Chernobyl Nuclear Accident Congressional Hearings Transcript

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Question 1
From what I understand, a Modular High Temperature Gas Reactor
(MHTGR) contains neither zirconium fuel cladding nor water -- two
of the major "players" that resulted in the formation of hydrogen
and the subsequent hydrogen explosion that caused the sudden,
massive release of radioactivity into the atmosphere at Chernobyl.
So this kind of accident scenario is virtually impossible for an
MHTGR. Am I correct?
Answer
Your understanding is correct. The Modular High Temperature Gas-
Cooled Reactor (MHTGR) uses inert helium gas as a coolant so that
no reaction or explosion can take place between the coolant and
the fuel, fuel coating, or structural materials in the reactor
system. Further, no zirconium is present in the system so that
even in the rare circumstance where water would enter, no
metal/water reaction would take place to result in the formation
of hydrogen with a subsequent explosion. Although water may,
under certain circumstances, react with the graphite in the core,
the reaction is endothermic (absorbs heat) and therefore selflimiting
so that the Chernobyl type scenario is virtually
impossible.
Question 2
Is there interest on the part of the utilities in buying an MHTGR,
if they prove to perform as promised?
Answer
Historically, the electric utilities have supported the HTGR
program since 1978 through Gas-Cooled Reactor Associates (GCRA), a
utility user supported and managed organization. This group
represents about a third of the nation's generating capacity. The
specific design features of the MHTGR have been determined to meet
performance, safety, and investment requirements established
specifically by the GCRA utilities. Further, these utilities are
currently leading development of a Project Plan, which calls for a
significant investment from the private sector - primarily the
utilities themselves, that would lead to the demonstration of the
MHTGR concept and to its licensing certification for replication.
These activities are based on the conviction that the concept when
demonstrated will provide an advanced, second-generation nuclear
plant for installation by utilities domestically, as well as
outside of the United States.
Question 3.
Are DOE and EPRI participating with you and others in the
development and prototype testing of the MHTGR reactor design?
Please elaborate. What kind of funding would it take to fully
design, build and test an MHTGR?