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Episode 17: The Future of Energy Storage Systems transcript

Trevor Tremblay: Well, there's definitely a few challenges with the battery energy storage. Because of the increased interest in these systems, there are some sellers out there that aren't supplying fully certified equipment, so it's very important for buyers and LECs, who are doing install, to check for the right marks. But those markings aren't as straightforward as a typical certified product, say like an electric vehicle charger. Remember that energy storage systems may not be just one piece of equipment. You may have a battery bank, converter, charge controller, and so on, and if it's not a self-contained ESS, and most aren't, there has to be approval label for the battery storage system. If it's a multi-part BSS, the label should have all the parts listed on the label, indicating that it is battery energy storage system. So typically, they're the model numbers of the inverter, the batteries used, if there's any enclosures required or racking.

Karen Ras: More people and businesses are investing in energy storage systems than ever before. We expect the trend to keep accelerating as electricity costs and new kinds of electricity technology stay top of mind. With more people buying them, that means more installations. This episode gets you up to speed on some of the most common questions and important details to help you stay safe and informed out in the field. Grounded in Ontario is a podcast for you, the province's licensed electrical contractors, master and certified electricians, and offers safety tips, tech, and best practices. Now, let's get grounded. I'm Karen Ras, and I work for the Electrical Safety Authority. Trevor Tremblay is with me again today. How are you, Trevor?

Trevor Tremblay: I'm great, Karen. I'm really charged up to talk about energy storage systems.

Karen Ras: Yes, energy storage systems, or as we often like to call them ESS systems, sometimes BESS for battery energy storage systems. Level-setting for our listeners, Trevor, what is an energy storage system? What does it do? I mean, it's right in the name, but maybe you could rattle off some of the main parts of, one, some of the different types, like residential versus commercial.

Trevor Tremblay: Well, sure. Typically, energy storage systems store energy. We'll be focusing mostly on battery energy storage systems. So essentially, it's a big old battery for your home or business. You can charge it up, and whenever you need the power, you can use it. You can use it for backup power when the power goes out, you can try load-shedding to reduce your hydro bill. It's a very trendy thing to do. Lithium batteries seem to be all the rage right now. Some neighbors have it, so the other one, other neighbors want them too. And the main parts of the ESS typically are the batteries themselves. You can have an inverter, monitoring system, charge controllers, and an enclosure where you can put some of the components in. Residential ones typically are smaller and less complex, and the bigger you have it, the more complex they get, and we're seeing a lot of battery storage everywhere, from residential to commercial to industrial.

Karen Ras: Now, you mentioned saving on a hydro bill. How does an ESS help with that?

Trevor Tremblay: So typically, you can charge your batteries at night, at off-peak hours, and discharge them at peak hours, which would lower your hydro bill. Might lower your bill a little bit each day if you time it right.

Karen Ras: Smart. That makes sense. Now, overall, are you seeing more people get energy storage systems installed?

Trevor Tremblay: They're very popular right now, and they go hand in hand with solar. Everyone's looking to get backup power and reduce their hydro bills. Some areas, we're seeing more than others, typically cottage country, where there's less hydro and a lot more outages. So we're seeing that definitely in there.

Karen Ras: Yeah, I believe we've also seen some utilities install some of those backup systems instead of rebuilding pole lines because it helps with improving reliability. So that brings us to the real meat of the episode. People are getting ESS, installed more frequently, so that becomes a bigger need to understand safety, the big S in the ESA. For those contractors listening, what do they need to know about safe installation and approval requirements for these systems?

Trevor Tremblay: Well, there's definitely a few challenges with the battery energy storage. Because of the increased interest in these systems, there are some sellers out there that aren't supplying fully certified equipment, so it's very important for buyers and LECs, who are doing the install, to check for the right marks. But those markings aren't as straightforward as a typical certified products, say like an electric vehicle charger.

Karen Ras: So on an EV charger, you just look for the Canadian approval mark from an accredited certification agency, but you're saying that's different for an ESS?

Trevor Tremblay: Oh, yes. Remember that energy storage systems may not be just one piece of equipment. You may have a battery bank, inverter, charge controller, and so on. And if it's not a self-contained ESS, and most aren't, there has to be an approval label for the battery storage system. If it's a multi-part BSS, the label should have all the parts listed on the label, indicating that it is the battery energy storage system. So typically, they're the model numbers of the inverter, the batteries used, if there's any enclosures required or racking, that sort of thing.

Karen Ras: Okay. So the main takeaway for contractors here is that it is not a typical certification situation and to be on the lookout for an overall system approval in addition to approval markings on all pieces.

Trevor Tremblay: Correct. The energy storage system will say CSA or any other accredited agency. It may say UL 9540. There's nothing in the standard that says it has to say 9540, but it will say that it's a certified battery energy storage system, and we'll just have one label state in that. And for multi-part BESSs, for example, the batteries will be approved to UL 1973, the inverters will be approved to 107.1, and however the whole energy storage system needs to be approved to UL 9540, and that's whether you're off-grid or on-grid.

Karen Ras: So 9540, the magic number. Contractors, take notice, this is good information to have on hand, especially if people start asking about DIY. Isn't that right, Trevor?

Trevor Tremblay: These are very complex installations, and I've seen a lot of them go very wrong. So it's very important to hire a licensed contractor. It is confusing. The market's changing quickly, and the technology is too, and the products, so it's actually really worth hiring a licensed electrical contractor. So, yes, contractors, if people start asking you about doing it themselves, you should impress upon them the complexities and the certification requirements and the regulations around placements. It's so easy for one thing to go wrong, and the best thing you have is a bunch of useless and expensive equipment, and worse, you burn your house down.

Karen Ras: Yikes. Not worth a DIY experience like that. All right, keeping on the topic of ESS installation, since it's a job that seems like it will only get more popular, what else should contractors keep in mind?

Trevor Tremblay: There's a few things. There's the how, especially with wiring and working space, and the where, is good to know as well.

Karen Ras: All right, let's go through each of these one at a time. Wiring, what's the deal here?

Trevor Tremblay: Well, for a multi-part ESS, one thing is the conductors have to be fine strand cables when connecting the batteries. We often see welding cable being used as it's not approved as an electrical conductor for the most part. It's not voltage rated and stuff like that, but for some reason, we see it everywhere. So remember, that has to be approved cable and it has to be a fine strand. And from the batteries to the inverter, you're limited to three meters in length of conductor, and any longer than that, you'd have to transition to Section 12 Wiring Methods, which is essentially armored cable, non-metallic sheathed cable, and raceways, that sort of thing.

Karen Ras: Okay. Got it. Fine strand cable, not welding cable. Good to know. Next, you spoke about working space. Tell us more.

Trevor Tremblay: Well, the installer needs to make sure there's enough room to get away from the equipment. If there's a hazard, that thing starts to catch fire or arcs, you want to safely clear the area. That's what the working space is for. So you can get to the exit without crossing any fire or shock hazards. You do need a minimum of one meter secure footing in front of that equipment, and the minimum size of the room is one meter plus the equipment depth with headroom of two meters. And the manufacturer may also reduce the distance between the battery energy storage system as parts of the certification of the UL 9540.

Karen Ras: So no installing an ESS in a tiny crawl space. Speaking of where to install them, there certainly must be requirements about exactly where ESS can and cannot be installed, correct?

Trevor Tremblay: Correct, as well as separation distances from multiple battery banks, if you're doing that. All are related to safety, mostly to limit fire risk. So for multiple battery banks, there must be a one-meter distance apart from them, or the manufacturer can actually reduce that distance. If they don't say anything, it's a meter. If they say what distance it is, you can use the distance in the manufacturer's instructions. If they reduce that one meter, that means they've been tested to make sure that one battery bank, based on that distance, won't catch the other battery bank on fire.

Karen Ras: Okay, one meter is the ticket, in this case, unless otherwise specified, at least one meter.

Trevor Tremblay: Yes, that's correct. Now, turning to where you can install an ESS. So in dwellings, ESS can be located in a garage, detached or attached, or be installed in a dedicated room with specific requirements. It can't be installed in sleeping areas, your bedrooms or rooms that open directly into the sleeping areas. It has to have a door equipped with a self-closing device, has to be enclosed with a minimum construction of ceilings and walls finished with gypsum board, and the floor is finished with lumber sheathing, and the rooms do have to have an interconnected smoke alarm.

Karen Ras: What about in an apartment building or condominium?

Trevor Tremblay: So for a building containing multiple dwelling units, residential occupancy, the ESS again must be in a dedicated room or utility room. The room may be within one of the dwellings or in a common area. In addition to the requirements I mentioned earlier for dwelling units, it needs to be a one-hour fire rating and cannot be located beneath any exit required by the building code.

Karen Ras: And are the rules similar for commercial property?

Trevor Tremblay: Similar, but they're definitely more flexible. The requirements we spoke about with the residential properties were created for the safety of people living in these dwellings where the batteries were installed. People don't live in commercial properties, so the risk is a lot lower. There are some spacing requirements from windows and doors and points of egress, and there aren't any size restrictions for fire-rated rooms, but will still require the system to be overall certified to 9540.

Karen Ras: Clearly, a lot of thought has gone into exactly where an ESS is most safe to operate depending on the type of property. Should people be at all concerned about how safe an ESS is, and are they really such a big fire hazard?

Trevor Tremblay: So if it is a certified system, installed according to the Ontario Electrical Safety Code and the manufacturer's requirements, there's nothing to be especially concerned about. In the event of a fire unrelated to the ESS breaks out, it's good to understand how the ESS poses an additional risk since battery fires aren't the same as, say a wood fire, and water will not work on them.

Karen Ras: Yeah. How do you deal with a battery fire if water doesn't work?

Trevor Tremblay: Definitely get the firefighters involved. They are the experts. Either you just let it burn itself out, or sometimes they bury it in sand and wait for it to burn out. Either way, call the fire department.

Karen Ras: And don't throw water on it.

Trevor Tremblay: The water won't do anything on the batteries, but it might contain the fire from spreading to the rest of the house.

Karen Ras: Another related topic we see a lot with the ESS, lead-acid versus lithium-ion batteries. Do you have any insights from the field or for contractors with those?

Trevor Tremblay: Lithium battery banks are much more popular and store more energy, but they have a higher risk of fire, and remember that the whole system has to be certified to 9540. Lead-acid batteries generally can carry less risk, provided they're properly ventilated and usually don't catch fire. We typically only need to ensure that they're in a ventilated area and with proper maintenance, they're pretty much trouble-free. They also store less energy compared to lithium-ion, and some lead-acid batteries don't require ventilation.

Karen Ras: Interesting. Okay. On another related topic, you said that ESS go hand in hand with solar. Can you tell us a little bit more about that?

Trevor Tremblay: For the most part, it's a great system. You charge the batteries with the solar whenever you can, discharge either during peak hours or at night as needed. In the long run, the idea is to save money, plus it acts as a backup system. A solar array plus ESS is especially popular in remote locations, and people have it set up where essentially they use it as the utility as a backup, so the solar and batteries runs all a dedicated panel throughout the day, and then only need the utility when required.

Karen Ras: That all makes sense. Any insider tips for contractors dealing with solar and ESS installations?

Trevor Tremblay: With those setups, there's a lot of inverters are functionally grounded now, so essentially, which means that they don't require any additional grounding. Do you have one reference point usually at the utility service? So as a contractor, you don't need to ground these ones anymore, as long as they're all bonded together, and you can always rely on the manufacturer's instructions. They will let you tell where the grounding is required.

Karen Ras: So we covered battery types and solar. There's one more hot topic related to ESS. Can you guess what it is?

Trevor Tremblay: Electric vehicles?

Karen Ras: Yeah. How did you know?

Trevor Tremblay: I read the notes.

Karen Ras: Of course, of course. So what do EVs and ESS have in common, or how are they related?

Trevor Tremblay: Well, when it comes to safety and installation, there are similarities. Certification markings and proper procedures are always important when dealing with electrical equipment, be it an ESS or an EV charging station. Charging an EV might be another reason to have an ESS, backup charging in case the power goes out, and you see some ESS inverters coming out with EV charger systems built-in.

Karen Ras: Oh, so you'd plug the car right into this ESS?

Trevor Tremblay: Yeah, there's an output for the charger on the inverter. So essentially, yes, charge right from the ESS, so the solar, if you have it.

Karen Ras: That sounds very convenient.

Trevor Tremblay: And it could make the installation easier for the contractor too. Definitely less work. Installing one piece of equipment instead of two, and you have your EV charging system as well.

Karen Ras: Good to know. All right, we have time for one last question. This one is from one of our listeners, Kevin from Woodbridge. He is a pool contractor. "Am I required to bond the clear deck aluminum cover that goes up to extend the pool cover?"

Trevor Tremblay: Good question, Kevin. The answer is yes. The aluminum cover on the unit must be bonded with a minimum number of six copper. It must be a fine strand because as you know, those lids go up and down, and if you used a regular copper conductor, it would break off.

Karen Ras: All right, that's a wrap on energy storage systems. Thanks again for joining us, Trevor.

Trevor Tremblay: Well, thanks for having me. I'm really charged up to hear this episode and future episodes.

Karen Ras: And thank you to listeners for sending in these questions. We want to hear from you, so please email us at podcast@esasafe.com. We're open to topic suggestions, questions, and comments. Make sure you subscribe on any platform where you get your podcasts so that you'll get notified about our next episode. Until next time. Be safe, work safe, and stay grounded.