Where do most major energy storage fires occur?

• ‍63 major energy storage failure events occurred globally during the period 2011-2023
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• ‍US database reveals which countries had the most storage failure events
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• Manufacturers of battery modules associated with the incidents also named

South Korea and the US are the countries that have suffered the largest number of utility scale or industrial energy storage-related fires, data from a US-based electricity sector research organisation shows.

A database maintained by the California-headquartered Electric Power Research Institute (EPRI) reveals that, from 21 September 2011 to 27 July 2023, there were a total of 63 “utility and commercial & industrial-scale energy storage failure events”. Just under half of the events (31 in total) were located in South Korea, the data shows, meaning the East Asian country has experienced the most major incidents during the 12-year period.

Meanwhile, the US was the country that experienced the second largest number of utility and commercial & industrial energy storage failure events, with a total of 19 during the period. Elsewhere, there were three such events in Australia, and two each in China, Taiwan and France. The countries where one event was recorded during the 12-year timeframe were Germany, the UK, Belgium and Japan.

Number of failure events fluctuates from year to year

With regard to the times during the period the failure events took place, it is difficult to draw conclusions as to whether there is a trend for an increasing, or decreasing, number of incidents each year. The database shows that, between 2011 and 2017, there were never more than two failure events per year (with either one or none in five of the years in that period). However, in 2018, the number of major storage failure events rocketed to 16, before dropping down to eight in 2019, and falling again to just four in 2020. However, incidents increased to 10 in 2021, before climbing again to 12 in 2022. The database records a total of six such events in 2023 so far.

It is important to place the country figures in context and make note of the relevant caveats. The respective totals for each nation are obviously relative – for example, South Korea has experienced over 50 per cent more commercial & industrial energy storage failure events than the US during the period, but has only deployed a fraction of the amount of energy storage that has been installed in the US market. It should also be taken in to account that reporting standards for energy storage fires may differ from country to country. However, in a sector in which statistics on fire events is scarce, the EPRI data provides a useful insight into the scale of the problem.   

The EPRI website also provides details of the “module type” involved in relation to the failure events. Module types are not detailed for every event, but the modules that do appear in the list are referred to as follows:

Module type (number of times cited in EPRI database)

LG Energy Solution  (6)

LFP (4)

Powin Energy (3)

Tesla (3)

LG Chem  (2)

Gotion High-Tech  (1)

Lead Acid  (1)

Ruipu  (1)

Samsung SDI  (1)

SimpliPhi Power LFP  (1)

SK Innovation  (1)

Public opposition to energy storage could grow significantly

A report published last week by Firetrace International, a supplier of fire suppression technology to the renewable energy industry, warned that there was a real danger that public opposition to energy storage could grow significantly as a result of fire risk fears, threatening critical battery deployment and, as a result, net zero goals. The report said that concern for energy storage fire risk is rising, and incidents that do occur tend to attract a significant amount of negative publicity. As a result, projects in the US and Canada are being postponed and politicians in the UK are calling for battery storage systems to be subject to checks by fire services.

The Firetrace report also stated that high-profile fire incidents in battery storage had impacted on the insurance market, with the result that appetite to cover energy storage projects has declined, with some insurers even exiting the market. This had resulted in increased premiums, higher excesses, and difficulties in securing 100 per cent cover.

The report also stated that regulation had a major role to play in mitigating battery storage fire risk but, at present in the US, fire regulations vary from state to state, resulting in an array of different regulations informing design and installation. It added that, while manufacturers in some states consult fire suppression specialists, others do not. The report suggested that US states should adopt the International Fire Code (IFC) in place in New York and California.

Greater focus on storage fire risk

Earlier this year, the US-based International Association of Fire Chiefs said that, as the use of lithium-ion batteries continues to grow, so does the potential risk for first responders who are “called upon to mitigate associated fire incidents and hazards”. Subsequently, the association ran a campaign, which focussed on five key areas: recognition of hazards; firefighting operations; firefighter safety; post-incident considerations; and public education.

In October 2022, the American Public Power Association (APPA) highlighted how a fire at Pacific Gas & Electric’s (PG&E) Moss Landing battery storage facility in California had brought “fresh attention to safety issues tied to energy storage”. Following the fire, one newspaper used its editorial column to state that the fire was a “reminder that battery blazes are becoming increasingly common and destructive – and safety measures, including fire drills, for residents around storage facilities will have to be put in place and widely disseminated.” The article also raised concerns that “lithium-ion batteries might be releasing toxins into the air”. The Moss Landing fire also led the APPA to highlight comments made three years earlier by a commissioner from the Arizona Corporation Commission, who said that the lithium-ion chemistries used in battery storage facilities “create unacceptable risks”.

Elsewhere, as highlighted in the Firetrace report, battery storage projects in the US and Canada have had to be postponed as a result of fire risk concerns raised by local communities. In April this year, residents in Maryland’s Prince George’s County opposed plans for a lithium-ion battery storage system citing fire and explosion risks. Meanwhile, in the New York borough of Staten Island, plans for 120MWh of battery storage were withdrawn due to the local community’s fears about fire risk and potential exposure to toxic chemicals.

In the UK, politicians have sought to highlight the risks associated with battery storage systems and called for them to be subject to checks by fire services. One UK Member of Parliament has called for energy storage installations to be classed as ‘hazardous’, which would mean the UK Environment Agency, Health and Safety Executive, as well as fire services would be statutory consultees when planning applications are considered.

Cell imbalance common precursor to battery fires

In an effort to minimise the risk of battery storage fires, energy companies are investing in technology providers that have developed data analytics tools that can detect, at an early stage, battery defects or malfunctions that can lead to major safety issues, including potential fire risk. For example, EDF was one of the early investors in Paris-headquartered battery analytics systems developer PowerUp, which claims that, contrary to popular belief, lithium-ion batteries' fires are most commonly a result of cell imbalance issues.

PowerUp says that one issue that heightens fire risk is that it is only the more sophisticated battery management systems that include a microcontroller that can evaluate battery SoH [state of health] and SoC [state of charge]. PowerUp argues that accurate monitoring of SoH and SoC is vital in order to address the issue of cell imbalance. “Unfortunately, BMS [battery management system] components failures can happen, and SoH and SoC measurement accuracy is often limited,” a PowerUp report concluded. “Among battery faults root causes, BMS failure leads to battery unsafe overuse conditions (over-temperature, over-voltage or high over-charge).” With fire risk concerns leading to the cancellation of energy storage projects, the race is on among project developers to minimize the danger of battery fires and quell fears among local communities about battery systems being built in their neighbourhoods.

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