Fusion and the Carbon Question

Fusion produces no carbon dioxide at the point of generation; the honest accounting extends to construction and fuel-cycle emissions.

No combustion, no generation-point CO2

A fusion reaction fuses light nuclei; it does not burn carbon. There is no carbon dioxide, no methane, and no particulate exhaust from the reaction itself. That is a structural property of the physics, true for both the breeder (Hyperion) D-T reaction and the burner (Aegis / MetroVolt) D-3He reaction.

But lifecycle carbon is not zero

Honest carbon accounting looks beyond the point of generation. Building a plant uses steel, concrete, superconductors, and specialized materials, all of which carry embodied emissions from today's industrial supply chains. Operating and eventually decommissioning a plant also has a footprint. A credible clean-energy claim must include these, not hide behind the clean reaction.

• Generation-point CO2: none, for both machines
• Embodied CO2: real, from construction and materials — shared with all large infrastructure
• Fuel-cycle CO2: small, tied to processing and enrichment energy sources

We treat these on lifecycle thinking and honest environmental accounting. As the grid that supplies construction energy itself decarbonizes, embodied emissions of new clean plants fall — a virtuous coupling, but not something to claim as already achieved.

We make no operating-emissions comparison from real plant data, because neither machine is built. The claim we stand behind is narrow and physical: the reaction emits no carbon dioxide.