Protecting energy storage from fire risk
As global leaders push to meet ambitious environmental targets, the energy storage market continues to grow rapidly around the world.
Globally, it’s calculated that around 387GW/1, 143GWh of energy storage capacity will be needed to support rising demand from 2022 to 2030. That exceeds Japan’s entire power generation capacity for 2020. China and the United States are still leading the way, with Europe set for a significant increase in capacity following the current energy crisis.
However, as more energy is stored, more batteries are being used to higher capacities, and this brings about significant fire risks – with many customer seeking stronger reassurance on fire safety as the market continues to expand.
Kristoffer Eldin, managing director at Dafo Energy Storage Protection, explores the different risks and the solutions needed to control these risks effectively, ensuring a safe global transition to a greener future.
A changing energy landscape
Extensive discussions at COP and other environmental conferences have ignited a growing volume of conversations around carbon emissions. This is seeing governments around the world continue to push ambitious sustainability agendas.
A key part of these agendas focuses on the global transition to a net zero future by 2050. To achieve this goal, it’s estimated that annual clean energy investment will need to more than triple globally, to around £4t, before 2030. Undoubtedly, this will place extreme pressure on energy storage around the world, and as a result, we’re already seeing an unprecedented increase in demand to boost energy storage capacity globally.
As more individuals and organisations switch to sustainable energy, global reliance on electricity is skyrocketing. The resulting ‘electrification’ of machinery, vehicles and other equipment powering domestic homes and everyday business operations is inevitably having a positive impact on global carbon emissions. However, it’s also driving an increase in the number of batteries (predominately lithium-ion (li-ion) batteries) needed to store and distribute the energy. That brings about its own fire safety risks, which are quickly becoming evident through recent battery fires at global energy storage systems.
Unpicking the risks…
The predominant risk presented by increasing energy storage capacity with li-ion batteries is thermal runaway.
Thermal runaway is an extremely dangerous state, which arises as a result of a malfunction in a battery’s cells. That malfunction can be caused by a number of factors, including physical damage to the battery, overcharging, overheating, overvoltage or mechanical failure, for example. When in thermal runaway, a battery will experience rapid temperature rises, which will quickly lead to it releasing additional energy, which will further increase temperatures to potentially dangerous levels.
If these rapid temperature spikes aren’t controlled quickly, the process of thermal runaway will progress, where the battery can be subject to fire (which can spread quickly across battery cells and to other nearby batteries), hazardous gas emissions and potentially also large explosions. The toxic emissions can include carbon monoxide, methane, as well as hydrogen fluoride, which – if it reacts with water or moisture in the air – can create an acid presence, increasing safety risks.
Where batteries are stored close to one another, as is increasingly the case in energy storage facilities as they expand to meet rising demand, it can cause much larger safety risks, as the risk of thermal runaway will spread from one battery to the next, amplifying the potential consequences.
A distinct lack of regulation
Disappointingly, there’s a clear lack of regulation governing the safety of energy storage facilities around the world. As the electrification movement is still in its relatively early stages, ‘how to best ensure safety’ is still largely debated by many insurers and government bodies, and the outcomes of these discussions hasn’t been shared widely across the market yet. In America, there are some advisory standards, such as UL 9540, however these aren’t yet mandatory and aren’t replicated around the world.
In the absence of legal standards enforcing best practice safety controls, all too often it’s falling down to price, with facilities asking for the cheapest solution. The short-term result of this is installing a lower-quality detection system which isn’t fit for purpose – or even avoiding installing a system altogether. In the longer-term, however, there’s a clear trade off in cost – as the cost of the risk, once realised, will often far outweigh any cost associated with selecting the right system from the outset.
Without mandatory safety guidelines, leaving critical safety decisions down to price at the hands of organisations is incredibly dangerous.
Out with the old, in with the new… or not?
It’s not just new batteries causing risk. With more electricity being used in almost every application, there’s a growing presence of older, scrap batteries in everyday waste streams. These need to be stored carefully, as they’re subject to the same risks, on an arguably larger scale due to the harsh environment of waste processing streams.
There’s also an increasing presence of scrap batteries in manufacturing processes. For example, if car manufacturers face issues with batteries in vehicle development, these will often be replaced in the final model (after the faulty batteries have been manufactured on a large scale). In these situations, the faulty batteries are often discarded, and will need to be stored safely before being repurposed for use in alternative models or parts. Again, the same fire risks apply, which need to be addressed in these facilities’ fire suppression solution.
Overcoming risks to enable a safe, green future
An important point to note is that traditional fire safety solutions will often not effectively eliminate risk for li-ion batteries. This is because, in thermal runaway, a battery is able to produce its own source of oxygen to sustain a fire from within, making suppression using traditional means particularly challenging. There are new solutions being trialled, including aerosols and powders, however, while these can extinguish initial flames, they’re often unable to halt thermal runaway entirely or eliminate its safety consequences.
Research demonstrates that, to extinguish these kinds of fires effectively, suppression solutions need to apply enormous quantities of water for extended periods of time – and that’s just for an individual battery. For a whole unit of batteries in an energy storage facility, the amount of water needed would be astronomical, which directly contrasts the environmental initiatives that led to the need for the sustainable energy in the first instance.
As a result, there’s a need for a new, unique protection system. Following extensive research and testing into li-ion battery fires, Research Institutes of Sweden and Dafo Vehicle Fire Protection discovered that an early fire warning system, aided by spot cooling, ahead of thermal runaway is often the most effective way to prevent thermal runaway from progressing. The key is to detect potential battery failure before temperatures begin to rise, as the battery vents low levels of carbon monoxide.
With a system built inside the energy rack, temperatures can be cooled from the inside of the battery pack immediately, containing risk and mitigating the consequences for the energy storage facility.
A risk destined to grow
Inevitably, as demand for sustainable energy continues to rise, the risks are only going to grow. Increasing sustainability is essential, but doing so safely is critical.
To find out more, visit Dafo’s Energy Storage Protection.
Written by Kristoffer Eldin, Managing Director at Dafo Energy Storage Protection