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CPCN for Bethesda Triangle, LLC Prepared by South River Consulting, LLC Bethesda Triangle Description of Use of On-site Electrical Generation System Introduction The Bethesda Triangle Project is a high rise apartment building located at 4835 Cordell Ave., Bethesda, Maryland 20814. The building consists of 13 stories of apartments, 4 levels of garage parking, office space on the lobby level and retail space on the plaza level. An analysis of the benefits of using the on-site standby generation equipment required for building occupancy as a hedge for the market purchase of electrical power, based on a residential profile and the projected loads for the Bethesda Triangle (BT) Project, have indicated that the utilization of the 1800 kW generation unit will provide savings on future electric purchases in a deregulated market. The on-site system will operate under this scenario, whenever the market conditions indicate that it is more cost effective to do so than purchase power on the open market. The generation system is sized slightly larger than the peak consumption that is currently projected for the project. Whenever the system comes on-line, any excess generation output may be sold back into the market or to Bethesda Triangle’s retail supplier. When the system is not operational, Bethesda Triangle will purchase its power from the market through a retail supply agreement. Confidential and Proprietary CPCN for Bethesda Triangle, LLC Prepared by South River Consulting, LLC Generation System The generation system, which was installed for the Project, is a Cummins Power Generation 2000DQKC generator set with a Power Command Control System and utility paralleling switchgear. The generator set has a prime power rating of 1825 kW at 60 Hz and generates at 13.2 kilovolts. The scope of supply is detailed in the attachments. Generator set data sheets and specifications are also included. A one-line diagram and an interconnection protection scheme for the local distribution company (PEPCO) tie in is also provided and the following includes the sequence of operation description for utilization in the market. The system ties into the existing feed to the building from PEPCO and therefore no transmission line is required. The generator and switchgear equipment are located in an enclosed room on the G1 (garage) level of the building next to the PEPCO vault as seen in the attached drawing, “G1 Gear Room”. Generation Operational Strategy The use of the generator to respond to market conditions is based on a two-part strategy to minimize electric procurement costs and extract value from the market for sales of excess generation. The generator dispatch is based on mitigation of fixed cost and extreme energy cost avoidance. The unit will produce energy anytime the marginal cost of delivered power exceeds the marginal cost of operating the unit. The energy charge component of the electric cost will be displaced whenever the generator is operating. Confidential and Proprietary CPCN for Bethesda Triangle, LLC Prepared by South River Consulting, LLC The second element of the strategy is for the project to realize revenue from the sale of the excess generation into the market as an energy resource. Utilizing existing market algorithms, the market data will be analyzed to determine the appropriate time to selfgenerate and sell the excess power into the market. Based on market conditions, operation of the generator will be limited to less than 1,000 hours per year. This limitation is driven by PJM market economics and any operation beyond this limit other than for emergency use, would have a negative financial impact. Electric Sales and Purchases Bethesda Triangle’s electric service contract will be for the supply of electric service to meet 100% of the project’s requirements. When utilizing the on-site generation, the system will be treated as a behind the meter resource, which nets the load and generation. Excess power sales for the energy will be marketed through the retail supplier or other qualified market participant. Bethesda Triangle SEQUENCE OF OPERATION Loss of Normal Power: System is given a signal to start by receipt of a start signal from the transfer pair control voltage sensing or a remote device. On receipt of this signal, the Confidential and Proprietary CPCN for Bethesda Triangle, LLC Prepared by South River Consulting, LLC generator set automatically starts, and accelerates to the rated frequency and builds up to the rated voltage. The control system verifies that the generator set is at 90% of rated voltage and frequency or more, and the breaker pair operates to connect loads to the system bus. Fail to Crank or Fail to Start: On receipt of a start signal, following a start time delay, the control system issues a command to start the engine. The control verifies that the engine is rotating when the start command is issued. If the engine does not rotate when the start command is issued, the unit stops cranking, then tries again. If the engine still does not rotate, the generator set is shut down and a “FAIL TO CRANK” shutdown alarm is issued. If the generator set cranks but fails to start after the overcrank time delay (in the generator set control) has expired, the unit will be shut down, and an alarm will sound. Fail to Synchronize: If the generator set fails to synchronize after a preset time delay an alarm will sound, but the unit will continue to attempt to synchronize until signaled to stop by manual operation of the control switches on the generator set. Fail to Transfer: The control system continuously monitors the breakers as they are issued signals to operate. If a breaker does not operate properly, the control system provides fallback operation modes to prevent operation of the generator set in parallel with the utility service for sustained periods of time. Return of Normal Power: When all of the system start signals are removed from the digital power transfer control, the system will begin a retransfer process in either an open or closed transition mode, as selected by the operator. If running in the closed transition mode, the system synchronizes the generator set to the utility, closes the utility breaker, Confidential and Proprietary CPCN for Bethesda Triangle, LLC Prepared by South River Consulting, LLC ramps down the load on the generator breaker to a minimum value, then opens the generator bus breaker. If running in the open transition mode, the system transfers back to the utility by opening the generator bus breaker, then closing the utility breaker at an operator programmed time period later. When all loads have been transferred back to the utility, the generator set operates at no load for a cooldown period. When the cooldown period has been completed, the generator set shuts down. If a system start signal is received during the cooldown period, the system immediately re-transfers to generator set power, as described in “Loss of Normal Power”. Automatic Operation - Peak Shave Mode: The peak shave mode may be selected via dry contact or locally from the Operator Interface Touchscreen. On receipt of this signal, the generator set starts, accelerates to rated frequency, and builds up to rated voltage. The PowerCommand Control monitors the generator set, and on finding the generator set at 90% of rated voltage and frequency, and in synchronism, closes the unit to the bus. The UM breaker remains closed. Once the generator set is connected to the utility, the Master Control PLC will calculate the required generator KW level using a transducer input from the switchgear. The generator will then ramp up to assume the load above the peak shave KW setting (set on the operator touchscreen). This will allow the Utility to maintain a constant load while the generator system adjusts to supply the load “peaks”. Confidential and Proprietary CPCN for Bethesda Triangle, LLC Prepared by South River Consulting, LLC Full Load Mode Selected: Once the generator set is connected to the utility, the generator will ramp up to assume the load up to the full load setting of the generator (adjusted on the generator set setup screen). If the building load is less than this setting, excess power will be exported to the utility. The #32 reverse power relay is disabled in this mode. On receipt of an unload (Peak Shave / Full Load Off) signal, the generator will gradually ramp down to a preset level, and 52-G will open. The generator set paralleling breakers will open and the generator sets will then run unloaded for a cooldown period and shut down. If there is a power failure while in the Peak Shave Mode or Full Load Mode, the utility protective relays on the UM breaker will activate a Lockout Relay which trips 52-UM. The Lockout relay must be reset at the switchgear. Confidential and Proprietary