‘We like its ability to scale’: Honeywell targets gigawatt-scale storage opportunity with flow battery

You may have seen from our coverage yesterday that the company is keeping the exact chemistry of the battery under wraps, but we do know that it uses non-toxic and abundant materials, is designed to be recyclable and offer up to 12 hours of energy storage duration in a durable package over many years of use. 

A 400kW system is being installed at US utility Duke Energy’s North Carolina testing facility in 2022 and then a 60MWh pilot is expected to go ahead the following year. 

Honeywell Sustainable Technology Solutions (Honeywell STS) vice president and general manager Ben Owens spoke with Energy-Storage.news’ Andy Colthorpe on the eve of the announcement.

It must be exciting to be telling the world about the flow battery after developing it in ‘stealth mode’ for a number of years. How about introducing it to our readers?

Also, we understand that this product has been developed through Honeywell Universal Oil Products (UOP), whereas your lithium-ion battery storage systems and services offerings have largely been delivered through Honeywell Process Solutions. 

We’ve been working on it for a few years…we got interested in this space, we saw a core need for a battery that’s longer duration, a utility-scale battery that uses non-rare earth elements. We have a fundamental belief that utility-scale batteries have got to use a non-rare earth element.

As for why Honeywell UOP for flow batteries: well, a flow battery looks a lot like a [power] plant, just on a lot smaller scale. You have the flow of material, just like you have in an oil or gas petrochemical plant, you have ion exchange, you have the need to be fundamental in chemistry and molecular science, which is UOP’s core value proposition to the market. 

And you have to be fundamental in membranes. We’ve been putting membranes in the market for 30 years, we have our own membrane facility, we test and launch our own membranes. So the combination of those things allowed us to develop in the space. 

We’re going to be bringing together the management and process control capabilities of Honeywell Process Solutions, and kind of the chemistry and know how, of UOP on the battery side, to launch this battery. 

Can you reveal more about the technology? When most people hear ‘flow battery’, they think of vanadium electrolytes and there are other types that use iron electrolytes or zinc bromine. 

We’re not talking about the exact chemistry but it is a non-rare earth element. It uses easy to source materials, and we really like its ability to scale up and down. The characteristics of a flow battery, I think really lends itself well to the utility industry.

I will tell you, it’s a non-rare earth element. So that gets rid of vanadium, which is usually people’s first question!

We like the chemistries in that [flow battery] space. You don’t get the same density [as with lithium-ion] but really, this is about cost.

At the utility-scale, density is not your primary driver. We really liked that space for its cost profile, and for the ability not to be coupled with a supply chain that could run into challenges that could swing drastically. 

How about the development process? We’ve seen flow battery technology adopted by the renewable sector, but more broadly, the energy tech sector, from the early groundwork by people like NASA and academics decades ago. How much of the development started from scratch with what you guys are doing and what’s the process been like? What have been some of the challenges that you’ve overcome along the way?

We started from scratch. We’re really good at optimising chemistry. So if you look at UOP’s core history, we’re fundamental in molecular science, we’re fundamental in the chemistries.

Not to say we haven’t had our experiences with all the challenges, you have with a flow battery around leakage. That’s something we’ve been fundamental on, really making sure we hit the segment correctly. That’s why we really like our partnership with Duke — it’s really dialling into what the utility segment’s going to be looking for.

In terms of what utilities will be looking for, over the last few years, as battery storage has come into the market, at Energy-Storage.news we were initially mostly reporting on projects with perhaps 15 minutes of storage, typically doing frequency regulation. That’s crept up — or perhaps even jumped up — to one, two-hour systems and now we’re at the point that four-hour is probably the most common among projects announced in the US. 

Where and at what point do you see the need for longer duration battery storage coming in? 

I think that four hours is really also a dependency on the lithium-ion side. As more wind and solar come on the grid, we hear from utilities and we see in our own modelling, eight to 10 to 12 hours [duration] is really going to be the driver of energy storage over time. That full 12 hours is what we’re going to need.

You also need some seasonal storage. That’s most likely going to be accomplished by hydrogen. But we see in our modelling that you can get to more than 50% wind and solar on the grid with a battery that runs 12 hours. We think this is the spot to develop in. 

You can’t have one before the other: what’s going to go first, solar and wind or batteries? No, the answer is that they’re both going to go together. 

We see the forecasts for wind and solar, we see the direction of wind and solar [deployment], but that’s going to hit an upper bound if batteries don’t follow us shortly. I think we’re not late, we’re not early, we’re kind of right where we need to be!

One other aspect of flow batteries that flow battery companies and their investors often like to impress on the market is safety. While I think it is widely accepted that there is less fire risk and therefore less mitigation required for flow batteries than lithium, I’m yet to see that cited very often as a reason a utility is choosing to procure flow batteries at scale…

As Honeywell, we’re in both spaces. We do process control and management for lithium-ion [battery storage]. Lithium-ion batteries, while they’re more energy dense, they have to be greatly spaced out because of the safety concerns: they need cooling, they need fire prevention and gas detection systems, they need a lot of control. 

So I think safety is a core element, but it also comes down to cost. 

If you don’t have to deploy the same fire and gas mitigation systems, if you have fairly safe systems, you don’t have to have the redundancy that controls the process. 

So, I see this as more a cost argument. Because both these batteries, lithium and flow, will deploy safety systems that are inherently safe, and the end user will demand it. But I see it more as a barrier on lithium-ion to go to a larger scale, this gigawatt-scale, that these large-scale deployments need.

What can you tell us at this stage about the pilot deployment with Duke Energy, which begins next year? 

Duke Energy is more aggressive in the emerging technology area than many other utilities. We’ve been engaged with them for over a year. 

From the late prototype stage, we’ve been working in their feedback, asking them where they see the market, where they’re looking to develop. They’re obviously testing multiple chemistries — we see them as an ideal partner, because they have this kind of micro grid centre, where you can do real world testing at their Mount Holly facility. 

They’ve really been a partner helping us as we’re scaling up. There’s challenges we run into and they’ve been great on the feedback side.

What we really like about our flow battery is its ability to scale. As a company, we know how to build large-scale plants and as I said earlier, this looks less like a battery and more like a plant in many ways. 

We know how to do balance of plant, we know how to scale up. We will go from a very small pilot plant to a large-scale unit with nothing in between. We’re very comfortable if we prove out the engineering, we can prove out the cell design, we understand what we had to prove out — what scales and what doesn’t. That’s just kind of what we do. 

If you look at what we’re deploying around the world today in the oil and gas market, that’s fundamentally our UOP business — the ability to scale. 

That’s another one of the characteristics we like in this battery: we can use our core competence in scaling, to rapidly increase the size once we’ve proved out the the chemistry, the cell design, the flow dynamics, everything about round trip efficiency.

Then we can go very big, very quick.

The idea of really large-scale long-duration energy storage is exciting. We’ve seen flow batteries put in recently on industrial or remote microgrids in the past few years, as well as a few much larger megaprojects in China and Japan at the other end of the scale. Do you see a market developing for flow batteries at smaller as well as the larger scale?

I think we’re kidding ourselves if we think one battery [technology] is going to win out here. There’ll be multiple batteries, multiple market segments, multiple use cases. Industry data indicates there will be a US$13.7 billion market for energy storage with 115GW coming online by 2030. 

There’s room for multiple players, there’s a need for multiple players. You have shorter duration peak shaving, you’re going to have larger scale, you’ll have seasonal storage. So I do think there’ll be multiple batteries that play into the US grid and worldwide grids.  

It seems to be commonly accepted by the energy storage industry that there will be multiple technologies, particularly for long-duration. With the vanadium flow battery, one constraint appears to be the availability of raw materials and electrolyte processing capacity, at least in the short term. While its ingredients are still a closely guarded secret, what can you tell us about Honeywell’s manufacturing strategy for the flow battery and its supply chain? 

It’s readily abundant material for the entire use of the battery. So there’s no need to build a specialised supply chain: it’s abundant, non-toxic, environmentally safe material. 

On the manufacturing side: we’re not ready to talk about it yet. We’re looking at a couple different options. Honeywell, is a core manufacturer, we’re talking about exactly how we want to scale up there. So there are some decisions to come, we’ve not made a decision exactly how we’re going to put it together.

Part of the great success of lithium-ion has been to do with how the technologies have become readily bankable. What are some of the things that need to be verified and figured out in the pilot and testing process for the flow battery over the next year or two? 

The Battery Innovation Center in Indiana is going to be doing a lot of testing. There’s been a lot of leakage issues with flow batteries — we believe we’ve solved all those. 

They’ll be looking at the efficiency, the duration… the value propositions says ’20-year lifetime,’ so we’re going to be looking at degradation — we believe we’ve solved that. 

Bankability is a fundamental issue in the market, but an area we’re very comfortable with. 

If you think about a refinery or petrochemical plant, we’ll write a guarantee on the technology that fundamentally backs the design, building, construction of a billion dollar plant. So it’s an area that we’re very comfortable: looking at the chemistry, looking at its lifetime and writing a guarantee that you can take to the bank, or that a project developer can take to the bank and go build a project off of. 

That’s something else we think we bring to the market, understanding of the battery, understanding of its chemistry, understanding the degradation, and then the fact that we’ll stand behind it or wrap it in a control system, and will stand behind it for its 20-year life.