Ask the expert: How to choose the right inverter, install strategically and save on energy costs
At the ees Forum during ees Europe 2024 in Munich, experts from Fenecon, Intilion AG, Pylon Technologies, RCT Power, Socomec and Stabl Energy gave exciting insights into business strategies for commercial storage systems.
Solar storage systems have become a standard part of domestic photovoltaic installations. The technical developments in this market segment also benefit systems that help commercial businesses and industrial companies reduce their energy costs.
A presentation by Kamel Silmy, CTO Germany of Pylon Technologies at the “Reducing Energy Costs with Commercial Storage” session, showed how much the coverage of different market segments varies. The session took place at the ees Forum during ees Europe on June 20. “The installed storage capacity for smaller solar installations with a capacity of up to 30 kW is more than 21 percent of the total installed photovoltaics capacity in Germany. The installed storage capacity of utility-scale installations above 1 GW is 5.46 percent, that of commercial applications between 30 kW and 1 MW only 0.89 percent. That means there’s huge market potential in this segment.”
Louis Fuchs, Sales Manager at Intilion, gave some practical insights into the installation of commercial electricity storage systems. “Anyone considering purchasing a solar storage system for their business need to decide what they want to use it for. A storage system can be used to reduce peak loads (for peak shaving), to optimize their self-consumption, to save the electricity they have produced, or to create their own stand-alone power system in order to secure electricity supply in the event of a power grid failure,” says Fuchs.
To decide on the purpose of use, you need to consider current and future consumption data as well as generation data and grid connection data. “The full load hours, in other words the ratio between electricity purchased from the grid (in kWh) at peak load per year plays a key role for the decision: A system with self-consumption optimization is financially viable if the annual full load hours are below 2,500, while peak shaving becomes profitable from 2,500 annual full load hours onwards,” explains Fuchs.
Jan Thäter, Project Planner at Fenecon, is an expert on cost optimization in variable electricity tariffs. In his presentation, he explained that conventional solar storage systems switch to discharge mode after sunset, thus discharging the storage system at a time when the price for electricity is low. Fenecon uses artificial intelligence to offset the electricity demand forecast of companies against the forecast of the electricity spot price. “That means that the electricity storage system’s battery is charged at night, at a time when the electricity tariff is lower, and discharged during the day, when the electricity price rises. If any more solar power is produced, it is given priority,” explained Thäter. So, the goal is to provide both cheap off-peak electricity and the solar power produced during periods when electricity prices are rising.
Eric Rüland, Managing Director at RCT Power, reported on a recent study by the University of Applied Sciences for Engineering and Economics HTW Berlin. He stressed that in smaller electricity storage systems, the efficiency in the partial load range is key because at 100 to 300 watts, private and commercial consumption is often low during the night. With an electricity consumption of 100 watts, RCT’s 10-kW hybrid inverter demonstrated a discharge efficiency of 86 percent in the test performed as part of the HWT study, while the lowest-performing system only achieved 54 percent.
Even with an electricity consumption of 500 watts, the difference between RCT Power and the worst-performing inverter was still 10 percentage points. He concluded that consumers with a low electricity demand at night should choose an inverter with a high partial load efficiency to optimize the use of their battery storage.
In addition to increasing efficiency, a key factor determining the economic viability of electricity storage systems is their service life. STABL Energy equips storage modules with a proprietary actuator and integrates them dynamically, which does away with the need for a central inverter. According to Dr. Nam Truong, CEO of STABL Energy, this approach can help cut energy losses by up to 70 percent, reducing overhead and carbon emissions by up to 40 percent per year.
Ruben Glowczak, Sales Engineer for Energy Storage Solutions at Socomec, a French manufacturer, promised savings in the set-up and installation of containerized stationary electricity storage systems.
Socomec offers pre-assembled and pre-wired storage systems that require less installation time and can be delivered as standard components. The prefabricated modules are mounted on a base plate (so-called skid) and are easy to transport and install.
As demonstrated by the optimizations across the entire supply chain presented at the ees Forum – from planning storage systems to installing and operating them –, the electricity storage industry showed plenty of potential for innovation. We can expect to see more savings in the energy supply of commercial businesses and industrial companies in the future.
Every year, ees Europe, the continent’s largest and most international exhibition for batteries and energy storage systems, provides a networking opportunity for the industry’s key players – all under the motto “Innovating Energy Storage”. It focuses on the latest technologies, trends and market developments. ees Europe will take place from May 7–9, 2025 as part of The smarter E Europe at Messe München.
