depth of discharge is exercised too much. Some have a preferred “rest period” between cycles. Each battery has its own unique degradation curve that shows how it will perform as it ages. StorageModel takes these factors into consideration, allows the designers to define working conditions, and see how each battery will perform over the life of the system. This helps engineers to make informed decisions about which battery to use.
StorageModel uses specifications taken directly from manufacturers’ data sheets, as well as empirical data from previous systems that Greensmith has installed. At the moment that information is somewhat limited, simply because it’s such a young industry. As more data becomes available, the simulation algorithms are refined.
The StorageModel application is currently in beta testing with Greensmith’s partners and developers. It’s also available for limited users who are bidding on upcoming projects. The company expects to release it to the general public later in 2015.
StorageView
Once a system is in place, StorageView allows operators to monitor, control, and troubleshoot the system remotely or on site. StorageView shows battery charge levels, temperatures, HVAC status, safety systems, and more. Here’s a screen capture of the live demo. This is monitoring an actual 20 MW system that Greensmith recently installed. The red triangle indicates an alert; at the time of the demo the system was down for maintenance, so a lot of red triangles appeared.
Below we see a color-coded 3D view of the system. The block in purple shows a cell malfunction.
The 3D view, with its abundance of analytics, helps operators triangulate on the cause of a fault, making diagnostics more efficient and less costly. Lee gave me an example of one system where a unit appeared to malfunction, but within minutes the technicians determined that it was a sensor problem. Without the multiple metrics, it would have taken much longer to troubleshoot.
GEMS4 is a battery-agnostic system. According to Ms. Lee, most of Greensmith’s customers use Li-ion batteries, due to their combination of energy density, safety, and flexibility. But they also work with systems that use lead-acid batteries and flow batteries when those make the most sense.
Staying On-Grid
I asked Lee if Greensmith intends to expand its operations towards the residential energy storage market. She said that they have no immediate plans to go behind the meter - they’re staying with grid-level storage, the company’s core strength. As that’s a burgeoning industry, I’m guessing they’ll have plenty of business opportunities.
Budding engineers and programmers take note: energy storage looks like a serious growth field. It’s a good time to get on board.
Images courtesy of Greensmith