Research Needs for Magnetic Fusion Energy Sciences - US Burning ...

• techniques and instruments to accurately measure and reduce impurities that deter
clearance of in-vessel components.
• advanced radiation-resistant remote handling equipment capable of handling sizable
components with high doses > 10,000 sv/h.
• 3-d codes that map the activation source term around the torus.
• efficient detritiation system capable of removing and handling the majority of tritium
from activated materials.
• Fusion-specific clearance limits issued by legal authorities; and recycling and clearance
infrastructure and market.
integration of the materials life cycle management strategy into overall fusion development pathways
will identify additional research needs.
REliaBility, availaBility, MaiNtaiNaBility, aNd iNSpEctaBility (RaMi)
introduction
to successfully harness fusion energy, one must have a product that will operate reliably, with acceptable
brief downtimes for maintenance. demo is the device on which the performance expectations
for future fusion reactors will be based, including its reliability and maintenance characteristics.
demo must demonstrate a high enough availability for power producers to commit to
building a commercial fusion plant. it is not reasonable for power producers to expect an ultimate
fusion power plant availability of 80% or more if demo cannot demonstrate an availability of
50% or greater. The Priorities Panel recognized the importance of achieving high availability on
demo with the statement that it must:
Demonstrate the productive capacity of fusion power and validate economic assumptions about
plant operations by rivaling other electrical energy production technologies.
achieving 50% availability on demo would be a huge accomplishment. The fission area started
with numerous nuclear facilities and the early reactors typically had an availability of 60% or less.
it took a number of decades and iterations in design for the technologies and operating procedures
to mature and allow the achievement of the 90% availability found in the Us today.
in the fusion case, the development path runs from iteR to demo, and demo is more demanding
than iteR in a number of regards, notably:
• The availability must increase by 5 to 10 times.
• The heat and neutron fluxes are doubled.
• The neutron fluence will be more than an order of magnitude greater.
in addition, fusion plants will be more complex than fission plants, requiring many complex systems
with remote handling: for example, blankets, divertors, plasma heating and current drive
systems, and plasma diagnostics. as was the case in fission development, fusion will require a
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