Why Electric Compression or otherwise why still Gas Engine driven Compression



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Why Electric Compression or otherwise why still Gas Engine driven Compression Gas/Electric Partnership Special Workshop Electric Compression Economics, August 27 2009, Houston MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 1

Overall efficiency comparison Electric motor shaft efficiency Inlet Exhaust Gas turbine shaft efficiency Best available ISO efficiency 36% Corrections for Inlet & exhaust systems: 0.98 Auxiliary loads: 0.99 Temperature (-40 to +40 C) 1.05-0.90 Part load: 1.00-0.60 / o 1.10 1.05 1.00 0.95 ISO Efficiency 15 C, 1 Bar (100 kpa) Actual shaft efficiency 36% - 19.0% 0.90-40 -30-20 -10 0 10 20 30 Ambient Temperature C is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 2

Fundamental changes in the energy market The situation until late 80s Since the gas turbine demonstrated its reliability in industrial applications in the late 50s/early 60s, it has been the most widely used driver for gas pipeline applications in the mid to large power ranges. Smaller power requirements have been shared with gas engine reciprocating compressors. Although electric drives have long been commonplace on liquid lines, until recently they have rarely, if ever, been used for gas pumping. The reasons for this are well known: The gas pipeline/storage companies reluctance to be dependent upon an external source of power being supplied by a competing industry The strongly regulated electricity and gas market The cost of electric power compared with gas. The situation since early 90s has undergone fundamental changes in a process which is still ongoing in North America and in Europe. Deregulation of the gas and electric utilities has on the one hand caused the pipeline companies to make their systems more efficient and on the other has led to a significant reduction in the cost of electric power. The move from nuclear to gas fired power stations has made the two industries become more dependent upon each other. (present situation in europe) Gas and electricity are converging commodities and futures in both are traded on stock exchanges. This development has led to the formation of energy corporations as opposed to gas or electricity utilities. (present situation in europe) is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 3

Technologies Gas Transport / Storage market Gas Transport Application Gas Turbine driven Centrifugals Gas Engine RECIP s Electric Motor driven Centrifugals Electric Motor driven RECIP s Gas Storage Application Gas Engine RECIP s Eletric Motor driven RECIP s Electric Motor driven Centifugals Order of importance Gas Transport Application Electric Motor driven Centrifugals Gas Turbine driven Centrifugals Electric Motor driven RECIP s Gas Storage Application Electric Motor driven Centrifugals Gas Turbine driven Centifugals Electric Motor driven RECIP s clear tendency to EM driven centrifugals, RECIp s only used in case flow s are too small for centrifugals is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 4

Fundamental evaluation criteria s to make the decision for Gas Engine/Electric Compression Economical evaluation based on a full Life Cycle Cost analysis has to be performed for all alternative technologies CAPEX- Analysis: OPEX-Analysis: MAEX-Analysis: considering all overall installation costs, like costs for compression train, building, grid connection Install.&Comm.,Permit costs for energy, personnel, buildings, emmissions, interest rates, downtime Fix Costs spare parts, personnel, downtime The following spreadsheet shall be regarded as a guideline, which aspects have to be considered for such an overall qualitive LCC analysis from equipment suppliers point of view. Variable Costs is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 5

CAPEX Comparison of Different Turbo Compressor Train Concepts Train I Train II Train III GT - TC LS EM - Gear - TC HS EM - TC CAPEX for Compressor train Centrifugal Compressor 0 0 0 Driver (GT,VSDS, EM) -2 1-1 Gear / (Gear not needed) -1 (2) -1 (2) Bearing System 0 0-2 Lube/Control/Working Oil system -1-1 2 Dry Gas Seal System -1-1 2 (Capital) Spare Parts -1-1 1 CAPEX for Plant TC Building (area / height) hazardous area -2 1 2 VFD Building (area / height) non hazardous 2-1 -1 Power Supply Installation (Fuel Gas Piping / 1-1 -1 Electrical Cable) Oil System Air Cooler -1-1 2 Equipment Installation & Commissioning -2 1 2 weighting of train characteristics with each other in respect to capital investment costs (+2 most beneficial, -2 less beneficial ) is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 6

CAPEX Comparison of Different Turbo Compressor Train Concepts continued Train I Train II Train III GT - TC LS EM - Gear - TC HS EM - TC CAPEX for Building Foundation Size / Civil Works -1 1 2 Interconnecting Piping of Lube / Control / Working -1 1 2 Oil to Air Cooler Noise mitigation -2-1 1 Interconnecting Piping DGS -1-1 2 Crane Capacity -1 1 2 CAPEX for Auxiliaries Intake Filter System -2 2 2 Fire and Gas Detection System -1 1 1 Emission Control -1 1 2 Harmonic Filters (LCI only) 2 (-2) 2 2 Environmental related costs VFD Cooling System Noise Emission 2-1 -1 Oil Cooling System Noise Emission -1-1 2 Fulfillment of emission regulations -2 1 2 Emission Credits -2 1 1 Permitting Costs -1 1 2 weighting of train characteristics with each other in respect to capital investment costs (+2 most beneficial, -2 less beneficial ) is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 7

OPEX/MAEX Comparison of Different Turbo Compressor Train Concepts Train I Train II Train III GT - TC LS EM - Gear - TC HS EM - TC Train full load cycle efficiency LOW due to low driver efficiency Train part load efficiency LOW due to low driver efficiency. All trains experience reduced efficiency in throttling mode (recycle) at very low flow. HIGH due to high driver efficiency HIGH driver efficiency is nearly constant at varying power levels. All trains experience reduced efficiency in throttling mode (recycle) at very low flow. Restart capability after forced shutdown and start density 2 to 3 hour delay for restart due to Restart ability varies with motor driver thermal soak. Limited number design. Limited number of restarts of restarts per hour. per hour. Load assumption Approximately one-half hour after successful start. Sensitivity to site conditions Available power reduced with increase in elevation, temperature, and humidity Ability to start and come to full speed under load. Full power available at all site conditions HIGH due to high driver efficiency HIGH driver efficiency is nearly constant at varying power levels. All trains experience reduced efficiency in throttling mode (recycle) at very low flow. Less critical due to incread speed range Immediate restart. No limit on number of starts per hour. Ability to start and come to full speed under load. Full power available at all site conditions is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 8

OPEX/MAEX Comparison of Different Turbo Compressor Train Concepts continued Train I Train II Train III GT - TC LS EM - Gear - TC HS EM - TC Controllability Reasonably good, but depends on firing temperature and heat distribution Speed controllability less accurate due to frequency adjustment range 0-60Hz(+/- 0.5 Hz) (200 rpm) Excellent speed controllability due to high frequenzy operation at about 200 Hz (+/- 0.5Hz) (30 rpm) Ease of remote operation Good Better Excellent ( all electric concept) Speed control range typically 70-105% typically 70-105% 30-105% Sarting reliability Good Excellent Excellent Auxiliary consumption Lube oil, lube oil filter media, inlet air filter media, power for lube oil pumps, lube oil cooler fans. Nitrogen required for seal gas buffering. Instrument air consumption, for filter/purge pulse cleaning. Lube oil filter media, power for lube oil pumps, lube oil cooler fans. Nitrogen required for seal gas buffering. Nitrogen required for seal gas buffering. Instrument air consumption, for motor purge and motor pressurisation needed Cooling gas filter media. Reduced instrument air consumption due usage of only one TCV for motor cooling. No air purge requirements. AMB power supply. is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 9

OPEX/MAEX Comparison of Different Turbo Compressor Train Concepts continued Train I Train II Train III GT - TC LS EM - Gear - TC HS EM - TC Eshaust emissions Seal gas must be vented or flared; Seal gas must be vented or flared. Zero local emissions. CO2 and NOx emission. Maintenance costs higher lower lowest Unit availability lowest high highest Unit reliability lowest high highest Ability to trade carbon credits lowest high highest Fuel/Energy costs Function of local cost of electricity Risk of stricter Furure Emission Regulations high low low Insurance risk higher lower lower is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 10

Life Cylce Costing: Definition Common Definition Classification and summation of single cost factors of a examined object within its time of life into following fields acquisition (CAPEX) operation and maintenance (OPEX + MAEX) waste disposal (not considered) Costs CAPEX OPEX + MAEX waste disposal used definition for the present analysis : LCC = CAPEX + OPEX + MAEX Time is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 11

Life Cycle Costing Analysis Life Cycle Costing CAPEX OPEX MAEX costs of compressor train energy costs spare parts costs of building costs of personnel costs of personnel costs of connection to electrical grid costs of buildings costs of downtime costs of erection & commissioning costs of emissions costs for getting permissions money interests costs of downtime is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 12

Energy Prices Electricity/Gas price ratio Europe (The ratio decreased during 2008 due to heavy price fluctuations for oil and gas.) 5.00 4.50 Vorteil GT Advantage GT 4.00 Strom-/Gaspreisverhältnis Electricity/Gas price ratio 3.50 3.00 2.50 2.00 1.50 Vorteil EM Advantage EM 1.00 0.50 0.00 Prices from Eurostat, Industry, 2008s1, incl. excise tax, excl. VAT Belgium Bulgaria Germany Estonia EU27 Finland France Great Britain Ireland Italy Latvia Lithuania The Netherlands Poland Portugal Romania Sweden Slovakia Slovenia Spain Czech Republic Hungary is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 13

Case Study: Input data Life Cycle Costing - Analysis Gas storage Compressor String Concept GT - Gear - TC LS EM - Gear - TC HOFIM Distance to network plane 6 [km] Redundancy Concept (N+R) 1+1 Country Great Britain Storage Type *) AGV *) Depleted Gas Field 0 [Nm 3 ] Injection rate 80'000 [Nm 3 /h] Withdrawal rate 80'000 [Nm 3 /h] Show total efficiency 1 2 Calculate LCCs Program version 3.2 dated 2009-06-10 Yearly start/stop frequency of the compressor facility [-] 50 Electricity price (industry, 2008S01, excl. VAT) [ /kwh] 0.08530 Gas price (industry, 2008S01, excl. VAT) Installed Power Technical availability of a string Availability according to redundancy concept Total efficiency of the compressor station [ /kwh] [kw] [%] [%] [%] 0.026 6'000 95.0 99.750 27.9 6'000 98.0 99.960 72.5 6'000 98.5 99.978 71.2 Yearly electricity price increase [%] 3.50 Yearly gas price increase [%] 4.50 Operating hours per operating year Operating years [h] [a] 3'000 20 TOTAL CAPEX before operations begin (incl. N+R) TOTAL OPEX after utilisation period (incl. N+R) TOTAL MAEX after utilisation begin (incl. N+R) [ ] [ ] [ ] 20'699'357 64'418'993 7'212'130 19'834'143 67'414'596 4'491'682 20'942'429 65'989'210 1'380'913 *) only for informative purposes, do not affect the LCC TOTAL LCCs after utilisation period [ ] 92'330'480 91'740'421 88'312'551 is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 14

Results on case study LCCs are mainly defined through OPEX Life Cycle Costs (GT - TC) MAEX Life Cycle Costs (HOFIM) MAEX CAPEX CAPEX OPEX OPEX is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 15

Case study: Great Britain Abgrenzungsanalyse für Gasspeicher Anwendungen Amortisation analysis for a gas storage application Grossbritannien Great Britain 2'000'000 jährliche kummulierte Differenzen bezogen auf CAPEX [ ] yearly cumulative difference in relation to CAPEX [ ] 1'000'000 0-1'000'000-2'000'000-3'000'000-1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 HOFIM minus GT-Gear-TC HOFIM minus EM-Gear-TC HOFIM minus HOFIM -4'000'000 wirtschaftlicher Nutzungszeitraum in Jahren commercial usage period in years is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 16

Expected additional emmission costs Cost of Emissions Beside CO 2, other greenhouse gases are involved (CH 4, N 2, HFCs, SF 6 ) Greenhouse effect of methane is approx. 23 times CO 2 CO 2 trading already common practice Costs of emissions for CH 4 will have to be considered in future (are already considered in several countries) k Methan CO2 23 23 Carbix t is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 17

Conclusion Electric Compression is of advantage when.. a secure and economic source of electric power is available near the compressor station capital investment should be as low as possible high humidity and ambient temperatures requires derating of the gas turbine the electric price/gas price ratio is reasonable low-cost night-time energy available for pipeline/storage puffer operation environmental restrictions apply (gaseous and noise emission limits, architectural restrictions) varying fuel gas qualities or limited transmission capacity in the pipeline exists high operating flexibility is required (starting frequency, frequent load cycles, and wide speed range) high starting and operating reliability/availability is required low operation costs / unmanned operation is required is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 18

Conclusion A general statement cannot be made, because too many project-dependent variables will influence the result. A detailed LCC cost analysis has to be made for each project individually. A decision from CAPEX perspective for fuel or electric driven equipment is generally based on the availability of electric power on site, or the cost to bring the power to site. If electric power is available at site, the decision going with fuel/electric driven trains is generally OPEX driven (fuel/electric costs) Final decision for electric compression or for gas engine driven compresion can only made after considering all project related costs over the life time of the project. FLEXIBILITY and unknown upcoming future EMMISSION REGULATIONS are the keywords in today s changing gas storage and gas transport business. Electric Compression is preferred to cope with these uncertainties. is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited. MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 19

Thank you for your attention. matthias.grapow@man.eu MAN Turbo AG Schweiz mg, OS21 Electric Compression Economics August 27, 2009 20