An assessment of desalination technology was conducted with a view to
determining the most feasible option for a seawater desalination plant
as a thermal host for the proposed Rosarito Repowering Project in Baj
a California, Mexico. Plants based on low temperature multiple effect
distillation (LTMED), reverse osmosis (RO) and a hybrid LTMED/RO syste
m were evaluated. All three options were shown to satisfy the requirem
ents of the U.S. Public Utility Regulatory Policies Act (PURPA) for a
qualifying cogeneration facility. Subject to limitations on the accura
cy of the estimate (-5/+20%), the lowest water cost was obtained with
reverse osmosis. In addition, certain site-specific considerations suc
h as power plant dispatchability and constraints on the expansion of t
he existing seawater intake system tended to favor the RO option.