Solar energy system design: The impact of mesoscale variations in solar radiation

A 12‐station network located in and around Vancouver, B.C. has been used to define the local (mesoscale) variations in solar energy. Numerical models are used to convert the horizontal data to inclined surface irradiances which, along with temperature, are the inputs required by the simulation models used to assess the significance of these variations on the performance and economics of both active and passive solar heating systems. Solar radiation differences over the study area have a marked influence on the operation of a domestic hot water heating system while the temperature variations between the same stations have a comparatively small impact. For both active and passive space heating the situation is reversed because temperature has a large impact on the energy demand and hence on the extent of solar energy utilization. The results suggest that local variations of solar radiation should be incorporated in solar domestic hot water design studies while spatial variations in temperature should receive relatively more attention in space heating studies.