Batteries allow you to store extra energy generated by your solar panel. This can help you stay online if there’s a power outage. In this podcast, Brian Sadler explains the specifics.
John Maher: Hi, I’m John Maher. I’m here today with Brian Sadler, vice president at Solaris Renewables, a solar company in Massachusetts, providing premium solar and storage technologies with exceptional customer service and designing, installing, and servicing solar systems in Massachusetts, Southern New Hampshire, and Maine. Today we’re talking about batteries for your solar system in Massachusetts. Welcome, Brian.
Brian Sadler: Hey, John. Thanks for having me in.
What Are Batteries for a Home Solar System?
John: Sure. So Brian, what do we mean by batteries when we’re talking about a complete solar energy system.
Brian: Yeah, that’s a good point. I mean, that is a very general term, but there is now an entire market geared towards renewable energy and geared towards solar, and they’re referred to generally speaking as ESS or energy storage systems.
And the idea is it’s the ability to store kilowatt-hours of your solar power in your battery and then either discharge them in an outage or during times of low light, evenings, things like that when your solar system’s not producing. And it depends on the market you’re in on how to leverage those kilowatt-hours.
John: Now here in Massachusetts, some extreme weather events are not uncommon. In the winter, we get Nor’easters, snow storms, and blizzards.
Brian: Oh, yeah.
John: Things like that. And then in the summer we get our fair share of lightning, thunderstorms, and things like that, high winds maybe. What are some ways that batteries can enhance the reliability and performance of a solar energy system?
How Your Solar System Works During a Power Outage
Brian: I think one major piece that customers and folks don’t realize is that for safety’s sake, your solar system is attached to the grid as well. So not only for your ability to save money and have energy savings, but also for safety in that when your solar system overproduces, it’s going to push power back onto the grid. And so when the grid goes down, it sends a signal to your solar system to shut off so that you’re not pushing power onto the grid while our line workers are trying to get the grid up and running because essentially you could be electrocuting them and it’s a serious safety concern.
The battery by itself is very similar to a solar panel by itself. It’s not going to do anything. It needs the controls and electronics along with it to interact with the grid, with the home in order to be effective. So batteries, for instance, are paired with…
Each manufacturer has their own transfer switch and controls, which are the electronics and “the brains” of the operation. And what happens, in milliseconds in some cases, when that grid goes down, it’s going to cut the property off from the grid and therefore be operating on the battery. If you don’t have a battery, your solar system is down in the grid. And a lot of folks don’t realize that. They figure, “I got solar, why don’t I just continue to operate?”
John: “If the sun’s out and the power’s down, can’t I just run my appliances off of the sun that’s shining on my solar system right now?” But that’s not the way that it works. The grid actually has to be up in order for it to be working.
Brian: Just so that your equipment sees a signal from the grid, so knowing that it can operate and then, again, for safety’s sake, when that signal is dropped and the grid goes down, we have an outage, it tells the solar system to shut off again for safety sake and for regulations’ sake.
John: You don’t want to be putting that electricity into those lines that are potentially being repaired by people.
How Batteries Improve Reliability and Performance
Brian: So by having a battery with all of the necessary controls, you’re able to isolate off of the grid and in theory, keep your solar system going. But in theory, a perpetually operating home, provided there’s sufficient sunlight and you’re being somewhat of an energy miser, that your solar system is powering the home and then recharging the battery and then at nighttime, you’re working off the battery and draining that battery until the morning time where your solar system comes back up, powers the home, and is able to recharge the battery.
So obviously there’s a lot more nuance in it than that and want to make sure that you’re using your home power effectively to have your essentials. But you can, in theory, use anything you want. Just be smart. You don’t want to go bake a turkey per se when you’re working off the battery. You want to try to make your battery last as long as possible.
John: So just kind of cut down your energy usage to just the most important things like your refrigerator and things like that.
Brian: Be mindful. We tend to give customers the control, so we’re going to give them whole home backup in most cases, with the exception of some high or lows that are going to be either unable to be supported by the battery system, depending on the size of the battery system, or that would drain the battery system too quickly.
But a lot of times, we educate the customer and give them that control, but they want to be energy misers for sure in an outage in order to maximize the solar and the energy storage capacity.
Other Advantages of Solar Batteries
John: Okay. Now, other than powering the home during storms when the grid goes down, are there other advantages of adding battery storage solar set up?
Brian: Yeah, I mean in a lot of states… California for instance, they just had a huge policy shift which changed how solar works with the grid and how you can save money. So what a lot of folks are due now… And this has happened in Hawaii and other states, and here in Massachusetts we have 41 municipal light plants that have, I’ll just call it a weaker solar program so that your ability to save is not as strong.
So by adding a battery and storing your kilowatt-hours from solar in your battery and then able to bring those back in the evenings or again on days when solar is not as productive, cloudy, rainy days, things like that, you’re able to garner those savings that you wouldn’t have gotten by just having solar and relying on the energy savings that you can get from the utility, which in those cases are weaker than we have here in most of the cities and towns in Massachusetts.
John: And when you say weaker, you mean that they’re not giving you as much money on the dollar for the kilowatt-hours that you’re sending back into the grid, that sort of thing?
Brian: Yeah, exactly right.
Consider Net Metering Costs When Deciding on Batteries
Brian: So I don’t want to get too detailed, but net metering is what it’s called. So in effect, when you are pushing power back onto the grid because you’re overproducing more than your home needs, you’re going to be getting credit for that power. Now that generally happens on a monthly basis, but if you’re… We’ll call it right now, our rates in Massachusetts are currently around 40 cents. They just came down from the winter rates, but we’re paying 40 cents, but we have a couple different tiers of net metering at this point, an older and kind of a newer, but if you’re getting back, we call it near retail rate, almost 40 cents, that’s phenomenal.
But if you’re getting back wholesale rate, which might be seven or 10 cents, well, there’s a huge delta there that you could take advantage of by having a battery and being able to generate your own “net metering program” by storing those kilowatt-hours from your solar system and then discharging them back to your house at night. And therefore you’re really a lot more resilient not only to outages, but to the constantly rising rates from the utility.
Challenges of Installing and Maintaining Solar Batteries
John: Okay. What about installing and maintaining solar batteries? Are there any advantages or disadvantages or challenges with that?
Brian: I mean, the challenges are basically unique to each property, so it’s kind of more like what’s going on at the property. So batteries are a finite capacity as well. So if each battery has a certain amount of kilowatt-hours of capacity, and if your usage on a daily basis is well beyond that, well, you just need to install more batteries or more solar, which usually aligns with what the homeowner’s looking to do.
And you want to have a program and system that works for you and generates as much savings and resiliency as you can get. So those two usually do align. We want to make sure that homeowners have heating, for instance, in an outage. So a challenge I would say is that homeowners want to back up everything in their house. We don’t need a hot tub in an outage, so the sauna and the steam in the shower, or…
We’re seeing more and more folks electrified, so EVs and EV charging, heat pumps, these are all really great products and work really well with solar, but they’re a challenge to be backed up because they’re higher load items. So we want to make sure we’re taking a good look at that and not only the individual loads of the home, but also overall in load calculations to make sure that we’re delivering on good expectations and a good system that the customer can rely on. So there’s just some education and some fact finding through that journey, but generally speaking, we can make sure that homeowners have a solar storage store that they can be really happy with and will give them energy security, security in an outage, and some great resiliency as well.
Upcoming Advancements in Solar Batteries
John: And what are some of the latest advancements in battery storage for solar systems? Are there any particular technologies or features that homeowners or businesses should be aware of?
Brian: In our industry in general, for solar and batteries, there is always talk of what’s coming, but what’s tried and true right now are lithium ion batteries. Before these really came to market, folks were using car batteries and they worked great, but you needed a garage full of them. So now lithium ion has a much higher power density, so therefore the product can be a lot smaller.
So I think they’re working on the cells, they keep trying to work on that chemistry. There are some chemistry that potentially have a higher density and coming, but these are things that are being worked through R&D and are probably a little ways out. I think one piece that’s exciting that goes with energy storage are smart panels and ways for homeowners to be able to have more control of their energy usage with the battery and basically elongate the life of the battery.
Basically you have visibility over every circuit in your home, you’re able to shed loads. These things happen automatically. So in an outage, it will drop these high loads automatically so that we don’t, for instance, need to make a high load panel and remove those circuits from the homeowner’s control. We’re able to leave their system as it is and then they’re basically able to have control through automatic load shedding and then individual circuit load shedding through their app. And then they have really transparent monitoring to see how long the battery’s going to last under the given conditions of what they’re using and how much. So I think that’s one piece that’s exciting, a technology that’s really emerging that I would say that goes well with battery technology right now.
Cost of Adding Batteries to a Solar System
John: Okay. What about the cost implications of adding batteries to a solar energy system? Does it make it a lot more expensive when you’re adding batteries into a system? And are there any incentives like rebates or financing that are available?
Brian: Yeah, I would say, what we talked about on another episode as well, is some of those incentives and Massachusetts in particular being really supportive of renewable energy. So there’s no doubt about it that there’s added costs for adding a battery. It’s complex and it’s a big technology that has an additional cost with it. But there are incentives because the state has, to some extent, forced the utility’s hand and the utility has also wanted to garner some control and benefit from these renewable devices that are being installed throughout the state.
So at this time, not only do they qualify through the tax credit. That was really re-clarified through the IRA legislation passed federally last August, so they qualify for the tax credit. There’s also local incentives that some of the major utilities provide for allowing customers to share their access to their battery with the grid, which means that the utility under peak demand events… When it’s hot and humid and the ACs are running and the pools are going, that’s where we see brownouts across the country and some utility disruption.
So what the utility said is, “Okay, if you allow us to have access to your storage, we’ll pay you for that.” So basically there are some really exciting incentives for customers to take advantage of if they’re willing to allow the utility access to their battery under peak load events. And there’s also ways, like it’s an opt-in opt-out program. If there’s a pending storm coming, they won’t be able to pull. So that’s another thing.
The customers are still going to get their resiliency and security by having an energy storage system, but they’re able to access some more incentives that will help pay that system off. So batteries don’t generally generate savings. We talked a little bit about there’s an opportunity in some areas to generate some savings, but it’s more for that backup and that security so that this “payback” is generally challenged, but now with the federal tax credit being defined and these local incentives for the utility, the battery will pay for itself.
Solar Batteries Vs. Whole Home Generator
John: And if you were considering purchasing like a generator system or something like that for your home and you’re getting solar, the battery back up for the solar just makes all that much more sense. And again, you’re staying off of the fossil fuel so it fits right into that system.
Brian: Exactly right. Yeah, that’s exactly right. John, we want to, generally speaking, compare it to a whole home generator. So a whole home generator has significant cost and significant infrastructure that’s required for it to operate. Then there’s generally ongoing maintenance and fuel, where batteries don’t have that.
There’s no ongoing maintenance and there’s no needed additional fuels for the batteries. So it is an upfront cost, very similar to a generator, but actually now there’s mechanisms in place, like I said, the tax credit and local incentives, to actually pay that investment down where a generator is the same upfront investment, but then an ongoing cost on top of that.
Contact Solaris Renewable to Talk About Solar Batteries
John: Right. All right. Well, that’s really great information, Brian. Thanks again for speaking with me today.
Brian: Awesome, John. Thank you.
John: And for more information you can visit the website. It’s solarisrenewables.com or call 781-270-6555.