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Reference data
Page built2026-10-22
Data as ofAugust 2026

THTR-300 nuclear power plant

Retired Germany
Gross capacity
308MW

THTR-300 nuclear power plant is a high-temperature gas reactor unit at THTR-300 nuclear power plant in Germany rated at 308 MW gross. It is retired. Commercial operation began 1 Jun 1987.

Specification
Reactor type High-temperature gas reactor (HTGR)
ModelPebble bed reactor
SizeLargeabove 300 MWe
CoolantHelium
ModeratorGraphite
Gross capacity308MW
Net capacity (reference)296MW
Net capacity (design)296MW
Thermal output760MWt
NSSS vendornot on record
Typical enrichment8–20% U-235, frequently HALEU
Ownership & location
SiteTHTR-300 nuclear power plant
Unitnot stated
CountryGermany
OwnerHochtemperatur-Kernkraftwerk GmbH100%
OperatorHochtemperatur-Kernkraftwerk
Coordinates 51.6803, 7.9720
Fuel chain for this unit
Fuel form
TRISO-coated particle fuel in pebbles or compacts
Enrichment
8–20% U-235, frequently HALEU HALEU dependency
Who makes this assembly
Upstream

Enriched fuel means this unit sits downstream of five conversion plants and four enrichment operators holding 88% of world capacity between the top three.

RosatomUrencoCNNCOrano

This design needs HALEU, enrichment above 5%. Western production is currently measured in hundreds of kilograms a year.

Conversion
AEOICamecoCNNCCNNCCNNCConverDynOranoRosatomTVELWestinghouse
Fabricator capability is recorded against reactor type and model line, not against named units, utilities do not publish fuel contracts. See the fuel chain.

Timeline

  1. 3 May 1971Construction start
  2. 13 Sep 1983First criticality
  3. 16 Nov 1985Grid connection
  4. 1 Jun 1987Commercial operation
  5. 29 Sep 1988Permanent shutdown

Sources

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