6.0 ELECTRIC TRANSMISSION AND STEAM SENDOUT

6.1 Electric Transmission

For a merchant plant, system reliability impacts (and system upgrades to alleviate the same) are determined pursuant to a process under the auspices of the NYISO. In addition, the Siting Board requires that the Application provide a discussion of the "benefits and detriments" the Project would have on the electric transmission system. 16 NYCRR 1001.1(b). The discussion of electric interconnection and the transmission System Impact Study is found in this section. Electric and magnetic field studies are also addressed below.

The Project site is adjacent to several underground 345 kV and 138 kV circuits. TGE will study interconnections at both 345 kV and 138 kV at several substations in Brooklyn as well as Queens and Manhattan - Farragut, Greenwood, East 13th Street, and Rainey/Vernon. TGE will explore the use of available conduits to minimize street openings by Con Edison. Con Edison operates the transmission and distribution systems in all of New York City except the Far Rockaway Peninsula. The 345 kV and 138 kV lines in the system are shown in Figure 2-1.

6.2 Proposed Steam Sendout

The Project site is located across the East River from the Con Edison East River complex, which includes the East River Generating Station and an auxiliary boilerhouse. This is one of the principal hubs of the Con Edison steam system. By interconnecting at this location, the Project will have the potential to sell steam to Con Edison's steam network.

TGE is proposing that the Project include steam infrastructure. However, it is important to underscore that the Project is feasible as a combined cycle power plant without steam sendout. Steam sendout is a part of the proposed design, but it is not integral to the proposed design. With steam sendout, this already state-of-the-art generating facility increases to one of the highest, if not the highest, efficiency facilities in New York City. It is TGE's intent to build a record in the Article X proceeding that will allow it to be approved as a combined cycle facility with steam sendout or as simply a combined cycle facility.

TGE has met with Con Edison officials regarding the Project's interconnection with the steam system. It is TGE's intention to offer Con Edison the right, at its sole option, to purchase steam from the Project at a specified demand for a given point in time. TGE anticipates proposing a "take and pay" agreement, thereby allowing Con Edison to purchase steam at its election, without a minimum "take or pay" agreement. If Con Edison opts not to purchase steam, TGE will produce additional electricity through its steam turbine-generators and sell it into the marketplace.

6.3 Information Requirements and Methodology

TGE has consulted with Con Edison and will submit a draft scope of study to NYISO staff, and also to the DPS, to every regulated transmission owner in New York State as well as the adjacent ISOs - the PJM Interconnection and ISO-New England. Upon approval of the scope by the NYISO Staff, ABB Transmission & Distribution will conduct a system reliability impact study (SRIS) for the Project's interconnection with the system. The study will be done using the interconnection criteria established by NYISO. The thermal, stability, voltage and short circuit effects on the system will all be studied. The results of these studies will identify any needed upgrades to the transmission or substation equipment in order to reliably interconnect the plant. The preferred interconnection configuration and any associated upgrades will be presented in the Article X Application. They will be based in large part on the findings of the SRIS.

A somewhat detailed description of each major component of the SRIS is provided in TGE's proposed Stipulation 3 (in Appendix B), with further detail to be provided in the SRIS proposed scope, which will be filed for approval with NYISO Staff. The primary issues to be studied are also described below in layman's terms.

Thermal Analysis is concerned with the temperatures of transmission wires ("conductors") under conditions of high stress. The period of concern is typically the summer, when transmission lines carry the greatest current, yet cannot easily cool due to high ambient temperatures. It is important that at key points of constraint in the system ("interfaces"), the thermal limits (which are set by maximum current) are not exceeded.

Voltage Analysis refers to the short-term effects of a surge or dip in transmission line voltages because of sudden outages or other problems ("contingencies"). When and if a facility such as the proposed Project is suddenly unable to deliver electricity into the grid, it is important that voltage be preserved at the nearest pertinent upstream and downstream interconnection points ("buses").

Stability Analysis considers the ability of the Project to generate its output to the transmission grid in light of faults or other severe disturbances to the system. A variety of the disturbances are considered.

Short-Circuit Analysis is an assessment of the adequacy of major local circuit breakers at potentially affected substations. Each circuit breaker's existing rating will be compared to a required "fault duty", and in cases when the fault duty is greater than existing rating, either upgrades or alternate measures would typically be recommended.

6.4 Electric and Magnetic Fields

The transmission of alternating current (ac) electricity produces electric and magnetic fields. The voltage of a power line produces electric fields. The voltage difference between the conductors, the ground and nearby objects directly relates to the strength of the electric fields. The strength of electric fields is typically measured in units of kilovolts per meter (kV/m). The current flowing through power lines or other conductors generates a magnetic field. Magnetic fields are typically expressed in units of milligauss (mG). Electric and magnetic fields are commonly referred to by the abbreviation EMF.

The Public Service Commission has established guidelines for EMF. As proposed in Stipulation 3, TGE will estimate EMF changes, if any, resulting from its new electrical interconnections. The Application will then present calculations of post-Project electric and magnetic field levels at the same locations. An applicability evaluation and a comparison of predicted EMF levels along Project electrical interconnections with the above-cited standards will be included.

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