Dresden 12 MWh
Battery Energy Storage System (BESS)
In fall 2022, Upside Group installed a 12 MW battery storage system at the Dresden Süd site in Saxony and put it into operation in December 2022. Once again, Upside relied on the renowned manufacturers Narada, SMA and Siemens, who had proven themselves in previous projects. However, for the first time, lithium iron phosphate batteries (LiFePO₄) were used instead of lead-carbon dry-cell batteries. This decision was based on years of prior due diligence. In addition to various inspections of cell production in China, real operating data of a battery storage system active in the primary control reserve (PCR) was evaluated over a period of 5 years and these operative requirements were compared with the specifications of the LiFePO₄ battery cell.
Location
The Dresden Süd substation of the grid operator SachsenNetze is an important hub in the regional power grid. It connects the high-voltage grid with the medium-voltage grid and plays a key role in supplying the Dresden region. Its function in the context of grid expansion for the integration of renewable energies and security of supply in the Dresden region is particularly noteworthy, especially with regard to the industrial development of technology companies such as Infineon in the north of Dresden.
The substation is part of a larger strategy by 50Hertz and SachsenNetze, which are driving forward the expansion and reinforcement of the extra-high voltage grid in the region. This also includes the planned connection to a new 380 kV line, which is necessary for a future-proof energy supply.
The battery storage system is located in the immediate vicinity of the Dresden Süd substation.
Performance
In addition to the frequency-controlled power provision in the PCR market, the Dresden Süd battery storage facility also provides automatic frequency restauration reserve (aFRR). aFRR is used to stabilize the grid frequency following an imbalance between electricity generation and consumption. It follows the primary control reserve (PCR) and serves to return the grid frequency to the setpoint value of 50 Hz in Europe. The response time plays a key role here. After all, it must be ensured that the requested power is supplied within the specified time. Upside ensures this by means of above-average system availability, operational readiness at all times, precise measurements and rapid communication with the grid operator.
Due to the extremely high grid utilization in the region, Upside has already configured and installed the Dresden Süd battery storage system in such a way that it can be black-started at any time. The system would thus be able to restart a power grid after a complete grid failure (blackout) without an external power supply.
Technology
Like all previously installed battery storage systems, the Dresden Süd energy storage system relies on proven technologies from renowned manufacturers. The power electronics and inverters come from Siemens and SMA, one of the world’s three largest manufacturers of battery inverters. However, for the battery cells used from the manufacturer Narada Power Source, Upside in Dresden opted for the Narada LiFePO₄ battery cell for the first time. The reason for this was that, compared to other lithium-ion batteries (e.g. lithium cobalt oxide), it is thermally stable and less susceptible to overheating or fire, while also having a long service life and high cycle stability. In terms of recyclability, the LiFePO₄ cell cannot compete with the lead-carbon cell used to date, but iron and phosphate are less harmful to the environment and easier to recycle than other lithium battery materials such as cobalt or nickel.
The decision was also positively influenced by the fact that the CO2 balance during transportation and installation of LiFePO₄ cells is more positive than with lead-carbon dry accumulators used to date. Last but not least, only around a third of the surface area is sealed for the same installed capacity, meaning that LiFePO₄ is also ideal for stationary energy storage and is now being used in parallel with the proven lead-carbon technology at Upside due to its safety, long service life and environmental friendliness.