Economical Proton-Boron11 Fusion

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OPEN 2021
Princeton, New Jersey
Project Term:
03/17/2022 - 03/16/2025

Critical Need:

Proton-boron11 (pB11) fusion is attractive because protons and boron-11 are readily available and non-radioactive. The fusion of proton and boron produces only helium and no neutrons that activate surrounding structural materials. This absence of radioactivity lessens engineering and waste-disposition challenges. Yet economical pB11 fusion remains physically challenging because pB11 fusion requires temperatures so high that losses due to radiation overshadow energy production. The problem to be solved is to minimize these losses so that the pB11 fusion reaction can be used to deliver economical fusion power.

Project Innovation + Advantages:

Princeton University aims to find fusion configurations that could minimize radiation losses while maximizing fusion reactivity. In a vigorously rotating pB11 plasma, the heavier boron ions will be centrifugally confined far from the lighter protons. Then means are provided such that the very energetic protons, which are responsible for fusion, preferentially come into contact with the boron. Because the likelihood of a collision resulting in fusion essentially only depends on the proton energy, the boron ions and the electrons can be kept relatively cold, mitigating the radiative losses and perhaps enabling a pathway to economical pB11 fusion.

Potential Impact:

This project presents a radically new approach to enable the ideal form of fusion energy with truly abundant fuel and no radioactivity.


Both protons and boron-11 are abundant and non-radioactive.


Harnessing fusion energy would be immensely important in reducing U.S. and global reliance on fossil fuels that create harmful greenhouse gas emissions.


Both protons and boron-11 are readily available naturally and cheaply.


ARPA-E Program Director:
Dr. Robert Ledoux
Project Contact:
Prof. Nathaniel Fisch
Press and General Inquiries Email:
Project Contact Email:

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