Although energy storage adoption is accelerating in the residential and utility-scale markets, installing batteries on commercial-sized solar projects is not always an easy process. There’s usually a concern about space — whether there’s enough room to site a large battery at ground-level or if it’s safe to house enough storage capacity in a special room inside a building. The ability to add-on storage as utility rate programs change is also not as straightforward when it comes to permitting and the location of commercial storage projects. The market depends on specialized engineering companies to get solar + storage projects sited.
Yotta Energy is trying to change that. First making news in 2018, the panel-level storage company is going through real-world testing and finally plans to launch its SolarLEAF product in Q2 2022. SolarLEAF is a 1-kWh lithium-iron phosphate battery that sits behind solar panels while also acting as ballast. If solar installers are familiar with microinverters, power optimizers or other module-level power electronics (MLPEs), they can attach a SolarLEAF battery. And since it’s a high-functioning MLPE itself, no additional permitting is needed to add panel-level energy storage.
With the upcoming product launch, Solar Power World talked with Yotta Energy CEO Omeed Badkoobeh about the SolarLEAF’s functionality in the commercial solar market.
SPW: Why has Yotta Energy focused on the commercial solar market?
Badkoobeh: We’ve been in a deep dive in this market for four years now. We understand all the pain points and hurdles. The biggest competition today for any energy storage is doing nothing. Most customers are requesting energy storage, and most developers and installers want to talk customers out of energy storage. Energy storage is extremely complex. You have very specialized companies that exist today that are hyper-focused on energy storage. They have moved to only doing really large systems because of cost factors and because they can’t replicate it from building to building.
Our theory is very much like module-level power electronics in general. They weren’t less costly than inverters, they just provided more value because of simplification. We do the same thing for energy storage. We bring more value because of the overall simplification. If you’re a C&I installer and you can deploy solar and you can install a ballast block, you now can install energy storage. That’s how simple we make it.
Why did you choose lithium-iron phosphate (LFP) for the SolarLEAF’s battery chemistry?
We’ve been big on LFP from Day 1, before it became extremely popular. It is far safer than any other form of lithium battery, and the cycle life is higher. The downsides of LFP compared to NMC or NCA is that it’s slightly heavier because of less specific energy, but that was part of our direction of going into the C&I market where our battery serves as a ballast weight.
Why did you decide on a standard 1-kWh offering?
We have our unique thermal technology [which maintains batteries at their preferred working temperature range (70-100°F)], but it does take a bit of space and mass, so we wanted the product to be at a point in which it can easily be carried by a single installer and be mounted. In order to do that, the limitations we settled on was 1 kWh. It’s also very easy to design. When you’re looking at how to design storage, it’s easy to say you need 50 SolarLEAFs for 50 kWh. We have our roadmap and are working on higher capacity units. We’re very aggressive on driving down costs, and one of the quickest ways to do that is to make a higher capacity unit for our next-generation products.
You’re offering a Dual Power Inverter with the battery, essentially a white-labeled APsystems dual-module microinverter.
APsystems is our OEM partner. They build the microinverters for us on their platform very specific to our needs. We call it the Dual Power Inverter because it’s designed to work interchangeably with both any PV module and our storage device. You can deploy a project today with just the inverters and we call it storage-ready. Then you can come back at any point and add energy storage.
We’re very big on the microinverter architecture because it’s also a safety thing. Given the fact that the entire system is low voltage, it’s very safe relative to a high-voltage DC string system. The barriers for microinverter entry into C&I have always been cost, but we’re in the market today with this inverter at a price point we think is highly valuable and brings a lot of value against taking a string inverter and then having to add rapid shutdown devices.
If you’re using a dual-module microinverter, does each SolarLEAF battery also work with two solar panels?
We design the SolarLEAF to take two inputs of a module. Where it gets tricky is the landscape of modules is ever changing — one moment 450 W is the peak, the next you have 650 W. We work with every standard module today with the exception of some high-voltage 96-cell modules.
Where does the battery sit in the project’s wiring?
It’s a DC-coupled system. We call it PV-coupled. The battery sits between the PV module and the microinverter input. The batteries absorb straight from the PV module. [DC-coupling] is the highest efficiency because you’re only converting DC to AC one time. We’re using the same inverter as the PV module, whereas most energy storage today is AC-coupled. You’re not going back and forth between DC and AC and having losses.
Is Yotta Energy a battery company or an MLPE company?
We see ourselves as more of a technology company. I think to be successful in today’s market you need to provide a solutions-based approach. The days of the installers and developers having to deal with multiple vendors to solve the same problem or solution are diminishing. They hate having to buy an inverter from this company, battery from this company, rapid shutdown device from this company. We see ourselves very much morphing into being a technology leader in this C&I market.
You’re often compared to JLM Energy’s failed panel-level storage product from a few years ago. What makes Yotta Energy more successful?
Tesla was the third company to attempt electric vehicles. Any new technology takes a well-thought-out team and careful execution and timing. We had been developing our technology way ahead of the announcement of the JLM battery. We always knew that you have to prove the physics of how this battery can last on a rooftop. If you can’t do that, there’s no point of pushing this product out yet. That’s the reason why other MLPE companies maybe haven’t attempted this format. We worked really hard over the last three years of perfecting this thermal technology that makes this product a reality.