Business: Industrial
Setting up an Energy Management Program
1.3 Understanding the audit results
be two likely energy audit outcomes:
• Establishment of a foundry-wide energy management
program; and
• Prioritization of an
energy efficiency improvement project, indicated by the
audit, for the energy management program
to address.
With the delivery of the audit report, the process of key importance – an
energy audit – has been concluded. The diligent and professional work
of the energy auditors has produced a report with results reflecting that particular
slice of time when the audit was conducted. Although not absolute, the results
can be extrapolated with reasonable accuracy to the foundry’s average
operating conditions. The management team should review the audit report with
this in mind and decide on the course of action to be taken.
Energy audit results
may offer very concrete directions regarding energy management. For example,
an aluminum foundry may wish to consider switching fuel sources for melting,
particularly if a mass balance was also undertaken.
Melting losses for aluminum, typically 7% with older gas-fired furnaces,
can be reduced to 0.5% with electrical melting. Electricity is a more expensive
energy source. Nevertheless, when the annual cost of lost aluminum (at, say,
$1.60/kg) as well as the positive impact from improved quality of castings
(i.e., lower reject/scrap losses, reduced rework) are considered, the payback
from switching to electricity may be found to be very attractive.