The Potential of Integrating Wind Power With Offshore Oil and Gas Platforms-2010

7/31/2019 The Potential of Integrating Wind Power With Offshore Oil and Gas Platforms-2010

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The Potential of Integrating Wind Power withOffshore Oil and Gas Platforms

Wei He, Gunnar Jacobsen, Tiit Anderson, Freydar Olsen and Tor D. HansonStatoil ASA, Bergen, Norway

Magnus Korps, Trond Toftevaag, Jarle Eek, Kjetil Uhlen and Emil JohanssonSINTEF Energy Research, Norway

Email: [email protected]

WIN D ENGINEERING VOLUME 34, NO. 2, 2010 PP 125137 125

ABSTRACT

Offshore wind technology has developed rapidly and an offshore wind farm has thepotential to power nearby offshore platforms in the future. This paper presents a case studyof integrating a 20 MW wind farm which addressed the theoretical challenges of integrating

large wind turbines into a stand-alone oil and gas platform grid. Firstly, the operationalbenefits of the 20 MW wind power integration were quantitatively assessed with regard to

the fuel gas consumption and CO2 /NOx emissions reduction. Secondly, the electrical gridstability after integration of the 20 MW wind power was tested by nine dynamic simulations

that included: motor starts, loss of one gas turbine, loss of all wind turbines and wind speedfluctuations. Thirdly, the maximum amount of the wind power available for integration was

identified by simulating critical operational conditions and comparing these to the

governing standards. Integration of an offshore wind farm to an oil and gas platform is

theoretically possible, but has not been proven by this study and many other operationaland economic factors should be included in future feasibility studies.

Keywords: Integration of wind power, oil and gas offshore platforms, fuel gas consumption,

CO2/NOx emissions reduction, electrical grid stability, maximum amount of wind powerintegration.

1. INTRODUCTIONIn the last 10 years, offshore wind technology has developed rapidly. In shallow water sites,

fixed-bottom wind turbines are used commercially. In deeper water sites, the floating windturbine concept has started a full-scale trial. A 2.3 MW floating wind turbine has been in

operation in deep water from September 2009 and the real operation results are better than

the expectations based on the model tests [3]. Thus, an offshore wind farm has the potential to

utilize the excellent wind resource nearby offshore platforms in the future. Comparing the

other alternatives to reduce airborne emissions from offshore platforms, integration of the

offshore wind farm does not require significant space and weight increase of the platforms.

Most oil and gas platforms at Norwegian Continental Shelf (NCS) are in the water depth of

hundred meters to several hundreds meters and the distances to the shore are in the range from

several ten kilometres to hundreds kilometres. The wind resource near offshore platforms is

often excellent due to the higher average wind speed and lower turbulence intensity and wind

shear compared to most onshore wind farm sites. The average wind speed is often in the

range of 9 11 m/s near the offshore platforms on NCS.


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An offshore oil and gas platform often consists of many energy consuming facilities

including drilling, accommodation, processing, exporting, and injection. The current energy

consumption at a platform on NCS is often in the range from 10 MW to several hundreds of MW.

The NCS is mature petroleum province and the energy consumption per produced unit willgrow. Global energy resources are becoming less and less accessible. New of fshore oil and gas

platforms will be placed deeper and further out at sea. The energy consumption per produced

unit at such a new platform might be many times higher than the energy consumption at a

current platform on NCS. As stocks of the conventional lighter crudes decline, heavy oil will

becomes an increasingly important energy source. However, there will be higher energy

consumption to recover heavier oil. Offshore platforms are facing increasingly tougher

challenges to operate in an environmentally acceptable manner.

The power supply to a few offshore platforms comes from electrical cable from an onshore

electrical grid or from a nearby platform. However, most platforms generate their own

electrical power by gas turbines. The gas turbines are also used to directly drive compressors

and pumps. These gas turbines generate about 80% of the total CO2 and NOx emissions fromoffshore installations [1].

Norwegian government has applied a CO2 tax over the last decade. The CO2 tax has

encouraged many companies to reduce their CO2 emissions from their platforms. Statoils

Sleipner project successfully injected 1 million tonnes of compressed CO 2 annually since 1996

[2]. However, Sleipner solution needs CO2 capture, injection, storage and monitoring. The CO2capture and injection usually demand new equipment installation or upgrading the existing

facility on platform. Many gas and oil platforms at NCS are at tail production or at the life

extension period. It is generally very difficult to add any new equipment on the existing

platforms due to the space and the weight limitations.

The study results will be an important input into testing the future feasibility of utilizing

wind power as a supplement power source for offshore oil and gas platforms.

2. STUDY OBJECTIVES AND METHODOLOGYThis paper presents the case of connecting four 5 MW wind turbines to a stand-alone offshore

platform electrical grid shown in Figure 1 and aims at following three objectives:

To estimate the long term operation benefits of wind power integration in terms of

fuel savings, and CO2 / NOx emissions reduction.

To determine the electrical grid stability due to the integration of four 5 MW wind

power generator units.

To identify the maximum amount of wind power possible to integrate to the stand-alone electrical grid on the offshore platform.

This paper used the following methods:

The potential fuel gas saving and CO2 / NOx emission reductions due to wind power

integration were analysed using a simulation model. The inputs were a series of

wind speeds and power consumptions on the platform over time. The simulated fuel

gas consumption and CO2 emissions were compared to the real data from an

offshore platform.

The electrical grid stability was analyzed by nine dynamic simulation cases in four

categories: motor starts, loss of production of one gas turbine, loss of production of

all wind turbines and wind power fluctuations. A dynamic simulation model was

developed and implemented in SIMPOW [4]. The simulated frequency and voltage

126 THE POTENTIAL OF INTEGRATING WIN D PO WE R W IT HOFFSHORE OI L A ND GAS PLATFORMS


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variations under both stationary and transient conditions were compared with the

NORSOK standard [5] for power quality requirements on offshore installations.

Three additional simulations were run to determine the maximum amount of wind

power possible to integrate into the platform. The technical limit is defined by the

load level, the NORSOK standard of the frequency and voltage variations, and the

wind-power strategy during platform operations.

3. DESCRIPTION OF THE STAND-ALONE POWER-GENERATION SYSTEMIn this case study the electrical power to the oil and gas platform is initially supplied by two gas

turbines, with a third turbine as a backup. The two gas turbines are of the same type with

23 MW rated capacity. Under normal operating conditions, the two gas turbines share the load

equally. The gas turbines which directly drive the gas compressors are not connected to the

electrical grid and are not included in this case study.

The efficiency curve of the gas turbine is illustrated in Figure 2. The fuel efficiency of the

23 MW gas turbine decreases at low loads and the fuel consumption at idle is about 20% of

the fuel consumption at full power. There is no definitive minimum power requirement for the

turbines, but it is recommended to avoid loading below 45 MW for longer periods due to

increased mechanical wear.The power consumption over the year varies typically between 20 MW and 35 MW. The

consumption is fairly constant, but can change quickly due to different motor start ups and

shut downs. Load measurements during three days, that represent days with low, high and

average consumption, are shown in Figure 3.

This paper evaluates the potential benefits of connecting four offshore wind turbines with

5 MW capacity each to the electrical grid of the oil and gas platform. The three-bladed 5 MW

floating turbine used in this study is based on the Hywind design [3]. The turbine rotor

diameter is 126 meters and the hub height above the water line is 83 meters. Hywind is

designed for water depths ranging from 120 to 700 meters [3].

The wind conditions near the oil platform are at average wind speeds typically in the

range of 1011 m/s at turbine hub height. For the short-term and long-term simulations, a one-

year wind speed measurement with 20 minutes resolution in Figure 5 is used.

WIN D ENGINEERING VOLUME 34, NO. 2, 2010 127

Figure 1: Connection of four 5 MW wind turbines to a stand-alone offshore platform electrical grid.


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0 5 10 15 20 250

5

10

15

20

25

30

35

40

Gas power (MW)

Fuelefficiency(%)

Figure 2: Efficiency curve of the three gas turbines.

0 500 1000 150020

25

30

35

Time (min)

Powerconsumption(MW)

Max

Min

Avg

Figure 3: Power consumption over three representative days.

2000 4000 6000 8000 2000 4000 6000 80000

10

20

30

40

Time (hour)

Windspeed(m/s)

0

1

2

3

4

5

Duration (hours)

Poweroutput(MW)

Figure 4: 20 minutes average wind speed and calculated duration curve for the wind power.


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4. SIMULATIONS OF FUEL SAVING AND CO2 / NOX EMISSION REDUCTIONS4.1. Operation StrategyThe basic operational strategy is that the wind turbines supply the power load. Then there are

two options for running the gas turbines:

Share the remaining load (load wind power) equally.

Allow one of the gas turbines to be shut down. The second gas turbine is shut down

at time step if the following operation conditions is satisfied:

where Pwind (t) is the wind power output at time step t and is the rated power

output of the gas turbine. is a time-series of the forecasted load

from time step tto time step t+tgas,start, where tgas,start is the start up time of the gas turbine.

is a margin that is added to the load in order to account for possible short-term wind

power reduction.

4.2. Three Daily CasesThe power system operation was simulated for the three daily cases and the summary of the

simulation results is presented in this section.

Three daily cases were simulated with and without 20 MW of wind power generation

available. When simulating the case with 20 MW of wind power generation, both the

operational strategies of using both gas turbines together or allowing one stop/start gas

Pwindmargin

P t t t load gas start ( , , ),+

Pgasrated

P t P P t t t wind gas rated

load gas star ( ) max ( , , ,+ > + tt wind margin

gas startP t) , +


50 100 150 200 250 300 3500

10

20

30

0

10

20

30

40

Day of year

50 100 150 200 250 300 350

Day of year

Power

(MW)

Load

Wind

Loa

dwind(MW)

Figure 5: Upper: Time-series for load and wind power from 20 MW capacity. Lower: Net load (loadwindpower). The demand time-series is a combination of the daily averages and the daily minute-data.


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turbine are used. The simulated fuel consumption and CO2 / NOx emissions for the three daily

cases, and the reduction due to the wind power integration are given in Table 1.

Accordingly, the fuel saving and emission reductions from the low, average and high daily

load cases are listed in Table 2.

4.3. Yearly CaseThe yearly case is based on the real load data. A time-series for yearly power demand was

constructed by combining actual measured daily loads for one year and it is shown in Figure 5.

The yearly case was simulated with and without an integrated 20 MW wind power

generator. The simulated fuel consumption and CO2 / NOx emissions for the yearly case and

the reduction due to wind power are given in Table 3. The simulation results show that the

integration of a 20 MW wind farm to an offshore platform would achieve approximately a 40%

reduction in fuel gas and CO2/NOx emissions when one gas turbine can be started and

stopped. The yearly case would result in an annual reduction of 53,790 tonnes of CO 2 and

366 tonnes of NOx.

The simulation results also show that the gas turbine start/stop operating strategy would

result in a further annual reduction of 6 Msm3 of fuel gas, 14,070 tonnes of CO2 and 96 tonnes of

NOx. This further reduction is due to the gas turbine efficiency increase from 25.6% to 30.1%.The penalty is that the second gas turbine must be switched off and started 543 times during

the year, and 1.5 times a day. Further study is needed to assess the possible mechanical

degradation and life-span reduction of the gas turbine due to the additional motor start

and stops.

A simple validation was made in this study. The simulated fuel gas consumption and CO 2emissions were compared with the real fuel gas consumption and the measured CO2emissions from the platform. The simulated fuel gas consumption and CO2 emissions agree

with the real platforms operation data.

4.4. Estimated Future Fuel Gas Saving and Emission ReductionThe estimated fuel gas saving and CO2 / NOx emission reduction from year 2009 to 2020 aregiven in Table 4.


Table 1: The simulated fuel consumption and emissions from the three daily casesReduction Due

Simulation Results to Wind PowerOperation Wind Fuel CO2 NOx Fuel CO2 NOx

Cases Strategy (MW) (ksm3)* (Tonnes) (Tonns) (ksm3) (Tonnes) (Tonns) 0 216 475 3.2

High load Equal load 20 140 307 2.1 76 168 1.1

Start/stop 20 120 264 1.8 96 211 1.4

0 160 353 2.4

Low load Equal load 20 100 220 1.5 60 133 0.9

Start/stop 20 60 133 0.9 100 220 1.5

0 192 423 2.9

Average Equal load 20 117 257 1.8 75 166 1.1

load Start/stop 20 94 208 1.4 98 215 1.5* Volume at standard condition: 1 atmosphere and 15C.

Table 2: The fuel gas saving and emissions reduction from the three daily casesFuel Gas Saving, ksm3/Day CO2 Reduction, Tonnes/Day NOx Reduction, Tonnes/Day60 100 133 220 0.9 1.5


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Table 4 shows that the estimated average CO2 emission reduction annually is 55.6 ktonnes.

In order to reach 1 million CO2 emission reduction annually, 80 units of 5 MW wind turbines

must be deployed near the selected platform. Comparing with the Sleipner project of 1 million

CO2 injection annually, it results in NOx emission reductions as well.

4.5. Two Proposed Future Steps to Increase Wind Power CapacityThe wind power capacity can be increased significantly with some additional actions. Two

proposed steps to increase wind power load are as follows.

The platform is connected to three nearby platforms by an electrical sub-sea cable.

The direct gas turbine driven compressors are replaced by electrical motors.

In the first scenario, by connecting the study platform to three nearby platforms via subsea cables, it would be possible to increase the wind power capacity to at least 85 MW, using a

conservative approach to determine the maximum possible amount of wind power

generation. This could potentially lead to yearly CO2 reduction of 160000 tonnes and NOxreduction of 1200 tonnes.

In the secondly scenario, when the direct driven gas turbines are replaced by electrical

motors, the electrical load on the platform will increase and more wind power could be

integrated to the platform.

Electricity storage has not been studied here. The first reason is that most oil and gas

platforms usually have a lot of spare power generation capacity. Typically the electricity

load is half of the power generation capacity. The second reason is that most platforms have

no possibility to add electricity storage equipment due to the space and weight limitation ofthe platform.


Table 3: The simulated fuel consumption and emissions from the yearly caseReduction Due

Simulation Results to Wind PowerOperation Wind Fuel CO2 NOx Fuel CO2 NOx

Cases Strategy (MW) (Msm3) (Tonnes) (Tonns) (Msm3) (Tonnes) (Tonns) 0 61 134100 914

Load: Equal load 20 43 94380 644 18 39720 270

30.6 MW Start/stop 20 37 80310 548 24 53790 366

Table 4: Estimated future gas saving and CO2 / NOx emission reductionFuel Saving CO2 Reduction NOx Reduction

Year Mill. Sm3 K Tonnes Tonnes2009 24.2 53.3 363.3

2010 24.5 53.8 367.0

2011 24.7 54.4 370.6

2012 25.9 54.8 373.92013 25.1 55.3 377.1

2014 26.5 58.4 398.2

2015 26.3 57.9 394.8

2016 26.1 57.3 390.9

2017 25.8 56.7 386.8

2018 25.4 56.0 381.5

2019 25.1 55.2 376.6

2020 24.7 54.4 370.6

Average 25.3 55.6 379.3


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5. ELECTRICAL GRID STABILITY SIMULATIONS5.1. Dynamic CasesThe second objective of this paper is to study the dynamic impact of integrating 20 MW of

wind power into the electrical power system. A dynamic simulation model was developed andimplemented in SIMPOW [4]. The wind turbines are to be installed via cables, transformers

and converters to the electrical grid on the platform. All cables and lines for the electrical

installation are modelled as impedances. The cables for the wind turbine installation are

implemented as PI-equivalents. The model of wind energy conversion unit in SIMPOW

includes the following properties as shown in Figure 6:

A turbine aerodynamic nonlinear model based on power-coefficient characteristic

curves, with the speed governed by the pitch angel control of the rotor blades.

A synchronous generator with a full power converter interface to the grid.

The electrical grid stability was evaluated as to whether the system was destabilised after

a set of worst-case disturbances, to see if the voltage and frequency variations where withinacceptable limits. In this paper, NORSOK standard is applied.

The disturbances defined in this study are:

Motor starts

Loss of production of one gas turbine

Loss of production of all wind turbines

Wind power fluctuations

The nine selected dynamic cases are listed in Table 5.

5.2. Simulation ResultsThe section gives the frequency and voltage variations for the nine simulation cases. The loadscenario of 35 MW was simulated and the simulated frequency and voltage variations under

both stationary and transient conditions are compared to NORSOK standard.


Synchronous machine

Statorpower

converter

Gear

Control

Figure 6: Wind turbine unit in SIMPOW simulation model.


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Table 5: Nine dynamic simulation casesDisturbances Operation Modes

A: Online start of one large induction motor A1: 1 gas turbine

A2: 1 gas turbine + 2 wind turbine: 10 MW

B: Loss of one gas turbine production B1: 2 gas turbine + 2 wind turbine: 10 MWB2: 2 gas turbine + 4 wind turbine: 20 MW

C: Loss of all wind turbines C1: 1 gas turbine + 2 wind turbine: 10 MW

C2: 2 gas turbine + 4 wind turbine: 10 MW

C3: 2 gas turbine + 4 wind turbine: 10 MW

D: Wind fluctuations A2: 1 gas turbine + 4 wind turbine: 10 MW

A2: 2 gas turbine + 4 wind turbine: 10 MW

The simulation results in Figures 7 and 8 can be listed as follows.

The motor start resulted in a frequency variation of +0.5% to 1.5% and the voltage

variation was +13% to 18%. The added wind power improves the transient

performance of the system. The main reason is that the connected conventional

generator is de-loaded by the amount of wind power produced.

The loss of one gas turbine resulted in a frequency variation of 3% with the final

deviation of 1% and the voltage variation was 4% with a final deviation of 0.5%.

The loss of all wind turbine power resulted in a frequency variation of7.3% and the

voltage variation was 1.7% to 5.3% under transient conditions.

0 10 20 30 40 50 600.9

0.92

0.94

0.96

0.98

1

1.02

Time [s]

Frequency[p.u.]

Case A1

Case A2

0 10 20 30 40 50 600.9

0.92

0.94

0.96

0.98

1

1.02

Time [s]

Frequency[p.u.]

Case B1

Case B2

0 5 10 15 20 25 300.9

0.92

0.94

0.96

0.98

1

1.02

Time [s]

Frequency[p.u.]

Case C1

Case C2

Case C3

500 150100 2000.9

0.92

0.94

0.96

0.98

1

1.02

Time [s]

Frequency[p.u.]

Case D1

Case D2

Figure 7: Frequency variations under transient conditions for the 9 simulation cases.


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Table 6: The largest deviations of frequency and voltage ( f and V) in nine simulation casesCase A1: Direct online start of large motor f= 5.1%, V = 18%Case C3: Loss of all wind turbines f= 7.3%, V = 2%

Table 7: The largest of frequency and voltage deviations ( f and V) during

loss of all wind turbinesC1: 1 gas turbine + 2 wind turbine: 10MW, load: 19 MW f= 4.5 %, V = 1.5%C2: 2 gas turbine + 4 wind turbine: 20MW, load: 35 MW f= 4.6 %, V = 1.5%C1: 1 gas turbine + 4 wind turbine: 20MW, load: 25 MW f= 7.3%*, V = 1.7%

*NORSOK frequency transient requirement: 5%.

The wind fluctuations resulted in frequency variation of 1% and voltage variations of

0.05%. Thus, the variations of voltage and frequency due to wind fluctuations are much

smaller than the three worse-case scenarios above.

The largest deviations in frequency and voltage are observed in Cases A1 and C3 listed

in Table 6.

In Case A1, the added wind power improved the transient performance. In Case C3, the loss

of all wind turbines became critical when the amount of wind power integration is increased.

The frequency and voltage deviations during loss of all wind turbines are given in Table 7. This

worst-case scenario will be used to identify the maximum amount of wind power available forintegration to the stand-alone electrical grid on the offshore platform in the following section.

5 10 15 20 25 300.8

0.85

0.9

0.95

11.05

1.1

1.15

Time [s]

Voltage[p.u.]

Case A1

Case A2

5 10 15 20 25 300.8

0.85

0.9

0.95

11.05

1.1

1.15

Time [s]

Voltage[p.u.]

Case B1

Case B2

5 10 15 20 25 300.8

0.85

0.9

0.95

1

1.05

1.1

1.15

Time [s]

Voltage[p.u.]

Case C1

Case C2

Case C3

50 1500 100 2000.8

0.85

0.9

0.95

1

1.05

1.1

1.15

Time [s]

Voltage[p.u.]

Case D1

Case D2

Figure 8: Voltage variations under transient conditions for the 9 simulation cases.


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5. IDENTIFYING THE MAXIMUM AMOUNT OF WIND POWER FOR INTEGRATIONThe crucial factors determining maximum wind power load for integration include the

following factors.

Electrical grid characteristics include both grid structure and the equipment powergeneration characteristics.

Load level.

Operation requirements. In this study, both user defined requirements and NORSOK

standard with regard to the frequency and voltage variations are considered.

Power generation strategy.

Economic feasibility.

In this section, the maximum wind power during loss of all wind power was quantitatively

assessed with regard to NORSOK standard of frequency and voltage variations.

When the load is 35 MW, two gas turbines should be in operation and the maximum windpower able to be integrated is estimated to be between 20 MW to 25 MW in order to remain

within the frequency and the voltage variation of the NORSOK standard and to be able to

cope with the loss of all wind power.

When the load is 19 MW, one gas turbine should be in operation and the maximum amount

of wind power able to be integrated is estimated to be between 20 MW to 25 MW in order to


Table 8: Case N1 to determine the potential maximum wind powerLoad Operation Mode Results Limits of Wind Power

Case N1: Case N1: 2 gas turbines at Frequency & voltage < 35 MW

35 MW zero power output. variations>

NORSOK35 MW wind power specification

0 10 20 30 40 500.9

0.92

0.94

0.96

0.98

1

1.02

Case N1

Time [s]

0 10 20 30 40 50

Time [s]

Frequency[p.u.]

Voltage[p.u.]

0.8

0.85

0.9

0.95

1

1.05

1.1

1.15Case N1

Figure 9: Frequency and voltage variations in Case N1.

Table 9: Cases to determine the potential maximum wind power at load 35 MWLimits of

Load Operation Mode Results Wind Power35 MW Case N2: 2 GT in operation Frequency & voltage variations

25 MW wind power>

NORSOK specification 20 MW


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remain within the frequency and the voltage variation of the NORSOK standards and be ableto cope with the loss of all wind power.

In conclusion, the simulation cases showed that maximum amount of wind power able to

be integrated into the platform is very sensitive to the power generation strategy. When the

base load is 35 MW, two gas turbines should be in operation and the estimated maximum

amount of wind power able to be integrated is between 20 MW to 25 MW in order to remain

within the frequency and the voltage variation of the NORSOK standard and able to cope with

the loss of all wind power. When the load is 19 MW, only one gas turbine should be in operation

and the estimated maximum amount of wind power able to be integrated into the platform

would be between 10 MW to 15 MW.

Note that the power generation strategy to stop one gas turbine in order to achieve the

maximum fuel saving and CO2 / NOx emission reduction conflicts with the strategy to havetwo gas turbines in operation in order to achieve electrical grid stability.


0 10 20 30 40 500.9

0.92

0.94

0.96

0.98

1

1.02Case N2

Time [s]

0 10 20 30 40 50

Time [s]

Frequency[p.u.]

Voltage[p.u

.]

0.8

0.85

0.9

0.95

1

1.05

1.1

1.15Case N2


Table 10: Cases to determine the potential maximum wind power at load 19 MWLoad Operation Mode Results Limits of Wind Power

19 MW Case N3: 1 GT in operation F & V > NORSOK < 15 MW15 MW wind power requirements

19 MW Case C1: 1 GT in operation F & V < NORSOK > 10 MW10 MW wind power requirements

0 10 20 30 40 500.9

0.92

0.94

0.96

0.98

1

1.02Case N3

Time [s]

0 10 20 30 40 50

Time [s]

Frequency[p

.u.]

Voltage[p.u

.]

0.8

0.85

0.9

0.95

1

1.05

1.1

1.15Case N3



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6. CONCLUSIONSThere is abundant local wind power near the real offshore platform that this paper used as a

case study. This study simulated that a 20 MW wind capacity operating in parallel with three

gas turbines at an operating platform would result in significant fuel gas consumption andCO2 / NOx emission reductions, especially when allowing for intermittent operation of the gas

turbines. The wind power capacity could be further increased with two proposed future

scenarios: firstly, the platform could be connected to three nearby platforms by an electrical

sub-sea cable, and secondly the gas turbine driven compressors could be replaced by

electrical motors.

The electrical grid stability after integration of a 20 MW wind power generator was tested

by nine dynamic simulations including four disturbances; 1) motor starts; 2) loss of one gas

turbine; 3) loss of all wind turbines and 4) wind speed fluctuations. The variations of frequency

and voltage due to wind fluctuations are much smaller than the first three disturbances. The

added wind power reduces the voltage and frequency variations during a motor start. The

loss of all wind power became critical when the amount of wind power integration is increasedand this scenario was used to identify the maximum amount for the wind power able to be

integrated to the stand-alone electrical grid at the offshore platform.

Finally, this study is only a theoretical case study and has not demonstrated the feasibility

of integrating wind power into an offshore platform. Further operational and economic work

is needed to design a workable technical solution to integrate a wind power farm to an

offshore platform. Future feasibility studies must consider more than just the voltage and

frequency variations.

ACKNOWLEDGEMENTSThe authors gratefully acknowledge Statoils new idea and offshore wind programs. The

authors thank Finn G. Nielsen and Jim Daniels for suggestions to this paper.

REFERENCES1. OLF, Offshoe renewable power for O & G Installation, feasibility study, October 2005.

2. StatoilHydro, R&D project CO2 value chain, Carbone Dioxide, Capture, transport and

storage.

3. StatoilHydro, Hywind by StatoilHydro, The worlds firs full scale floating wind turbine,

Printed June 2009.

4. SINTEF, SIMPOW program manual, 2006.

5. NORSOK Standard E-001, electrical systems, Edition 5th

, July 2007.6. OLF, The Norwegian oil industry association, 2007 Environmental Report, 2007.



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The Potential of Integrating Wind Power With Offshore Oil and Gas Platforms-2010