Energy/economic models must predict the mix of energy technologies in
competitive energy markets. We examine a market composed of several co
mpeting technologies with geographically heterogeneous cost distributi
ons. An approach for determining both the market share and average mar
ket cost of energy produced by these technologies is derived. The form
alism developed, which is based on a conditional least cost distributi
on function, can be used to correct the conventional logit treatment o
f these quantities in several existing models and to better interpret
empirical data in order to determine more realistic cost distribution
functions for energy technologies.