Lightning strikes led to a major blackout in the UK power grid, and battery energy storage systems show their talents at critical moments
On August 9th, the United Kingdom lost 1.5GW of power generation capacity due to lightning strikes on the power transmission system, causing a blackout affecting more than 1 million households, which only returned to normal after 50 minutes. The latest report pointed out that if there is no energy storage battery system rescue, the impact may be longer. Heavy thunderstorms caused disasters and lightning strikes in the transmission and distribution lines of the UK. In addition to reducing the grid frequency (power frequency), there were also rare power outages. The Rhein Group (RWE) Little Barford Natural Gas Power Plant with a capacity of 660MW suddenly ceased operation at 4:52 pm. 45 seconds later, Hornsea One, the world's largest offshore wind farm, also failed, and 1.5GW of electricity was lost within 1 minute. The grid The frequency is lower than the safe operation frequency.
The grid frequency is an indicator of the balance of supply and demand, indicating the frequency of AC power on the grid. In the UK, this kind of oscillation occurs 50 times per second, so the grid usually uses 50 Hz. The frequency in the UK had dropped to 48.9 Hz at that time. The lower the frequency, the more difficult it is for traditional power plants to feed electricity into the grid.
Tim Gree, director of the Energy Futures Laboratory at Imperial College London, said that this is because the performance of large generator sets will decline as the frequency decreases, which is also a potential out-of-control device. The British National Electricity Supply Company (National Grid) interrupted the electricity supply of 5% of households to ensure the normal use of electricity for the remaining 95%.
However, the battery energy storage system is not limited by frequency, as long as the equipment is turned on and the power is transmitted at 50Hz power frequency to turn the tide. The National Power Supply Company of the United Kingdom said that during the power outage, the battery energy storage system with a total capacity of 475 MW has made a lot of progress.
The largest output is the photovoltaic power plant near London Luton Airport, equipped with a total of 6MW lithium battery energy storage system. The person in charge of the energy company Upside Energy said that batteries provide power to the grid at sub-second speeds. Although 6MW sounds good, the capacity is similar to that of a medium-sized wind turbine. If the average household consumes an average of 2000W, 6MW can meet the needs of 3000 households.
In addition, the battery of British renewable energy developer RES provided 80MW of electricity at a critical moment. RES stated that the grid frequency was dropping at a rate of 0.144 Hz per second, but the battery started charging within 25 seconds and switched from the charging mode to the discharging mode, helping to restore the frequency.
Finally, with the assistance of many parties, the grid frequency exceeded 50Hz at 4:57 pm. The National Power Supply Company pointed out that it took 3 minutes and 47 seconds for the battery energy storage system to restore the grid frequency to normal, far more than 11 minutes ten years ago. Even faster. This incident is similar to the 2017 Tesla battery in South Australia. At that time, at the moment the thermal power plant tripped, the Tesla battery delivered 100MW of electricity to the grid in a very fast 140 milliseconds, showing that the energy storage system is of great benefit to the stability of the grid.
