download
Post on 12-Nov-2014
223 Views
Preview:
DESCRIPTION
TRANSCRIPT
EPTdelivering breakthrough solutions
Developing Rigorous GHG Forecasts For E&P OperationsGHG Forecast Tool
John Edwards
Head of ProjectsEmissions Asset Business
Accurate GHG Forecasts: Why ?
• Company Climate Commitments
– Monitoring Progress And Making Appropriate Interventions
• Emissions Markets
– Understand Future Cost Implications
– Plan
– Make Interventions
• Increasing Focus On Carbon and Its Management.
– Likely Carbon Will have A Cost In Most Places
– Reputation
– Responsible Corporate Behaviour
15
20
25
30
35
40
45
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
Mil
lio
n T
on
nes
BP GHG Emissions From E&P Segment
Commitment 1 in 1998
Reduce Emissions By 10% by 2010
Commitment 2 in 2002
Hold 2001 Flat To 2012………
15
20
25
30
35
40
45
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
Mil
lio
n T
on
nes
Forecast
Accurate GHG Forecasts: Why ?
• Company Climate Commitments
– Monitoring Progress And Making Appropriate Interventions
• Increasing Focus On Carbon and Its Management.
– Likely Carbon Will have A Cost In Most Places
– Reputation
– Responsible Corporate Behaviour
• Emissions Markets
– Understand Future Cost Implications
– Plan
– Make Interventions
How To Produce Accurate Forecasts?
Flows Through Facility
No of Trains & Plant Loading
Performance Curve to give power requirement
No of Turbines & Loading
Part-load Efficiency Curves
0
5
10
15
20
25
30
35
40
45
0 20 40 60 80 100 120
Percentage Loading
Eff
icie
ncy
(%
)
RB211 (6562G)
Avon
Frame 5 (5371PA)
Frame 6
Frame 7
LM1600
LM2500
LM2500+
LM6000
Mars 100
Saturn 20
Centaur 50
Taurus 60
Tornado
TB5000
Performance Curveto give energy requirement
Fuel Gas Propertiesto give CO2
CO2 Profile
CO2 Cost
Energy CostEnergy Metrics
Schematic Of Forecaster Tool
Outputs
Forecasts For:
Fuel FlowFuel Cost
CO2 EmissionsCO2 Cost
Performance IndicatorsEquipment LoadingEquipment Performance
Process Modules
Compression Turbines and Drivers Pumps
Flow DataOil Flow Gas FlowGas InjectionWater InjectionFlare EstimateVent Estimate
Other DataMisc Electrical LoadsMisc Thermal LoadsAmbient ConditionsRunning StandbyDowntimeDays on Diesel FuelFuel Gas AnalysisFuel Gas PriceCO2 Price Forecast
Facility Model
Model Requires 3 Input Elements
Flow Profiles
0
20
40
60
80
100
120
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
Pro
du
ctio
n m
bo
/d
0
100
200
300
400
500
600
700
800
Inje
ctio
n &
Lif
t m
b/d
Gas Export
Oil Export
Water Injection
Seaw ater Lift
Modelling the installed equipment and its operational characteristics
Profiles of the flows that cause energy to be consumed in the major equipment
Operational factors: running standby capacity, ambient conditions, fuel composition, fuel / CO2 prices,
miscellaneous not modelled issues e.g. flare, thermal loads, general power etc
Tool converts this data entry into
• Equipment running and its loading
• Equipment efficiency and its power requirement
• Turbine loading and fuel requirement
• CO2 emissions, energy requirement profiles and associated costs
Input Screen Examples
Separate Entry Tab For Each Unit Operation
Each compressor or pump characterised by peak throughput and peak power requirement
Driver can be motor or turbine from drop down list
Driver can drive any combination of compression stages
Flow Profiles Input Tab
Gas Export and Interstage Flows
Gas Injection
Oil Export
Water Injection (2 Trains)
Flare
Vent
Diesel (for miscellaneous duties e.g. crane, fire pumps)
Period Usually annual for initial runs
Can amend inputs to give multiple scenarios in a year - increases accuracye.g. ambient temperature change, fuel change, equipment downtime etc.
Miscellaneous Data
Miscellaneous inputs e.g:-
• loads not calculated in tool eg thermal requirements
• ambient conditions
• cost data
Output screen
Illustration of typical output screen for selected period
Traffic Light Performance
Visual Indication of Installed Plant
Number of Trains In Operation
Breakdown of Power Use By Operation
Report Options: Energy, CO2, Cost
Detailed Report by Period
Button for ChartsData Export etc
Confirmation of Accuracy and Application
InstallationPredicted
CO2Actual CO2 Difference %
A 455,764 448,000 7,764 1.7%
B 269,961 253,953 16,008 5.9%
C 286,424 288,570 -2,146 -0.7%
D 211,389 202,679 8,710 4.1%
E 543,156 543,007 149 0.1%
• Tool tested “blind” using historical production data to give forecast and compared with what was reported
• Results very acceptable, within 5%, once main scenarios accounted for
• Usually needed a couple of hours to produce the results if accessed the right people from the operation: process engineer / production planning
• Once configured, very quick forecast updates available as production / operational changes are predicted.
• Future GHG forecast “error” will be due to differences in production / operational actuals v forecast, not GHG methodology
Initial Lessons Learned
• Great value in having an accurate, consistent, robust, transparent model for
ghg forecasting.
• Concern about basing calculations on daily flows = annual flow / 365
when there were usually a number of periods in the year where the operating
conditions would have influenced performance
• Therefore needed scenario modelling and aggregation: Excel output
• For some facilities we needed more functionality
•e.g. interstage gas flow, spinning reserve etc
• A lot of invaluable information being generated but not displayed.
• Tremendous potential for option appraisal in facility design
• Needed To Develop a “Mk 2” updated version
Who Will Use?Initially GHG Forecaster
• Designed to get a balance between simplicity and accuracy
• Focus on use by Energy/ Environmental Engineer
– Minimal training required
– Can then do own options appraisal & sensitivity studies
• Does not need Process/Mechanical Engineer to run
– Already incorporated in model
• Max ½ day population and running
Updated Tool
• Concept Developer
• Project Development Team
• Operations Engineer
Use Of Forecaster For Option Appraisal
ProductionForecasts
Concepts & Options Appraisal
Option 1
Option 3
Option 2 BAT
Technology Options
Power Import CCGT GT vs Motor Drive No of trains
Sensitivities
Plant & Ops OptionsDifferent Gas TurbinesSpinning ReserveUncertaintiesProduction Forecasts CO2 Trading Value Fuel Price Fuel Gas CompositionDays on Diesel
Outputs
Fuel & CO2 CostEnergy KPIsPlant Load ProfilesEmissions Profiles
Use Of Forecaster For Option Appraisal
Example of a North Sea Facility:
• Mature asset
• 2 oversized turbine generators, both running for security of supply
• Turbine driven gas export and “mid life” compression
• EUETS trading exposure $1m
• Asset model developed for GHG forecasting
Consider impact of :
• Right size turbines: Power Generation
• Single turbine operation: Power Generation
• Change from Mars turbines to electric compression on LP (midlife compressors)
Base Case: Current Operation
Turbine 34% loaded
MP Compression stage on recycle: HP is OK
If motor driven soon able to turn of a train
CO2 Emissions Forecast
Saving Potential
Driver Change 15kTe/y
Motor Drives 22kTe/y
Single GT Op 23kTe/y
All Electric 62kTe/y
580,000
600,000
620,000
640,000
660,000
680,000
700,000
2009 2010 2011 2012
To
nn
es C
O2 Current
Driver Change
Motor Drive
Single GT
All electric
Saving From MP Compressor Shutdown
Analysis Shows
• Single turbine generator operation would save $4m / year, worth investing up to $20m capex eg standby power from adjacent platform
• Questionable decision to provide turbine driven mid life compressionMotor drive would save $3.8m / year, could spend up to $20m capex
• Generally hard to justify driving different stages with single shaft over life of operation
• An all electric platform would save $11m/y now in CO2 and fuel costs
0
2
4
6
8
10
12
Driver Change Motor Drive Single GT Op All Electric
Mill
ion
Dol
lars
Fuel
CO2
Fuel Cost$7/mmBtu
CO2 Cost$29/ tonne
Conclusions
• Possible To Achieve GHG Forecasts Within 5% Of Actual Emissions- subject to production forecasts being correct- for conventional centralised, eg offshore, operations
• Invaluable Having Consistent & Transparent Estimation Methodology
•Forecast Updates Take A Few Minutes- ie converting throughput forecasts to GHG forecasts
• Excellent Tool For Option Appraisal In Concept / Project Development- technology selection, driver selection, number of trains- inclusion of energy & CO2 costs enable quick viability assessment
- enables a life cycle approach to project development
• Has Application In Existing Operations Optimisation- standby plant operation, plan compressor re-wheeling, reducing running GTs- enables high level performance benchmarking
• Off The Shelf Product Available To All E&P Companies- Tool released through PI Energy & Emissions
top related