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MacroCycle Technologies




Cambridge, MA



Stwart Peña Feliz

Co-Founder & CEO, MacroCycle Technologies

Stwart Peña Feliz joins Breakthrough Energy’s Innovator Fellows program from MacroCycle Technologies in Cambridge, Massachusetts. With a background in process engineering and business development, he brings energy and enthusiasm to overcome the challenges of commercializing hard tech to create a positive environmental impact. As the co-founder and chief executive officer of MacroCycle, Stwart leads the commercialization of the technology and fundraising and operations of the venture.

MacroCycle Technologies’ patented technology converts plastic waste into virgin-grade quality recycled plastic through a process that requires 80% less energy than competing depolymerization processes and can be powered with renewable energy to be entirely carbon free. Through the Fellows program, MacroCycle will optimize the technology for various waste streams and scale up to provide customers sufficient material to make the first zero-carbon upcycled PET bottles.

Stwart studied at Cornell University, where he earned his Bachelor of Science in chemical engineering. After multiple years in industry, he earned his Master of Business Administration from the Massachusetts Institute of Technology Sloan School of Management. Stwart’s goals are deeply rooted in climate tech, and he plans to use his experience and resources to one day democratize access to clean energy for individuals all over the world, especially those in his home country of the Dominican Republic.


What is your favorite word and why?
Hope. Because a person can survive 30 days without food, four days without water, eight minutes without oxygen, but not a single second without hope.

What beliefs drive you?
A life lesson my mom imparted to me that has allowed me to live my best life: as long as your happiness depends on something, it means it can be taken away. Therefore, be happy for no reason.

Share a fun fact about yourself:
I have successfully jumped out of planes more than 200 times all over the world!