Self-subsidizing Mercury Remediation with Fusion Reactors

TL;DR

Fusion reactors can permanently remove mercury from the environment by converting it into gold through neutron reactions, creating economic value and incentivizing pollution remediation.

Contribution

This paper introduces a novel method for mercury remediation using fusion reactors as neutron sources to transmute mercury into gold, combining environmental and economic benefits.

Findings

Mercury can be irreversibly converted into gold via fusion-induced nuclear reactions.

The global mercury stock is valued at approximately $200 trillion, surpassing gold reserves.

Co-producing gold with electricity in fusion plants can triple their revenue.

Abstract

Fusion reactors can permanently remediate mercury by using it as a neutron multiplier: each (n,2n) reaction reduces the neutron number towards ${}^{197}$Hg which quickly decays into stable gold, irreversibly removing it from the environment while generating substantial economic value. Fusion energy is therefore not merely environmentally benign, but anti-polluting through the continuous consumption of an environmental pollutant. The history of nuclear fission demonstrates that environmental concerns can be decisive obstacles to low-carbon power deployment, suggesting that integrated pollution remediation fundamentally improves the policy calculus for fusion energy. We show that at high neutron flux (achievable in muon-catalyzed and inertial confinement fusion), nuclear reactions make all mercury isotopes eligible for gold transmutation, incentivizing mercury recovery and valuing the world mercury extractable stock at ${\sim}\$200$ trillion, exceeding all in-ground gold reserves. Co-producing gold alongside electricity can triple a fusion plant's revenue, aligning economic incentives with complete, permanent mercury remediation.