(GP/GT) for Additional Water Supply in the Lower Rio Grande

1II-36
Based on this comparative data the economic evaluation definitely favors the RO over the EDR system, in part because
the use of blending in the RO system implies a smaller plant to yield the same amount of product water. However, as
stressed in Mr. Reahl's comments and footnotes, the cost projections do not include the capital and O&M costs and
associated energy requirements for the raw water wells, piping to desalter, brine transfer to deep injection wells nor the
deep injection wells themselves. Mr. Reahl's comments also stress that the impact of adding these components to the
evaluation would serve to narrow or possibly eliminate the cost differentials as between the RO and EDR alternatives.
In summary, in view of the potential of narrowing or eliminating the cost differential, coupled with the previously
established technical feasibility advantages to EDR, it is appropriate to carry both the RO and EDR alternatives forward
to Step 3 - Pro Forma Analysis.
Energy Forms
Because of the aforementioned limitations on the application of the E(B) and E(P) energy forms, coupled with only a
limited amount of available information regarding the economics associated with these forms, a detailed comparative
analysis of these three alternatives is simply not merited nor accomplishable at this time. Instead, outlined below are very
order-of-magnitude projections of representative costs in terms of $1 /KW, for applications associated with these three
forms, along with an indication of the sources of information from which they were calculated. Such projections ar
presented as follows:
Order-of-Magnitude
Energy Form Application Source of Information of Cost +
E(B) Kalina-Cycle System 12 See note (I) on page_ $ 1572IKW
E(B) Cascade Rankine Cycle See note (1) on page _ $2871/KW
E(G) Gas Turbine Generators Stewart and Stevenson Data 6OO/KW
(3MW)
E(P) Impulse (pelton) type See note (2) on page _ $ 240/KW
turbine with induction
type generator and controls
E(G) Conventional Thermoelectric Published Literature $1200 - 2000/KW (as a comparison)
It should be noted that all of the projected cost figures presented above are exclusive of the cost of the GP/GT well and
appurtenances.
In summary, notwithstanding the apparent substantial comparative economic advantage of the application of E(P) over
E(G), only the application of E(G) is to be carried forward into Step 3 - Proforma Analysis because of (a) the much
greater quantities and (b) the certainty of its technical application. Notwithstanding, based upon the comparative cost
information above, it seems very worthwhile to further investigate the application of E(P) to aid in reducing the net cos
of on-site power generation in an operating complex. This aspect definitely merits a continuation of the present effort.