30
NuclearPlantJournal.com Nuclear Plant Journal, May-June 2014
12.
How often the plant refueling will be
needed?
½ of the core every 18 months.
13
You may share any domestic or
international utilities who have expressed
interest in NGNP’s HTGR?
The design will deployed for
industrial process heat usage. The plant
will be operated by a nuclear process heat
utility operator. Several utility operators
are interested since many have existing
customers in industrial settings that are
interested in least cost energy options.
The Alliance is focused on industrial
end-users and not just utilities. Entergy
Corporation, a utility headquartered in
New Orleans, Louisiana has been an
active member of the Alliance and has
participated in studies supporting viability
of deployment projects for industry.
Over the past five years, the Alliance
has met with most U.S. Nuclear utilities
who are tracking the development of the
technology and have interested industrial
users as customers.
Internationally, the Alliance is
collaborating with Korean Nuclear
Hydrogen Alliance (see
.
korea.com/archives/49866
).
It
has
endorsed work on the High Temperature
Test Reactor (a prismatic block HTGR)
in Japan for the Japan Atomic Energy
Agency (JAEA), and is working with the
Nuclear Cogeneration Industrial Initiative
(NC2I) European Alliance (see http://
) to forman agreement that
is mutually beneficial to our mission of
commercializing HTGR technology.
14.
How have the lessons learnt from
Fort St. Vrain nuclear power plant been
incorporated to ensure the technological
success of NGNP’s Small Modular
Reactor?
While Fort St. Vrain (FSV)
experienced a number of issues consistent
with its status as a demonstration plant,
the most impactful issue was water
ingress through the novel, aggressively
designed water- lubricated bearings for
the circulator which required maintaining
a delicate pressure balance between the
lubrication system and the primary circuit
helium.
While none of the issues posed a
safety concern, the water ingress was
a major operational problem, resulting
in long outages to remove the water. In
contrast the preceding Peach Bottom I
HTGR used more conventional, electri-
cally driven circulators with oil-lubricat-
ed bearings and did not experience water
ingress problems.
The SC-HTGR uses electrically
driven circulators supported on magnetic
bearings eliminating the main source
of water ingress at FSV. In addition,
provisions are made to drain liquid water
from the primary vessels in the unlikely
event if it enters from another source.
A direct result of the water in FSV
was corrosion and adverse interaction
with internal lubricants such as in the
control rod drives. Such locations offer
a cold trap where water can collect. In
the SC-HTGR design, such sensitive
locations are purged with clean dry
helium to prevent the buildup of moisture
or other potential contaminants.
Another lesson related to FSV
concerns with the fuel cycle. FSV
used a thorium/HEU fuel cycle. While
neurotically optimum, the highly
enriched uranium (HEU) cycle is costly
due to security concerns associated with
the manufacturing and transportation of
fuel. The SC-HTGR uses a low enriched
uranium (LEU) cycle, eliminating the
HEU issues.
All of the FSV “lessons-learned”
are being addressed in the SC-HTGR
detailed design. But the points discussed
above were the most important.
15.
Provide a brief description of the
NGNP’s HTGR by providing additional
information which is not covered above.
Today, process heat requirements
for energy-intensive industries around
the globe are provided almost entirely
by fossil fuels. Electrical power for
these industries is provided primarily
by combusting solid, liquid and gaseous
fossil fuels. Consequently, these
industries are hostage to environmental
concerns, unpredictable government
policies, uncertainty of supply and
price volatility. Modular HTGR nuclear
technology provides an important option
that addresses these issues. It provides
process heat at the temperatures needed
by industry and power with competitive
economics, compelling safety, and
minimal environmental concerns.
For markets reliant on premium
fossil fuels, commercializing the HTGR
makes available the only game-changing
technology on the horizon that can address
global energy policy goals of energy and
feedstock security, economic growth
(jobs) and carbon footprint. Trends in
fossil fuel prices suggest that modular
HTGR technology integrated with carbon
conversion technologies provides an
economic approach to production of
synthetic transportation fuels, chemical
feedstocks and chemicals with a minimal
carbon footprint.
During both normal operation and
under accident conditions no explosive
gases are produced by the fuel materials or
core infrastructure — the materials were
selected and designed to preclude this.
Used nuclear fuel from a HTGR requires
no cooling water or active systems for
storage or heat transfer, relying instead
on natural convective air flow.
The safety case has been
demonstrated
in
the
German
Arbeitsgemeinschaft
Versuchsreaktor
(AVR) HTGR and recently in the 10
and 30 MW designs in China and Japan
respectively. In those tests, self-limiting
reactor shutdown was demonstrated by
stopping normal operation forced cooling
of the helium. The reactor heated up to
a safe temperature where the nuclear
fission reaction intrinsically shut itself
down without any damage to the reactor
and without any release from the ceramic
coated fuel.
Nearby public and industries need
not shelter or evacuate for any event
challenging reactor safety. This allows
a close-in siting capability needed for
process steam/heat loads, plus anticipated
improved public and investor acceptance.
Long-term investment risk due to safety
concerns is minimized for both the
reactor plant itself and for collocated
industrial facilities.
Contact: Dr. Finis Southworth,
Ph.D., NGNP Industry Alliance Limited,
P.O. Box 837, Ridgeland, Mississippi
39158-0837; telephone: (601) 591-5431,
fax: (601) 591-5431, email: secretary@
ngnpalliance.org.
HTGR Reactor...
