300 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1958 
ment and likely to influence decisions on choice of process and planning 
of the conversion plant. In view of these and other considerations, the 
U.S. Congress recently authorized the construction of five demon- 
stration plants, two of which shall have a capacity of at least 1 million 
gallons per day. The five plants, to be built at both seashore and in- 
terior sites, will provide invaluable information on the cost and value 
of large-scale saline-water conversion. 
Compared to other developments such as atomic energy, the amount 
of research and practical development effort devoted to saline-water 
conversion has been very small indeed. Nevertheless, considerable 
commercial utilization has been made of the results, as shown on 
pages 92 and 104, Department of the Interior Report on Saline Water 
Conversion for 1957[3]. 
In the matter of cost of conversion, detailed treatment is being given 
in the paper at this Symposium by Prof. Everett D. Howe of the 
University of California. In more brief consideration of costs here, 
we are reminded that early in the research program, it was found 
that few engineers or industrial firms used similar factors for com- 
puting costs. Some inventors and others omitted many of the factors 
when estimating costs. 
Asa practical matter, therefore, the Office of Saline Water concluded 
that a standard cost-estimating procedure should be developed and 
that has been done. Copies are available from the Office of Saline 
Water, Department of the Interior, Washington 25, D.C. The method 
is flexible enough to be used for any locality by adjustment of the cost 
factors. 
The following table contains estimates of cost per 1,000 gallons by 
various saline-water conversion processes in the United States, with- 
out credits for sale of power or other byproducts. 
TABLE 1.—Cost estimates per 1,000 gallons 
1957 designed or projected | 1960-70 anticipated 
1952jexisting installations installations (if further research 
is successful) 
Sea water Brackish 35,000 5,000 35,000 5,000 
35,000 5,000 p.p.m. p.p.m. p.p.m. p.p.m. 
p.p.m p.p.m 
Less Less 
than— than— 
Distillation (including solar) -_| $2. 00-$5.00 | $2. 00-$5.00 | $1. 00-$3.00 | $1. 00-$3. 00 $0. 50 $0. 50 
Membrane processes.__------- (2) (2) 6.00 . 80 1.00 . 25 
Freezing (Jou io men zesery (2) (2) (2) (2) . 50 . 50 
Ofhers-o2csec.e 2) 2 eee (2) (2) (?) (?) -50 25 
1 p.p.m.—parts per million. 
3 Not developed. 
