Frozen turkeys are thermal batteries

Balancing grid supply and demand one pump and compressor at a time.

I went to San Diego two weeks ago for DistribuTECH as part of our ongoing investigation into the industrial Internet. DistribuTECH is a very large conference for electric utility operators in the U.S. and while I was there ran into Keyvan Cohanim of Enbala Power Networks. We had an interesting conversation, the upshot of which was my realization that given the magic of absolute values, as far as the grid is concerned, slowly warming frozen turkeys are thermal batteries.

Enbala’s business is conceptually simple. They use information to optimize the match between electrical supply and demand to help utilities avoid capital expenditure in under-utilized peak-load generation assets. Then they share those supply side savings with the participating loads. The deal is simple, let Enbala control your loads within your process constraints, and you’ll earn additional revenue. At the risk of gross over-simplification, they are sort of like an Uber or AirBnB of the electrical grid, but made interesting by the complexity of constraints and the fact that it all has to happen in real time.

They’ve done a video that explains it, and it’s actually pretty good. But in short, they improve on simplistic and disruptive load shedding and load curtailing approaches by modeling a load’s internal processes and constraints, instrumenting them, and then taking control of major loads within those process constraints. They do this such that the load owners won’t even notice it’s happening. Things still stay cold enough, or full enough, or whatever enough, but within the process margins they might be chilled, filled, or whatever’d a little bit earlier, later, faster or slower to better match hundreds of loads across the grid with current supply conditions.

For example, if the wind picks up and some turbines get to spinning, Enbala can go around to their participating loads and start some pumps to fill some tanks, or start chiller compressors to cool things down. Conversely, if generation is taxed, before starting an expensive peak load plant, utilities will ask Enbala to signal a downshift in pump speeds, delay compressor starts, etc. This is where slowly warming frozen turkeys may be allowed to get a little bit closer to their maximum allowed temperature. And not running a compressor in this case is identical to starting a generator, or perhaps more accurately, discharging battery that was charged at the lower base-load per-kilowatt rate.

Which made me think, who needs giant expensive inertial batteries to stabilize a mixed grid of base load and sustainable power options, when you can just freeze some turkeys?

I like this story because it highlights two important and related principles of the industrial Internet. That information can be traded for capital expenditures and assets, and that those optimizations get better as more stuff participates in the optimization.


This is a post in our industrial Internet series, an ongoing exploration of big machines and big data. The series is produced as part of a collaboration between O’Reilly and GE.

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