A site-wide energy balance that includes fuel, steam, and power forms the foundation of
any energy study. Only after a base case energy balance is generated can one effectively
evaluate the impact of energy savings and fuel optimization projects on the system as a
whole, from both an economic standpoint and a pure utility balance perspective.
For example, if the steam system were not fully understood, how would one know
that an increase in waste heat steam production in one area of the refinery would not
simply result in the venting of steam somewhere else?Or, without a detailed fuel balance,
how could one determine the impact of steam use reduction projects on the fuel gas
balance when boilers are turned down, or shut down completely?
As an added benefit, the fuel, steam, and power balance discussed in this chapter
becomes an extremely valuable tool for designing new facilities for the site. For example,
a well-understood plant energy balance would help in the selection of major rotating
equipment drivers—especially when deciding between steam turbine and electric motor
drivers, which have very different impacts on all three components of the balance (fuel,
steam, and power)