CASE STUDY
Onshore gas plant
Management of energy performance.
Client
Industry
Lead consultant
Cost savings
Largest source of
GHG emissions
GHG
reductions
Onshore Gas
Plant
Oil and gas
Brian Innes
5% of total
energy use
Vented methane
20%
Energetics assisted the operator of an onshore gas plant to
identify a range of energy saving and Greenhouse gas
(GHG) abatement opportunities. Despite the large demand
for gas by the compressor and generator turbines, the study
showed that the largest point source of GHG emissions was
the methane remaining in nitrogen vented from a nitrogen
rejection unit. Technologies borrowed from coal mining
may offer a means of reducing emissions from this source.
Outcomes
reductions in spinning reserve.
Understanding the energy and GHG
footprint
Through the use of its robust analytical
tools, Energetics was able to quantify
the major energy users and sources of
GHG emissions. We showed that the
largest contributor to the GHG footprint
was vented methane. Our custom
Energy-Mass Balance (EMB) tool
provided the site with its first view of
energy demand across all its
operations.
Establishing the priority GHG
abatement opportunities
Using the EMB tool to build the
analysis of energy use and GHG
emissions, a range of abatement
opportunities were found. Excluding
the gas turbines, cost effective energy
savings amounted to 5% of total
energy use. The single largest source
of energy waste was poor gas turbine
operation primarily due to underloading of turbines. Larger savings
could be obtained by altering the
operation of the gas turbines but this
required a comprehensive risk analysis
to explore the likely impact of
Management Plan to identify emissions
sources and options to reduce emissions.
GHG reductions amounted to
20% of emissions and relied on
technologies to oxidise
methane in Nitrogen Rejection
Unit vent gas.
Energetics undertook this assessment to
identify initiatives and implement
processes that would ensure energy
efficiency and energy source substitution
opportunities were integrated into the
business. The focus of the assessment
was the compilation of an energy
baseline, and the analysis of likely areas
for improvement.
Strengthening GHG reporting
Comprehensive analysis of
energy use
The site had a range of obligations to
report energy use and GHG emissions.
Utilising our deep knowledge of the
regulation and processes associated
with GHG inventory reporting,
Energetics provided practical advice on
the necessary improvements to metering
and monitoring needed to achieve the
target accuracy for GHG inventories.
Background
The operator of an onshore gas plant
sought to assess the energy
performance of its assets in line with its
corporate requirements. This included
the development of an Energy & GHG
Energetics has a range of custom tools
developed for upstream oil and gas
production, which allows us to quickly
develop energy baselines, identify
improvement opportunities and quantify
savings.
The analysis of the site began with the
development of an EMB. As occurs at
many gas plants, the metering of fuel gas
beyond the main fuel gas meter was very
limited. Energetics has a range of tools
that were applied to validate the indicated
flow of fuel gas to the turbines and to the
other gas users (thermal oxidiser, glycol
strippers, MDEA regenerator). The goal
was to obtain closure of the fuel gas
© ENERGETICS PTY LTD 2012 | AFSL329935 | WWW.ENERGETICS.COM.AU
ENERGETICS IS A CARBON NEUTRAL COMPANY
CASE STUDY Cont.
Onshore gas plant
Management of energy performance.
balance to ±5%. Our analysis
highlighted performance issues with
the gas turbines. The major issue was
under-loading of its large compressors.
In addition, the site was advised to
assess its cleaning regime.
Robust identification of
opportunities
Energetics reviewed the site’s energy
baseline, which highlighted areas
where energy was used inefficiently.
Energetics used a process not unlike a
hazard and operability study (HAZOP).
We systematically reviewed the
process flow diagram to identify
opportunities for better heat integration
or the utilisation of waste heat. For
instance, the study highlighted an
opportunity to use surplus heat in the
heating medium circuit to preheat air to
the thermal oxidiser.
Challenges - the myth of
free energy
In common with many similar facilities,
there was a view at the site that gas was
effectively free. This view failed to
account for the opportunity cost of
additional product sales, the royalty
charges payable to the Government and
in the future, costs due to GHG
emissions.
Calculating the opportunity cost of fuel
gas can be complex. Energetics helps to
simplify this for clients by using a variety
of approaches and tools that we have
successfully applied to a range of
different clients and facilities.
Energetics has worked with
Australia’s largest energy users for
over 25 years and helped many
with their energy and carbon
strategies.
For more information on how
Energetics can support your
company, contact:
WA: Brian Innes
(08) 9429 6400
[email protected]
We also assessed the site’s approach
to energy management using our
®
One2Five tool which evaluates key
management processes and systems
on a 1-5 scale of maturity. This
highlighted a number of areas for
improvement relating to measurement,
KPIs and targets.
© ENERGETICS PTY LTD 2012 | AFSL329935 | WWW.ENERGETICS.COM.AU
ENERGETICS IS A CARBON NEUTRAL COMPANY