Page 99 - Applied Photovoltaics

x laminated module
x photovoltaic roof tiles
x laminates for building integration.
Fig. 5.19 shows the temperature rise above ambient for a selection of module types.
Module temperature rise above ambient is approximately linear with increasing
insolation level.

Figure 5.19. Temperature increases, above ambient levels, with increasing solar
irradiance for different module types (Ross & Smokler, 1986).

The nominal operating cell temperature (NOCT) is defined as the temperature
reached by open-circuited cells in a module under the following representative
conditions:
irradiance on cell surface = 800 W/m 2
air temperature = 20°C
wind velocity = 1 m/s
mounting = open rear surface.
In Fig. 5.19, the best module operated at an NOCT of 33°C, the worst at 58°C and the
typical module at 48°C. An approximate expression for calculating the cell
temperature is given by (Ross & Smokler, 1986)

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