What Firm Power Means

Firm power is capacity you can count on in a specific hour, independent of weather or time of day — the property data centers value most.

Firm vs available vs intermittent

Grid planners separate three ideas that casual use blurs. Nameplate capacity is what a plant can produce at its best. Available capacity is what it can produce right now, after outages and maintenance. Firm capacity is what you can promise for a given hour with high confidence, months ahead. A solar array has large nameplate and near-zero firm capacity at midnight; a well-run thermal or fusion plant aims for firm capacity close to its nameplate.

The burner is engineered toward high firm capacity because its output does not depend on sun, wind, or season. A tandem-mirror plasma either burns or it does not; when it burns, its power is steady. That makes the quality of the megawatt-hour attractive to compute operators, who care less about a low average and more about the guarantee for the next hour.

But firmness is a probability, not a promise carved in stone. It is set by how often the plant is down and for how long — its availability. As a design-and-simulation study, the burner's modelled availability is 0.86 to 0.995. Firm capacity you would actually contract sits below the availability figure, and that is why the data-center architecture pairs the burner with redundant sources.

• Nameplate ignores outages; firmness accounts for them
• Fusion output is weather- and season-independent by construction
• Firm capacity <= availability, always
• Contracted firmness for compute must be built from a hybrid, not a single unit today