1Opportunities for Methane EmissionsReductions from Natural GasProductionLessons Learnedfrom Natural Gas STARProducers Technology Transfer WorkshopDevon Energy andEPA’s Natural Gas STAR ProgramFort Worth, TXJune 6, 20062AgendaSmart Automation Well VentingMethane LossesMethane RecoveryIs Recovery Profitable?Industry ExperienceDiscussion QuestionsReduced Emissions CompletionsRusty Werline, Devon Energy3Smart Automation Well VentingAutomation can enhance the performance of plungerlifts by monitoring wellhead parameters such as:Tubing and casing pressureFlow ratePlunger travel timeUsing this information, the system is able to optimizeplunger operationsTo minimize well venting to atmosphereRecover more gasFurther reduce methane emissions4Methane LossesThere are 390,000 natural gas and condensate wells(on and offshore) in the US1Accumulation of liquid hydrocarbons or water in thewell bores reduces, and can halt, productionCommon “blow down” practices to temporarilyrestore production can vent 80 to 1600 Mcf/year2tothe atmosphere per wellEstimate 9 Bcf/year methane emissions from U.S.onshore well venting11 - Inventory of U.S. Greenhouse GasEmissions and Sinks 1990 - 20042 – Mobil Big Piney Case Study 19975What is the Problem?Conventional plunger lift systems usegas pressure buildups to repeatedlylift columns of fluid out of wellFixed timer cycles may not matchreservoir performanceCycle too frequently (high plungervelocity)Plunger not fully loadedCycle too late (low plunger velocity)Shut-in pressure can’t lift fluid to topMay have to vent to atmosphere to lift plungerSource: Weatherford6Conventional Plunger Lift OperationsManual, on-site adjustments tune plunger cycle timeto well’s parametersNot performed regularlyDo not account for gathering line pressure fluctuations,declining well performance, plunger wearResults in manual venting to atmosphere whenplunger lift is overloaded7Methane Recovery: How Smart AutomationReduces Methane EmissionsSmart automation continuously varies plunger cyclesto match key reservoir performance indicatorsWell flow rateMeasuring pressureSuccessful plunger cycleMeasuring plunger travel timePlunger lift automation allows producer to vent well toatmosphere less frequently8Automated ControllersLow-voltage; solar recharged batterypowerMonitor well parametersAdjust plunger cyclingSource: WeatherfordRemote well managementContinuous data loggingRemote data transmissionReceive remote instructionsMonitor other equipmentSource: Weatherford9Plunger Lift Cycle10Methane SavingsMethane emissions savings a secondary benefitOptimized plunger cycling to remove liquids increases wellproduction by 10 to 20%1Additional 10%1production increase from avoided venting500 Mcf/year methane emissions savings foraverage U.S. well1 – Reported by Weatherford11Other BenefitsReduced manpower cost per wellContinuously optimized production conditionsRemotely identify potential unsafe operatingconditionsMonitor and log other well site equipmentGlycol dehydratorCompressorStock TankVRU12Is Recovery Profitable?Smart automation controller installed cost: ~$11,000Conventional plunger lift timer: ~$5,000Personnel savings: double productivityProduction increases: 10% to 20% increased productionSavings =(Mcf/year) x (10% increased production) x (gas price)+ (Mcf/year) x (1% emissions savings) x (gas price)+ (personnel hours/year) x (0.5) x (labor rate)$ savings per year13Economic AnalysisNon-discounted savings for average U.S. Well =(50,000 Mcf/year) x (10% increased production) x ($7/Mcf)+ (50,000 Mcf/year) x (1% emissions savings) x ($7/Mcf)+ (500 personnel hours/year) x (0.5) x ($30/hr)- ($11,000) cost$35,000 savings in first year3 month simple payback14Industry ExperienceBP reported installing plunger lifts with automatedcontrol systems on ~2,200 wells900 Mcf reported annual savings per well$12 million costs including equipment and labor$6 million total annual savingsAnother company shut in mountaintop wellsinaccessible during winterInstalled automated controls allowed continuousproduction throughout the year11 - Morrow, Stan and Stan Lusk, Ferguson Beauregard, Inc. PlungerLift: Automated Control Via Telemetry. 2000.15Discussion QuestionsTo what extent are you implementing thisopportunity?Can you suggest other approaches for reducing wellventing?How could this opportunity be improved upon oraltered for use in your operation?What are the barriers (technological, economic, lackof information, regulatory, focus, manpower, etc.)that are preventing you from implementing thispractice?