Jonathan Katz, executive editor of Chemical Processing, recently spoke with Thomas Kwan, an energy transition expert at the Schneider Electric Sustainability Research Institute, about his most recent Energy Saver column for Chemical Processing, titled "The Flexible Chemical Plant: Scheduling Energy Use Without Sacrificing Throughput." Kwan, whose official title at Schneider is global vice president of strategic innovation and industrial ecosystems, wrote about how electrified compressors, separations and utilities can behave more like power brokers whose price refreshes every hour. He noted that plants running through a price spike are paying for steady-state, continuous operation they may not need, and he suggested that, to save energy, they must consider operational flexibility itself an energy asset. Kwan asked readers whether they knew which loads in their operation can move by minutes or hours, what that movement is worth under their energy tariff, and when product commitments, catalyst constraints or safety margins erase the benefit before it reaches the ledger.

He noted that common process targets for flexible operation include retiming batch starts and cleaning cycles, drying and milling campaigns, refrigeration precooling, electrolysis load and noncritical utilities. Intermediate tanks, product inventory, thermal batteries and spare train capacity also can act as buffers that decouple production from the grid, according to Kwan.

Here's what he had to say.

Transcript

Edited for clarity.

Hi, Thomas. Today we're talking about your Aug. 11 Energy Saver column, "The Flexible Chemical Plant: Scheduling Energy Use Without Sacrificing Throughput." In your column, you talk about leveraging dynamic pricing from utilities, and you mention that it's important to map a plan before investing in software tools. What, ideally, should that mapping plan look like?

Map A Plan

Thomas: Yeah, thanks, Jonathan. As we mature technologies for the chemical sector on flexibility, it can be intriguing to jump to the latest and greatest tech. But I put that in the article to say: Pause, make sure you know where you're at in your own plant, and then start to move toward the appropriate technology adoption. When you think about mapping your plant in terms of where the opportunities for flexibility might be — plants are so integrated, and there are so many dependencies — you really have to start to look at where your electrical and thermal duties sit and where those can be shifted over time. Depending on that integration and those duties, you also have to think about reliability and safety. So when you're mapping your plant, it's less about this operation versus that operation, and more about the attributes of the flexibility, what can be possible and, of course, their dependencies within your plant.

Jonathan: In your column, you also explained that "the optimizer decides" is not an acceptable operating philosophy. Can you expand a little more on that point?

Thomas: Yeah, sure. When we think about flexibility, again, we position it as an energy asset. So when you think about an asset, you think about who is ultimately responsible for it and the safety of its operations. When I think about a plant's architecture, the example I gave in the column references a day-ahead optimizer for load trajectories and then an intraday economic layer that reacts to real-time energy prices. You would consider this optimizer a supervisory layer, not an authority layer. Outside of that economic optimization against grid pricing, there are, of course, regulatory controls — and safety, I'll say that again. You have your interlocks, your relief systems and operator authority, and those sit outside that. So that's one thing. The other thing is, frankly, the primary objective may not be maximizing these lower economic gains. It could actually be another objective, like maximizing yields. So depending on your use case, your optimizer may or may not be giving you the best way to operate your plant.

Depending on your use case and the maturity of your flexibility optimizer, a material shift in your operations may not justify the gains — or, even worse, the optimization is not practically attuned to your plant. When I say practically attuned, I've seen many examples where, when studies are first launched and modeling begins, the models recommend impractical or illogical practices for very little gain. I've seen optimizers recommend tens of charge-and-discharge cycles from a battery in a single day for less than a percentage point on energy cost. Funny behavior like that can be engineered out, but that still leaves safety issues, your site context and, like I said, your plant objectives. You may want to be maximizing yields at that particular time for a variety of reasons. It could be customer relations, or it could be things that are strategic to your company, and not necessarily day-to-day flexibility based on the economics alone.

Dynamic Pricing From Utilities

Jonathan: You also talked about dynamic pricing from utilities. Is there anything chemical processors, or process manufacturers in general, should know about that? Is there any kind of collaboration with the utilities that goes into this?

Thomas: That's a question about where we're going with the bigger picture on energy and with grid collaboration. If you're looking at flexibility, you could have benefits and advantages for yourself and for your business, but there are also ancillary benefits to the community. If you can shed some load during peak hours when the grid is under strain, that unlocks capacity for the grid itself. Those types of advantages are useful for you if you can optimize that flexibility accordingly, but they're also useful for the grid operators and the community your plant is in. That's less about today and more about tomorrow and where we're going, given the rise in electricity demand and the time it's taking for grids to build out the right infrastructure. Indeed, chemical plants can be good collaborators with grid operators, enabling flexibility so that capacity can be unlocked.

Jonathan: Thomas, this has been great insight into your latest column. Is there anything else you'd like to add on the topic that you maybe didn't have a chance to address in the column?

Thomas: Certainly, for chemical plants, the idea of flexibility has been around for a while, and in fact, it's been realized in a number of different ways. But what's moving now is, one, the rise in electricity demand and the benefits you get from electrifying your processes, and two, flexibility outside the chemical sector. We all hear a lot about data centers and their flexibility coming into play. Buildings are another part of economic growth where energy flexibility is starting to come into play. So from the bigger picture, I would say the chemical sector is more mature in understanding flexibility and more readily able to execute it. But other sectors adjacent to us that are connected to the grid are also looking at flexibility. So it's an interesting opportunity for the chemical sector to lead the way in how to handle that governance and those ecosystems on energy flexibility.

Jonathan: Thomas, I want to thank you for taking the time to speak with me and the Chemical Processing audience. We look forward to the next Energy Saver column, which will appear on chemicalprocessing.com in early October. So stay tuned.

Thomas: Thank you very much, Jonathan. It was a pleasure.