fees. It also does not include the cost to transport the water to the plant, or
incidental or contingency costs. However the cost to develop the site is included
and is estimated to be 5% of the material and construction costs.
The amortization factor is calculated as,
i( + i)"
a = (4.8)
where i is the interest rate and n is the plant life. The annual fixed costs are calculated as,
A~fixed = (a)(DC), (4.9)
where DC is the direct capital cost. Lastly, the annual labor cost is evaluated as,
Alabor = (7)( f)(m)(365), (4.10)
where y is the specific cost of operating labor and m is the plant capacity (m3/day).
Therefore the total annual cost can be calculated as,
ALtotal = Afixed + Alabor (4.11)
It should be noted that the cost of the waste heat, for this case in the form of heated air, is
not included since it is waste that would have otherwise been discarded into the
environment. Therefore the unit product cost of the system is calculated as follows,
A,, Aos (4.12)
""tpf-m-365
Table 4-2 summarizes the estimate of the direct costs for a full scale diffusion driven
desalination facility operating in conjunction with an industrial plant. The analysis shows
that the production cost, neglecting the electricity charges, is between 0.19-0.36 $/m3 I
terms of $/103 gal the production cost is 0.72-1.34 $/103 gl
The fresh water profit is the most important consideration in the analysis of the
DDD facility. One of the most expensive operating costs is the pumping power required