Jul 1, 2022 · 46m · catalyst
How to Save a Planet: Spark Tank! How Do We Solve the Energy Storage Problem?
Daniel Ackerman · 13m spoken Alex Blumberg · 10m spoken Shayle Kann · 8m spoken Dr. Leah Stokes · 4m spoken Curtis VanWalleghem · 40s spoken Len Green · 37s spoken Dr. Cristina Prieto · 11s spoken Carter Wall · 0s spoken
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gold bands on the timeline = statements, start to end. Hover to read, click to jump. CC turns on captions
In a crossover episode structured as a 'Spark Tank' game show, energy experts evaluate three non-battery, long-duration energy storage technologies—pumped hydro, compressed air, and molten salt—to determine the most viable solutions for balancing a fully renewable electric grid.
How this conversation actually went
Every chapter scored 0–10 on four independent dynamics. Hover any point for the reasoning behind the score. Shayle holds 21.2% of the talking time here. How this is scored →
Shayle as informed peer 3.8 Guest teaching 2.2 Guest disagreement 0.5 Shayle pushing back 0.6
speaking balance: gold is Shayle, purple is the guest (3 minute bins)
Sharpest disagreement ▶ 5:38 Daniel Ackerman dismisses the battery-only assumption
Ackerman playfully rebukes Blumberg's assumption that batteries alone will power the entire grid as a 'rookie assumption' and details resource limitations.
Hardest push from Shayle ▶ 41:20 Shayle pushes back on molten salt due to toxicity and corrosion risksShayle challenges the uncritical enthusiasm for molten salt by emphasizing its corrosive nature, toxicity risks, and permitting hurdles.
Biggest teaching moment ▶ 32:09 Dr. Prieto explains molten salt thermodynamicsDr. Prieto and Ackerman educate the hosts on how nitrate salts remain molten past 500°C without exploding or boiling away.
Shayle holds their own ▶ 37:25 Shayle articulates the decarbonization value of industrial thermal storageShayle demonstrates authoritative domain expertise by explaining how storing electricity as high-temperature heat directly replaces fossil fuels in heavy industry.
the scores for every segment, with the reasoning behind each
| Chapter | Topic | Shayle as informed peer | Guest teaching | Guest disagreement | Shayle pushing back | Why |
|---|---|---|---|---|---|---|
| Shayle Kann Introduces the Spark Tank Crossover Episode | 0 | 0 | 0 | 0 | Solo host intro by Shayle Kann setting up the crossover episode with How to Save a Planet. As a monologue, all interactive metrics are scored zero. | |
| Envisioning a Fully Renewable Future Electric Grid | 3 | 4 | 1 | 1 | Alex Blumberg and producer Daniel Ackerman playfully discuss the grid of the future. Ackerman corrects Blumberg's assumption that batteries alone can solve the entire grid storage challenge. | |
| Introducing the Spark Tank Game Show Concept | 2 | 1 | 0 | 0 | Blumberg and Ackerman outline the Spark Tank format and introduce the panel concept, followed by a mid-roll ad read. | |
| Meeting the Spark Sharks and Allocating Capital | 3 | 2 | 1 | 0 | The panel of judges (Shayle Kann and Dr. Leah Stokes) are introduced and given ten million fake dollars each to allocate, exchanging light banter about Shark Tank formats. | |
| Pitch 1: Pumped Hydro at Northfield Mountain | 2 | 3 | 0 | 0 | Daniel Ackerman presents the field report from Northfield Mountain, explaining the mechanics and scale of pumped hydro storage. | |
| Judges Evaluate Pumped Hydro Storage and Geography Limits | 7 | 2 | 1 | 2 | Shayle Kann breaks down the linear scaling cost of lithium-ion batteries compared to pumped hydro, while Dr. Leah Stokes notes severe land and water resource constraints. | |
| Pitch 2: Hydrostor's Compressed Air Energy Storage | 2 | 3 | 0 | 0 | Ackerman introduces Hydrostor's compressed air energy storage technology with audio clips from CEO Curtis VanWalleghem. | |
| Just Transition Potential and Evaluating Compressed Air Storage | 6 | 2 | 1 | 1 | The judges evaluate compressed air storage; Shayle Kann highlights the fundamental engineering challenge of heat management during air compression. | |
| Pitch 3: Dr. Cristina Prieto on Molten Salt Storage | 2 | 4 | 0 | 0 | Ackerman features Dr. Cristina Prieto explaining molten nitrate salt thermal storage, its 500-plus degree operational ceiling, and high efficiency. | |
| Evaluating Industrial Heat Applications and Thermal Storage | 8 | 1 | 0 | 1 | Shayle Kann provides deep domain insight into industrial heat applications, citing Rondo Energy and highlighting that industrial heat generates massive emissions currently reliant on fossil boilers. | |
| Mid-Roll Advertisements: Bloom Energy and Engie | 7 | 2 | 1 | 2 | The judges allocate their fake investment capital; Shayle splits his between compressed air and molten salt while flagging corrosive safety challenges, and Leah commits all funds to compressed air. |
Statements from this episode (14)
Ackerman: Current battery tech is too costly and resource-constrained for entire grid
“But with our current battery technology, it would just be way too expensive To back up the entire electric grid. Plus, it would require more materials like lithium and cobalt than we have sitting around right now.”
Stokes: Energy storage remains the key missing piece in clean energy
“What I learned in that course was that the most important gap in terms of what technology we had was storage. This was the missing piece in the puzzle. And it's been 12 years, and it still seems to be a missing piece”
Kann: Energy storage has more tech innovation than almost any climate sector
“I mean, there's probably more going on. From a technology standpoint in energy storage than maybe any other space in energy tech or climate tech, because it crosses over. I mean, we're going to talk about a bunch of technologies to store energy on the grid. Bu…”
Ackerman: Northfield Mountain pumped hydro can power 1M homes for 8 hours
“Len told me that when the reservoir at Northfield Mountain is pumped full of water, it can be used to power about a million homes for eight hours.”
Ackerman: Northfield Mountain pumped hydro achieves roughly 75% efficiency
“Of the energy that it takes to run all the pumps and stuff at Northfield Mountain, they get about 75% of it back.”
Kann: Lithium-ion storage cost scales directly with duration, penalizing long-duration use
“The problem with lithium ion is that The cost scales pretty directly with the duration. So if you want four hours of energy storage, it's great. But if you want 40 hours of energy storage, it's very expensive.”
Ackerman: Hydrostor's underground cavern pressurizes air to six atmospheres
“Water sitting up top, the air deep down below underground in the cavern, and that air is pressurized to six times the pressure of Earth's atmosphere at sea level.”
VanWalleghem: Hydrostor repurposes oil and gas machinery and workforce
“All of this equipment is from the oil and gas industry. So The compressors move natural gas down pipelines, the turbines are used in liquid natural gas processes, and the caverns are used to store typically natural gas. So we're keeping that workforce and thos…”
Kann: Compressed air energy storage has much better siteability than pumped hydro
“It has the promise of much better siteability than pumped hydro. There's actually lots and lots and lots of places we could do this and to Leah's point, it doesn't use as much above ground land”
Kann: Compressed air storage innovation centers on managing compression heat
“Historically, the challenge with compressed air energy storage has to do with this Trade off between efficiency and cost. So the basic challenge is when you compress air, you create heat, right? And if you let that heat dissipate into the atmosphere, you're ju…”
Ackerman: Molten salt storage delivers 80% to 90% round-trip efficiency
“And these molten salt tanks, they are quite efficient. You get back about 80 to 90% of the energy you put in.”
Kann: Energy Impact Partners invests in thermal storage company Rondo Energy
“We are not investors in pumped hydro storage in the moment. We are not investors in compressed air energy storage. We are investors in a company that does thermal storage, storage as heat, albeit not molten salt. So we're investors in a company called Rondo En…”
Kann: Storing electricity as industrial heat may be more valuable than grid storage
“So actually being able to store, you know, clean, cheap electricity as heat and then deliver it as heat may have as much, if not more value than turning that heat back into electricity to put it back on the grid. So specifically for the industrial heat applica…”
Kann: The US will not build much more pumped hydro storage
“Well much as I love pumped hydro storage I just realistically don't think we're gonna add a whole lot more of it, certainly here in the U.S., so I'm not gonna put any of my money into that solution, though it is probably the most mature and maybe the cheapest,…”