Page 208 - Sustainable On-Site CHP Systems Design, Construction, and Operations

CHAPTER 11

Electrical Design

Characteristics and Issues

Kelly J. Mamer

David C. Rosenberger

Jeffrey S. Hankin

he maximization of CHP energy use requires an extremely well-designed
mechanical and electrical system, with a number of design considerations taken
Tinto account for each interconnected system. Regarding the electrical system, the
risks for a poorly designed system go far beyond system failures, as costly and debili-
tating as that may be. For example, utility companies have detailed requirements for
export of owner-operator–generated power onto their grid. This becomes extremely
important in the event of a fault on the utility side of the line, with the potential that the
CHP system may be feeding back into a fault and creating a scenario where life safety
is at risk. CHP systems have many applications and options, and the generation of elec-
tric power is typically a key to the applicability of these systems. However, the electrical
system design must allow the CHP facility owner to utilize the generated electric power
in a safe and efficient manner.
This chapter discusses a number of specific electrical design issues; the next few para-
graphs are a summary of these issues. One issue is the electric power generation itself and
its delivery to properly sized, configured, and protected switchgear equipment. The prin-
cipal factor, excluding safety concerns, among all requirements of a CHP system is redun-
dancy and reliability at the CHP plant and further upstream when distributing electrical
power onto the utility grid. A robust and redundant electric power system requires switch-
gear which allows the CHP plant operator various options for connection and maintenance
of the prime mover as well as for an efficient distribution system for downstream loads.
In concert with the power distribution equipment, a well-defined control and
energy management system works to optimize plant energy demands as well as help
improve the efficiency and availability of the CHP plant. As past CHP and other indus-
trialized plants experience shows, investing in a robust and reliable control and energy
management system has many significant operational and economical advantages.

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