Prime Diesel Power Plant Operation: Island, Base, Standby and Service

The critical factor in running a diesel power station as the prime source of electricity for a heavy industrial process - such as gold mining for instance - is to run the power station in four separate modes, all at the same time. These include "Island Mode", "Base Mode", "Standby Mode" and "Maintenance Mode".

The first bay of generators should be operated in "Island Mode" (IM). Island Mode is achieve through the use of paralleling auto-synchronizing electrical switchgear that matches voltage, frequency and kW between 2+ separate diesel generators. These units run in Island Mode in that their power output (kW) "floats" up and down depending on the power required by the specific process at that time. Auto-Synchronizing gear will call for more generators to start up as needed when pre-set parameters are exceeded. Likewise, switchgear will shut down generators when pre-set ranges (ie. 800kW - 1200kW) are not met - keeping each island generator running as close to its optimal kW output level as practical. This bay is critical as the loads fluctuate tremendously and suddenly in many industries and these generators must react quickly. The best generators for IM operation are "high speed" 4 pole, 1500/1800 RPM machines as their reaction times are much more optimal.

The second bay of generators should be operated in "Base Mode" (BM). Base mode is achieved when a set of 2+ generators is programmed via their auto-synchronizing paralleling switchgear control panels to operate at precisely the electrical (kW) output level that achieves optimal l/kW/h fuel efficiency. Whereas IM sets fluctuate output depending on what is required, the BM sets produce a static level of output - saving substantially in fuel costs per year. These generators can either be high speed units or, more optimally, slow speed "thumpers" that are even more fuel efficient and robust. 

The third bay of generators should be operated in "Standby Mode" (SM). These generators in standby mode have been serviced and are ready to start as soon as loads require them to be, or in the case that a IM or BM set fails. It is critical for safety reasons that Standby Sets not be serviced while in Standby Mode as this can be fatal. A rigid and proactive safety protocol must be kept in order to ensure the health of all power plant personnel. 

The fourth and final bay of the power plant should be separated into "Maintenance Mode" (MM). Maintenance mode is simply the status a generator set is placed into when being serviced or repaired. The key is to keep prime power diesel generators in this bay for the most minimal periods of time possible. This can be very difficult in remote areas of the world as critical spare parts are often several weeks away and repairs can be delayed. 

One of the key elements of managing a power plant is the elements that go into balancing a power station's "Spinning Reserve". The spinning reserve is the "extra power" that a power plant produces but doesn't use that is required in case either (a) a generator fails suddenly and the others must immediately react, or (b) the output loads increase suddenly and the IM and BM generators must immediately and suddenly produce substantially more power. 

Spinning Reserve must be monitored on an hour-by-hour basis by a qualified, trained Field Technician who is trained in Fuel Efficiency Optimization. USP&E offers training and staffing resources to this end through our mechanical, environmental and electrical optimimum output load management courses. 

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