  We present a model of the stellar populations in the fields observed by one
of the SuperWASP-N cameras in the 2004 observing season. We use the Besancon
Galactic model to define the range of stellar types and metallicities present,
and populate these objects with transiting extra-solar planets using the
metallicity relation of Fischer & Valenti (2005).
  We investigate the ability of SuperWASP to detect these planets in the
presence of realistic levels of correlated systematic noise (`red noise'). We
find that the number of planets that transit with a signal-to-noise ratio of 10
or more increases linearly with the number of nights of observations. Based on
a simulation of detection rates across 20 fields observed by one camera, we
predict that a total of 18.6 \pm 8.0 planets should be detectable from the
SuperWASP-N 2004 data alone. The best way to limit the impact of co-variant
noise and increase the number of detectable planets is to boost the
signal-to-noise ratio, by increasing the number of observed transits for each
candidate transiting planet. This requires the observing baseline to be
increased, by spending a second observing season monitoring the same fields.
