Xe-100
The Xe-100 is a Generation IV high-temperature gas reactor from X-energy. 0 units are operating and 0 are under construction, out of 16 on record.
Operating
0
—
Under construction
0
Planned
16
Cancelled
0
0 retired
A helium-cooled pebble bed reactor delivering 200 MW of heat at 750 °C, aimed at industrial process heat as much as electricity. Four units are planned with Dow at Seadrift, Texas. It runs on TRISO pebbles at HALEU enrichment, which is why X-energy is building its own fuel facility rather than buying on the market.
Design
| Vendor | X-energy |
|---|---|
| Reactor type | High-temperature gas reactor (HTGR) |
| Generation | IV |
| Capacity range | 80 MWe gross per module |
| Coolant | Helium |
| Typical enrichment | 8–20% U-235, frequently HALEU |
Where it is built
| United States | 16 units |
|---|
All Xe-100 units
| Unit | Country | Status | Gross MW | Online |
|---|---|---|---|---|
| Cascade SMR nuclear power plant 1 | United States | Pre-construction | 80 | 2032 |
| Cascade SMR nuclear power plant 10 | United States | Announced | 80 | 2035 |
| Cascade SMR nuclear power plant 11 | United States | Announced | 80 | 2035 |
| Cascade SMR nuclear power plant 12 | United States | Announced | 80 | 2035 |
| Cascade SMR nuclear power plant 2 | United States | Pre-construction | 80 | 2032 |
| Cascade SMR nuclear power plant 3 | United States | Pre-construction | 80 | 2032 |
| Cascade SMR nuclear power plant 4 | United States | Pre-construction | 80 | 2032 |
| Cascade SMR nuclear power plant 5 | United States | Announced | 80 | 2035 |
| Cascade SMR nuclear power plant 6 | United States | Announced | 80 | 2035 |
| Cascade SMR nuclear power plant 7 | United States | Announced | 80 | 2035 |
| Cascade SMR nuclear power plant 8 | United States | Announced | 80 | 2035 |
| Cascade SMR nuclear power plant 9 | United States | Announced | 80 | 2035 |
| Long Mott nuclear power plant 1 | United States | Pre-construction | 80 | 2033 |
| Long Mott nuclear power plant 2 | United States | Pre-construction | 80 | 2033 |
| Long Mott nuclear power plant 3 | United States | Pre-construction | 80 | 2033 |
| Long Mott nuclear power plant 4 | United States | Pre-construction | 80 | 2033 |
Sources
- Xe-100 — vendor documentation
- Global Nuclear Power Tracker, Global Energy Monitor, August 2026 release — CC BY 4.0 · retrieved 2026-09-06