Fire Hazard and Risk Assessment Battery Energy Storage System (BESS)

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The fire growth and spread were modelled using the National Institute of Standards and Technology (NIST) Fire Dynamics Simulator (FDS) software package and Smokeview which is used to view the results.
Fire Dynamics Simulator (FDS) is a computational fluid dynamics (CFD) model of fire-driven fluid flow. The software solves numerically a form of the Navier-Stokes equations appropriate for low-speed, thermally-driven flow with an emphasis on smoke and heat transport from fires.
6.2.1 220KV HV Substation.
In accordance with the methodology described above and considering the characteristics of the transformer of the substation, a bund of approximately 157m2 with a fire of 197.4 MW (Figure 23) is estimated.
Volume oil
60000.00
L
60.00
m3
Bund
Area TK & Radiator
23.00
Ideal mass loss
0.039
kg/sm2
kb
0.70
m-1
Xᶍ
0.70
Combustion efficiency
A
157.00
m2
V Bund
52.33
m3
D
14.14
m
m"
0.039
kg/m2.s
Hc
4.605E+07
J/kg
q
1257.10
kW/m2
Ballast Factor
1.00
-
Without ballast = 1, with ballast = 0.2.
Q
197.36
MW
Figure 23: HRR Calculation substation
The FDS model boundary conditions are presented in Figure 24, and the fire scenario characteristics are as follows:
◼ FireOrigin:Transformeratsubstation220KVHV.
◼ Firegrowth:Instant.
◼ Weather conditions (refer to Section 4.1.2): Wind speed – 3.24m/s; temperature – 17oC; Relative humidity – 74%.
◼ Heatreleaserate:197.4MW(Figure23above).
◼ Hydrocarbon (transformer fires, properties obtained from Table 3-4.19 of SFPE handbook):
◼ REAC ID=”REAC”
C=4.00 N=0.00
H=10.00 HEAT_OF_COMBUSTION=4.605 x107 O=0.00 SOOT_YIELD=0.0600 gr/gr
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FHRA 11 21 December 2023