EVSE’s Post

Transcript

It's a well established fact that electric vehicles both lower incidence of fires compared to their internal combustion counterparts. So why then do reports of electric vehicle fires and charging incidents seem to dominate the news cycle? The answer lies in the nuances of these fires and the height and risk they pose when they do occur high. I'm IRA from MVC Head of Engineering and today I'm joined by Alistair Curtain, an associate fire safety engineer from ADP Consulting. We're diving into a topic. Today, that's been sparking headlines and raising eyebrows. EV charging and fires. As providers of EV charging solutions, we understand the importance of addressing concerns surrounding EV fires head on. An EV is any vehicle that has a lithium ion battery and can be charged via connection to a power supply. So this includes both battery electric vehicles and hybrid electric vehicles. Someone run away. Something you may have heard reports of Evie fires. An EV has a lithium ion battery pack, which generally consists of hundreds of individual battery cells. A single lithium ion battery cell can undergo what is called an exothermic reaction via mechanism such as mechanical damage, overcharging, and internal short circuits which increases the heat through the battery cells. This reaction can increase the temperature of adjacent cells and can cause a chain reaction to occur known as thermal runaway. The heat generated can cause the batteries to ignite. Which can then spread to the interior of the car. The potential impact of such a fire is significant, making it crucial to understand and mitigate these risks. It is important to note that the risk associated with EV's is the lithium ion battery itself and not the charging equipment. Despite this, because the charging equipment is installed within the building, this may trigger requirements within the National Construction Code where the EV and charges need to be considered as a special hazard, which requires fire engineers to be engaged as part of the solution. So, should fire be a concern if I'm? Buying an eBay No. However, there is a small but nonzero risk that are faulty or damaged battery pack inside an AV could catch fire, but through mitigation measures the risk can be appropriately managed. AV fires pose additional challenges, such as the battery packs being located beneath a car, which can be difficult to extinguish for both an installed sprinkler system and for the fire brigade. There's also off gas events associated with thermal runaway, which can be challenging to detect for standard detection systems. There's also the potential for reignition hours, days, or weeks. After extinguishing the fire and of course the risk of electrocution. So is charging an EV charging station safe? Yes, you will be safe when charging if you use compliant EV chargers like ocular charges that we've got here. And it's been installed by a qualified electrician in accordance to a US New Zealand 3000 wiring rules. Ocular charges have been certified by international standards like IEEE C 61851 and 62196, which passed rigorous safety tests. The risk of a fire from an EV charger. Minimal and no greater than any other electrical device. In fact, the inbuilt safety devices inside the charger make it one of the safest pieces of electronics installed in your premises. AVSC ensures all AC charges we install has safety current devices such as residual current devices and circuit Breakers and RCD will cut off the power to a circuit if it detects a leakage and goes beyond safety thresholds. Circuit Breakers will cut power between the electrical supply and the charger in case of any overcurrent. Both of these safety devices. Help prevent unsafe operation of the charges caused by insulation or the vehicle itself. The other risk is overcharging the battery. EVs have an inbuilt battery management system that will ensure that it does not overcharge. It does this by communicating with the battery and regulating the battery voltage, current and temperature. By integrating these mechanisms, a battery management system ensures that the safe and efficient charging of the battery, preventing overcharging and extending the batteries life span. The focus for the fire safety strategy should be to limit. Glass spread by containing the fire to the vehicle of origin, evacuating occupants to minimise exposure, supporting fire brigade intervention and consideration of the building structural stability. This can be accomplished with ADP consultings. EV approach of incremental upgrades to the National Construction Codes themed to satisfy provisions as opposed to entirely new or bespoke systems. Automatic fire sprinkler systems are considered one of the most effective methods of limiting fire spread between vehicles. Incremental upgrades are the sprinkler system can provide. Benefits in relation to cooling and wedding of the adjacent fuel load to minimise fire spread out can also increase the design hazard classification of the sprinkler system to be more in line with international standards. A sprinkler systems hazard classification relates to its performance such as water flow rate, area of operation and duration which are all governed by the expected hazards or fuel loads within a space. Also, optimizing the sprinkler placement throughout the car park can minimize the spread as far as possible and remember. Fire sprinklers are only intended to control the fire until firefighters arrive. As well as reducing fire spread, the fire engineering strategy should aim to reduce the risk to evacuating occupants in enhanced detection system throughout the car park can provide early warning for occupants once a fire has occurred. In areas that may be prone to high ambient noise, such as car parks, strobes and visual warning devices placed throughout the car park can enhance the occupant warning systems effectiveness. The fire strategy considers additional risks. And mitigates the risks to firefighters where possible. This is achieved through adequate firefighting equipment and providing information that the fire event may potentially involve an electric vehicle. The first step is ensuring that the fire brigade is aware that there may be an EV file. This can be facilitated by providing an indication of the fire panel and showing EV charging locations and isolators on the building block pans. Automatic and manual isolators shall also be provided to shut off power to the EV charges during a fire, reducing the risk of electrocution. Secondly, reviewing fire hydrant locations and ensuring coverage from multiple hydrants can further facilitate brigade operations by allowing them to fight a fire effectively. Enclosed car parks are typically provided with exhaust systems to extract exhaust gases during day-to-day use of the car park. However, they're not designed for higher temperature smoke and will only operate until they fail during a fire. ADP consulting recommend considering smoke exhaust provisions to improve conditions in the car park during fire brigade intervention. So these include things like. What temperature fans and fire resisting cabling As well as distributing exhaust points throughout the car park. A minimum exhaust rate shall also be specified which is significantly over and above the minimum Australian standard requirements. Finally, due to the risk of reignition, it's also essential that the vehicle is removed from the premises following the fire event. Building management plan should be developed to remove the affected vehicle from the car park following the suppression of fire and also ensuring that there's clearances for tow trucks or the like to access car parks. ABC has adopted advice from the Australian Buildings Codes Board ABC B guidelines and offered cost effective solutions which can help to reduce the risk of AV fires in buildings. Firstly, all our charges reinstall certified by international standards. IC and have the RCMT of approval. Secondly, ABC can provide protective masks, isolation at the charger location or at the fire panel as part of our turnkey solutions to ensure that electrical isolation of all EV charges in the instance of a fire. Vinyl site. Thirdly, EVC can provide signage for your installation to ensure everyone has the information they need during an emergency, especially the fire brigade. Example of this includes locations of charging ports, switchboards and isolation switch gear. In the main switch room. ABC also installs collision protection such as birds and wheel stops to prevent damage to EVs and the charges to ensure safe operation of the vehicle and charger. If Lastly, ESC provides Explorer which is an OCP charger management software which can monitor the charger and detect faults. ABC works with ADP Consulting to implement their fire engineering methodology for accommodating EVs and associated EV charges in both new and existing assets. We work closely to provide a coordinated solution that optimizes the electrical design and mitigates the fire risk. This will depend on several factors, including the compliance pathway, whether there are any existing fire engineering reports, the existing building services design, and the proposed number and locations of EV charges. ADP. Consulting is leading the way in research and industry development of solutions. In addition to our thought leadership papers, our team is actively involved in industry to help develop a best practice guide for the fire safety of EVs in car parks. Thanks for listening. Please reach out to AVC or ADP for expert advice regarding your EV charging solution. Happy charging.