Fast Pitches: Generation/Distribution: ARPA-E Experts Discuss the Most Exciting Energy Opportunities of the Decade

DENVER — At the ARPA-E Energy Innovation Summit 2022, panel participants in “Fast Pitches: Generation/Distribution,” shared their thoughts on all phases of energy generation and power distribution: above ground, below ground, reuse the ground, and even up to the stars. Panelists included Dr. Scott Hsu, ARPA-E Program Director for Fusion Programs; Dr. Philseok (Phil) Kim, ARPA-E Program Director; Dr. Douglas Wicks, ARPA-E Program Director; Dr. Emily Yedinak, ARPA-E Fellow; and Dr. Jennifer Shafer, ARPA-E Program Director.  

Making underground power cost-effective and resilient

Kim started off with insights on undergrounding power lines to make neighborhoods cleaner and more attractive, and power outages are less frequent. He outlined new technologies that make undergrounding power lines affordable and reliable. A common misconception is that burying power lines is too disruptive and expensive, and that problems are more difficult to diagnose once lines are buried. The opposite is true, based on data from European countries that have underground power.

The U.S. lags, but ARPA-E is rethinking how lines can be buried at reduced costs and improved performance. For example, technologies already in use in the oil and gas industry have to potential to enable underground construction without surface disruption by drilling through various geologic conditions with precision, steerability, and high rates of penetration; creating conduits in situ; and constructing vaults while drilling to minimize vault sizes and numbers. There are still issues to overcome such as obstacle avoidance, installation and splicing errors, and failure detection, but the potential for more resilient, cost-effective underground power is real and progressing.

Harnessing geologic hydrogen to scale the hydrogen economy

Yedinak discussed the importance of white (geologic) hydrogen in the future hydrogen economy build-out. “The earth is a giant planetary geo-reactor,” she said, “with trillions of chemical reactions occurring on a constant basis, fueling the biological processes that underscore life as we know it, shaping mountains and continents, and doing for free what we are spending billions to replicate — all without any intervention on our part.” She noted that chemical reactions all day, every day convert carbon dioxide into sugars and underpin the global carbon cycle. She explained two of the most important reactions that occur when water reacts with rock:  radiolysis and serpentinization. She proposes that this geologic, or white hydrogen, a byproduct of earth’s georeactor, has important implications for the hydrogen economy.

Hydrogen is crucial because it is a critical chemical feedstock and a zero-carbon energy carrier for a decarbonized economy. Today, it is primarily used in chemical refining and ammonia production, but in the future could have an important role in several industries including synthetic fuel production, transportation, metals refining, home heating, power generation, and as a grid balancer. Hydrogen is a particularly attractive option in industries that are difficult to decarbonize.

The way hydrogen is produced today, however, is anything but clean. What will be required is an industry overhaul on a massive scale. The use of carbon capture and renewable energy will not be enough to scale the industry without major negative climate effects — but naturally occurring or artificially stimulated hydrogen accumulations, she believes, could serve an enabling role in successfully scaling the hydrogen economy.

Using alchemy to transform stone into hydrogen

Wicks focused on gold hydrogen and the question, “Can georeactors replace alchemy to transform stone into gold hydrogen?” Iron (II) silicate, a naturally occurring rock, is nature’s source of hydrogen, produced by a rock-to-rock reaction involving water that produces hydrogen as a byproduct. Iron (II) silicates can be found in olivine-type (volcanic) rocks, Forty percent of the earth's crust is olivine-type rocks and 10 percent of that is applicable iron minerals. After a back-of-the-envelope calculation, Wicks estimated that it may be possible to produce 2.6 x 1015 tons of potential hydrogen, enough to meet millions of years of hydrogen demand.

Challenges remain. The rock must be reached in situ. The reaction is thought to be slow, very deep underground, and no chemist has tried to accelerate it. It also happens under extreme conditions. Also, there are a lot of things underground that need hydrogen. It’s a fuel source for bacteria, for example. To realize the vision, we’ll need to find and reach deep earth deposits, catalyze the mineral reaction, and eliminate parasitic hydrogen reactions. But if all this could be accomplished, we would be able to harness a near-inexhaustible source of clean hydrogen. 

Repurposing nuclear waste to power advanced reactors

Shafer’s presentation discussed how to take things that are already out of the ground and use them more effectively. Nuclear energy, she said, is going to play an increasingly important role in our clean energy transition, but there are open questions regarding how we handle and manage waste. An obvious option is to recycle waste material and put it back into advanced reactors to limit the actual amount of waste that is produced. Today, only about five percent of energy is consumed in the fission process in the current light water reactor fleet; 95 percent of the fuel left behind can be repurposed to produce clean energy. “The elements left behind don’t represent waste,” she said, “but instead present an opportunity that’s sitting there for the taking.” 

The unused fuel could be used for nuclear medicine, nuclear batteries, and non-radioactive needs. The intrinsic value just for UNF and transition metals is on the order of $60 billion, even not accounting for fuel. In terms of raw materials extraction, “We have enough material actually on our earth’s surface right now in the U.S. that we could be powering our advanced reactor fleet with materials that currently sit already mined and available for use,” she said, “bringing U.S. nuclear energy into a post-resource world.”

Several challenges remain, including costs and safeguards. This is why ARPA-E has launched the C.U.R.I.E. program to convert UNF radioisotopes into energy and determine ways to build reprocessing facilities and improve material accountancy, observation, and operational costs. The vision is to take the 90,000 metric tons of material and use it to fuel our clean energy future. 

Fusion energy: a bright decade ahead

Hsu closed the session by outlining fusion’s bold decade ahead. He clarified that he has recently taken a role as DOE’s Lead Fusion Coordinator, where he is spearheading public-private partnerships to fuel momentum for commercialization of fusion. 

This March, a White House fusion summit was held signaling ambition to partner with the private sector to realize at least one commercially relevant fusion pilot plant on a decadal time scale. Participants in the event celebrated decades of progress and major technical achievements in fusion thanks to sustained bipartisan support. They also recognized that fusion has a unique opportunity to differentiate itself as a clean energy technology not only in the way it uses physics but also, Hsu said, in the way that “we can engage society starting immediately to support energy justice and build a diverse workforce that looks like and benefits all of America.” 

Several attendees from the ambitious fusion private sector detailed their plans to develop and deliver fusion as a globally scalable, carbon-free energy source on a time scale that matters. ARPA-E’s fusion programs now span 40-plus projects, four programs, and an exploratory topic — all changing what's possible in innovative fusion concepts. “ARPA-E’s fusion programs along with the fusion private sector brought a new perspective and urgency to take higher technical risk and to focus the R&D on developing fusion systems that will find customers and markets. We also proved that targeted public investments in fusion could lead to significantly greater private investments,” he said. “To date, about a hundred million dollars of ARPA-E fusion investments have led to over 600 million dollars of private investments.”

The bold decadal vision seeks to work closely with the private sector to solve the remaining significant R&D challenges to realize at least one commercially relevant fusion pilot plant. The goal is to begin commercial deployment in the 2030s and enable aggressive commercial deployment in the 2040s. “This is very ambitious, and it will be hard,” he said, “but this is worth doing because game-changing innovations like fusion are the best chance for the world to reach global net zero while ensuring the U.S. can maintain its energy security and its technological leadership in the 21st century and beyond.”