Scientists propose a new centralized solar power generation method

2023-12-29

According to foreign media reports, Asegun Henry has a good idea to address climate change: to store solar energy. The professor of mechanical engineering at the Massachusetts Institute of Technology said, "Thisthe key, the key to leading many things in the right direction." Asegun Henry had a bold idea to save the world. He believes that the key to reducing carbon emissions and mitigating further climate change lies in the ability to achieve centralized solar power generation.

Today, most of the renewable energy obtained from the wind and sun is provided in the form of "use" or "loss". To store this energy, Henry envisioned a completely sustainable, zero carbon power grid that could meet all of our electricity needs, even on cloudy and windless days. And he has a blueprint for how to achieve this goal.

Imagine, in addition to solar power plants and wind turbines, there is also a heavily insulated, warehouse sized container filled with white hot liquid metal. Any excess energy captured during periods of low electricity consumption will be transferred to this container, where it will be converted into heat. When energy demand increases, liquid metal can be pumped into a converter to convert heat back into electricity.

Henry stated that this "sun in the box" system will serve as a rechargeable battery, even though it occupies half of the football field. He has proven that the key components of the system are effective and is integrating them to showcase a laboratory scale system. If this proves successful, he will advance a version that increases storage capacity and ultimately form a commercial scale power grid integration system.

Thisan ambitious path, and it is not without obstacles, just like Henry's own path into MIT. In 2020, he received a tenured teaching position in the Department of Mechanical Engineering at MIT and devoted most of his energy to researching centralized solar power generation methods.

"In my opinion, choosing to go to MIT is a path to saving humanity," Henry said. "I believe in this technology, believe it is the key, the key to guiding many things in the right direction."

Bold thinking

Henry was born in Sarasota, Florida and grew up in Tallahassee, where he became a drummer. His parents are both professors at Florida A&M University, and they make every effort to instill in him an appreciation for the West African roots of his family. When he was 10 years old, his mother took him to attend an African dance class at university. Henry said, "I have always been taught to respect African culture, but I have never truly seen or heard of it. That day, I completely fell in love with drums."

In the following six years, he joined a professional touring troupe and devoted himself to playing African drums. When he was 16 years old, he decided to give up his drumming career after seeing his teacher's financial difficulties. Around that time, he participated in a ceremony project for young black men, where he met his mentor Makola Abdullah, a professor of civil engineering at Florida A&M University. Abdullah hired Henry as his young assistant in the laboratory, and the team is studying the structure of the Egyptian pyramids.

Henry recalled, "This was really a turning point for me," he said. "I received my first payment for technical work, which was exciting at that age."

As an undergraduate student at Florida A&M University, Henry continues to work in Abdullah's laboratory, studying vibrations caused by earthquakes. He also developed an interest in atomic scale vibrations and atomic motion in thermal backgrounds, which led him to apply to graduate school at the Massachusetts Institute of Technology.

Henry's experience at MIT was academically tense, sometimes economically uncertain, and overall socially isolated. He said he was once a single black engineering graduate student in the department. He said, "This kind of (isolation) motivates me, and my task is to obtain my degree."

Henry continued to work hard, collaborating with his supervisor to develop molecular dynamics simulations of heat conduction, and obtained a master's and doctoral degree in mechanical engineering in 2009. Subsequently, he accepted a teaching position at Georgia Institute of Technology. He subsequently clarified his research objectives. At Oak Ridge, he learned to do electronic structure calculations. At Northwestern University, he entered the field of renewable energy and simulated promising solar thermal chemical materials. At ARPA-E, a department aimed at supporting high-risk, high return projects, he learned to think critically.

"I visited a mechanical workshop the size of Jurassic Park, where they manufacture the world's largest turbines and also visited a centralized solar power plant," Henry said. "That was a transformative experience, and I became interested in system level design."

"One step change"

He returned to Georgia Institute of Technology with an adventurous idea and proposed a new centralized solar power generation (CSP). Most CSP designs are based on the idea of storing heat as molten salt and converting liquid into electricity through metal pipes and pumps. But when storing heat, the temperature of salt is limited. Temperatures above this limit may also lead to rapid corrosion of metal pipes and pumps.

Henry said, "I'm interested in pushing this question to a higher dimension to see how to achieve a stepped change in performance." He suggested using more heat-resistant ceramics to make pipes and pumps, and not storing heat in molten salt, but in glowing white hot liquid metal.

Henry said, "Thisa radical idea, and based on physics, it is reasonable."

He and his students worked for many years to demonstrate a key component of the system, a high-temperature ceramic pump, which initially made little progress. In 2017, their efforts paid off with a pump capable of liquid circulation at temperatures as high as 1400 degrees Celsius. After this demonstration, they published an article in the journal Nature and achieved the Guinness World Record for the highest operating temperature liquid pump.

Henry said, "This escalates the situation," and he received an interview invitation for a teaching position at the Massachusetts Institute of Technology at the time. When he got this job, he was unsure if he could accept it. As his work moved forward, he was in the midst of a complex divorce.

He said, "I was at a difficult crossroads at the time. Should I stay and possibly get custody of my child, or should I work even harder and go to MIT, where I think I have a good opportunity to pursue this idea?"

Finally, Henry accepted the position and moved back to MIT in 2018. The divorce pushed him to the brink of bankruptcy, even though he was building a new laboratory and managing the teaching needs on campus. This was a tumultuous year, but he eventually moved to Boston with his sons, and just before the pandemic hit, Henry also secured a lifelong position.

"Thisa dramatic relief for me," Henry said. "After risking everything to come here, you hope to have this sense of security and things will be resolved."

He is working hard to improve the "sun in the box" system and will break his record with a higher temperature pump thereafter. He is still continuing to simulate the motion of atoms in different materials and converting these movements into sound - part of the inspiration for this project comes from his early musical experiences.

For the new balance he found in work and life, he said, "It's very reassuring. I'm very grateful."

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