From Classroom to Hard Tech

When Allie Wiegel YSE ‘25 walked into Steph Speirs's "Climate Tech Innovation and Commercialization" class during her final semester, she thought she wanted a career in climate finance. By the end of the course, she had found something entirely different, and far more aligned with her passions.

Today, Wiegel serves as Chief of Staff at Nth Cycle, a company revolutionizing critical mineral refining. Her journey from student to startup leader illustrates the transformative power of hands-on learning and the right mentorship at the right moment.

Wiegel came to Yale with extensive experience in corporate sustainability, having worked at Comcast, Google, and consulting at Antea Group focusing on carbon accounting and low carbon transition planning. After almost a decade, she wanted to more directly drive decarbonization in industry. Graduate school offered her the chance to explore where she wanted to make an impact.

"I thought I wanted to do clean energy finance when I went to grad school," Wiegel explains. “It felt like the straightest path to the greatest impact.” Through Speirs's class, she discovered her true calling: "I realized I loved the gnarly, thorny, ugly, not-sexy problems, specifically industrial decarbonization like green cement, green steel, and critical mineral refining.”

The course featured guest speakers from cutting-edge climate tech companies, each presenting real-world challenges and engaging students in rigorous problem-solving discussions. When Nth Cycle's CEO Megan O’Connor spoke to the class, Wiegel was captivated. “Megan is a scientist and could have easily gone deep into the technical details, but instead she explained Nth Cycle’s complex electrochemical process in a way everyone could understand,” Wiegel recalled. In O’Connor, she saw what true, scalable decarbonization looks like. Drawing on her own professional experience, Wiegel was excited by Nth Cycle’s approach: “We’re building a commercial refining system that tackles the biggest challenges of traditional refining — we’re modular, scalable, and cost-effective, with a fraction of the environmental impact. These are the kinds of solutions that will have the greatest impact.”

What made Speirs's class particularly valuable was its deliberate mix of students from both the School of Management and the School of the Environment. "Environmental professionals are crucial in climate tech," Wiegel notes. "There were times when an SOM student would ask a question and a YSE student would be able to respond with insight, advice, or an explanation for why something would or wouldn’t work. The same was true in reverse. It takes both sides to bring these solutions to market.”

This interdisciplinary dynamic proved essential preparation for her current role, where she works daily with both seasoned engineers and commercial professionals. "If you're going to work in this industry and you want to build a technology that makes a difference, you have to be in this class," she says.

Speirs's impact extended beyond lectures. Her office hours became a crucial resource as Wiegel navigated her career transition. When Nth Cycle invited Wiegel to visit their offices, Speirs helped her prepare.

That preparation paid off. When Nth Cycle did offer a chief of staff position, Wiegel felt confident enough to be candid about what she needed to succeed in the role—a conversation that ultimately shaped how she and O’Connor work together today.

"Steph Speirs and her class are the reason I have this job from start to finish," Wiegel says. “If you’re considering a career working on these challenges, this class will give you insight and perspective from people building these companies today. Show up, do the work, and respect the opportunity to learn from serious entrepreneurs tackling critical challenges.”