Baseload Solar Power for California? Ammonia-based Solar Energy Storage Using Trough Concentrators – A Study of Heat Losses

Heat losses from a trough cavity receiver were investigated in order to eventually optimise the reactor geometry for ammonia-based solar energy storage with troughs, which are prominent in the SEGs plants of California. To this end, experiments were performed with a small-scale receiver containing heating elements. This gave free convection loss coefficient values from 0.3 to 11.8 W/(m.C) from 90 degrees inclination to zero degrees inclination respectively. This accounted for 2 to 40% of the total heat losses in each case. An attempt to apply the free convection correlation developed by Paitoonsurikarn (2006) showed that in its current form, the correlation does not accurately predict these free convection losses. Application of the heat loss model to actual solar dissociation results showed that an iterative heat loss calculation is necessary to accurately represent the heat loss at the reactor, and that further investigation of forced convection losses is necessary.