This document discusses an HVAC assessment for rooms in the ITER Organization concerning the ICL. It was found that two rooms, 14-B2-20 and 14-L1-21, may exceed 25C. The results were calculated based on air handling unit specifications and thermal equilibrium assumptions. Additional analysis estimated required AC power at different temperature differences and insulation levels, noting that the analysis for rooms in B14 can assume 60-65% of estimates for typical domestic buildings due to increased wall thickness. There is uncertainty in the estimates as a simple calculation method was used and interior rooms have less heat exchange with the exterior.

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HVAC Assessment

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results
• Results for the room concerning the ICL, just two
rooms may run above 25C:
– 14-B2-20
– 14-L1-21
Room
excess cooling
power (HVAC
+ LAC - heat
loads) at 35C
(kW)
excess
cooling
power (HVAC
+ LAC - heat
loads) at 25C
(kW)
14-B1-23 15.8 9.3
14-B1-22A 11.1 8.5
14-B1-22 26.6 22.9
14-B1-24 14.2 7.4
14-B2-20 9.9 -3.6
14-B2-21 13.6 11.4
14-L1-22 38.8 23.3
14-L1-21 -0.7 -4.2

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How I got the results
• Calculated how many kW the HVAC can remove based
on Air Handling Unit (AHU) specs and the following
assumption, :
– Air supply temp (C) to HVAC: 18C (as per spec)
– Humidity: 8.2 g water/kg dry air (as per spec)
– 1-Assumed outlet temperature of HVAC air toward exhaust
fan:35C thermal equilibrium with the room at 35C
– 2-Assumed outlet temperature of HVAC air toward exhaust
fan:25C thermal equilibrium with the room at 25C
– Calculated the delta enthalpy between inlet and outlet of each
room assuming constant humidity, using HVAC air flow from
P&IDs
– Results in last column of the table

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How I got the results
• Using several online tools for domestic application, I
have estimated which would be the required A/C power
to keep a certain temperature difference VS
environment with three different level of insulation:
– Temperature difference VS external environment of:
• 5C
• 10C
• 15C
– Insulation level:
• Good
• Normal
• Poor
• Results in the table

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How I got the results
• Assessed what normal, good and poor insulation mean
and how they compare with the rooms in the tritium
building:
– Domestic (0.25m wall thickness)
• 5C of delta T (assuming 40C outside and 35C inside the room)
– Good insulation: 0.15 W/(m*K) 300W every 100m2 of
exchange surface
– Normal insulation: 1 W/(m*K) 2000W every 100m2 of
exchange surface
– B14 (0.7m wall thickness)
• 5C of delta T (assuming 40C outside and 35C inside the room)
– Solid concrete: 1.8 W/(m*K) 1286W every 100m2
– Solid concrete: 1 W/(m*K)714 W every 100m2

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How I got the results
• Based on the thermal conductivity numbers and the
different wall thicknesses between a typical domestic
situation and the rooms in B14, we can assume that:
– We can consider around 60-65% of the estimated A/C
consumption by the online tools for the situation in B14 (e.g.):
• For domestic application, the expected cooling power required is
2.6kW to keep a 5C difference with the external environment
(assuming 40C outside 35C inside)
• We can consider around 65% of 2.6kW for a room inside
B141.7 kW

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Uncertainty
• The required cooling power, for each B14 interior room,
is over estimated since they do not share walls with the
exterior.
• This way of estimate heat load is pretty simple so has a
significant level of uncertainty