research article economic efficiency assessment of ...(wind/diesel/hydrogen systems). dump load load...

Hindawi Publishing CorporationJournal of Renewable EnergyVolume 2013 Article ID 101972 10 pageshttpdxdoiorg1011552013101972

Research ArticleEconomic Efficiency Assessment of AutonomousWindDieselHydrogen Systems in Russia

O V Marchenko and S V Solomin

Energy Systems Institute of Russian Academy of Sciences 130 Lermontov Street Irkutsk 664033 Russia

Correspondence should be addressed to O V Marchenko marchenkoisemseiirkru

Received 19 December 2012 Accepted 13 March 2013

Academic Editor Onder Ozgener

Copyright copy 2013 O V Marchenko and S V Solomin This is an open access article distributed under the Creative CommonsAttribution License which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

The economic efficiency of harnessing wind energy in the autonomous power systems of Russia is analyzed Wind turbines areshown to be competitive for many considered variants (groups of consumers placement areas and climatic and meteorologicalconditions) The authors study the possibility of storing energy in the form of hydrogen in the autonomous winddieselhydrogenpower systems that include wind turbines diesel generator electrolyzer hydrogen tank and fuel cellsThe paper presents the zonesof economic efficiency of the system (set of parameters that provide its competitiveness) depending on load fuel price and long-term average annual wind speed At low wind speed and low price of fuel it is reasonable to use only diesel generator to supplypower to consumers When the fuel price and wind speed increase first it becomes more economical to use a wind-diesel systemand then wind turbines with a hydrogen system In the latter case according to the optimization results diesel generator is excludedfrom the system

1 Introduction

In the recent years the energy policy of many countrieshas been aimed at increasing the share of renewable energysources (RES) in the total energy production In Russiathe share of RES (without large hydropower plants) inthe electricity production does not exceed 1 Howeverthe ldquoEnergy Strategy of Russia for the period up to 2030rdquo(approved by the Russian Government) suggests that in 20years this share may increase up to 45

Providing a substantial environmental effect (decrease inthe emissions from energy sector) RES can often be eco-nomically efficient and competitive with the energy sourcesbased on fossil fuel [1ndash7] It is expected that in the nearestand moreover distant future the role of RES in Russian andworld energy industry will essentially increase due to theimprovement of characteristics and a projected rise in thefossil fuel price [8ndash12]

It is reasonable to use RES primarily in small autonomous(decentralized) power systems located in remote hard-to-reach areas where the price of imported fossil fuel is veryhigh Russian zones of decentralized power supply that do not

have anymodern electrical networks and large energy sourcesoccupy about 70 of the country and are situated mostly inthe Far North The Far North is represented by a numberof regions in the European part of the country (Murmanskand Arkhangelsk regions the Republic of Karelia and theRepublic of Komi) Siberia (the north of Tyumen Region andKrasnoyarsk Territory) and the Far East (Yakutia ChukotkaMagadan Kamchatka and Sakhalin regions) These territo-ries have significant reserves of gold platinum diamonds tinlead and other mineral resources

In total about 1400 small settlements with a population ofapproximately 20 million people are located in decentralizedpower supply zones of Russia [3 4] About 7 thousand dieselpower plants operate here The majority of them have a highdegree of physical deterioration and low efficiencyThe cost ofelectricity produced by new diesel generators usually exceeds25ndash30 centkWh (US dollar for economic assessment is usedthroughout the paper) and in the remotest regions with olddiesel generators it exceeds 50ndash70 centkWh

Decentralized systems of power supply are characterizedby the following features

2 Journal of Renewable Energy

(i) settlements are spread throughout large scarcely pop-ulated territories

(ii) electric load of consumers in each settlement does notexceed 1ndash3MW

(iii) transport infrastructure is underdeveloped

(iv) the main electricity source is diesel power plants

(v) diesel power plants use expensive diesel fuel whichusually costs more than $800ndash$1000toe [4]

Therefore the introduction of renewables to increase thecost effectiveness of power supply is an urgent problem forthese systems One of the most effective types of RES is windturbines [1 4]

In 2011 the total installed capacity of all wind turbinesoperating in the world accounted for 238GW (increasedby 20 as compared to 2010) [13] Wind turbines generateabout 25 of the total electricity production in the world Asopposed to both many developed and developing countriesRussia uses wind energy very little The installed capacity ofwind turbines is about 20MW and the rate of wind energydevelopment was less than 10 in 2010 and 2011 [14] Theshare of wind turbines in the total electricity production inRussia is negligible (less than 001)

Meanwhile the potential for the wind energy develop-ment in Russia is really great Russia has the longest shorelinein theworld abundant treeless flatlands and largewater areasof inner rivers lakes and seas which represent the mostfavorable sites for wind turbines

The main advantages of wind turbines are as follows

(i) no harmful emissions in the process of electricityproduction

(ii) relative cheapness of generated electricity (3ndash5 centkWh for the best turbines under good windconditions)

(iii) possibility of significantly saving on fossil fuel in thecourse of operation in an autonomous power system

At the same time wind turbines have a flaw This isan unsteady electricity generation (depending on changesin wind speed) Therefore wind turbines are used incombination with energy sources that operate under thecontrolled conditions and supply power to the load whenpower generated by wind turbines is insufficient or duringtheir downtime Besides power systems with wind turbinesinclude energy storage devices

The research aims to study the economic efficiencyof harnessing wind energy in Russia for a wide range ofparameters (fossil fuel price climatic and meteorologicalconditions power and load curve of consumers and cur-rent and prospective technical and economic indices ofthe power system components) First of all the authorsconsider the most promising winddiesel systems includingthe systems that produce store and use hydrogen in fuel cells(winddieselhydrogen systems)

Dumpload

Load

Windturbine

Diesel

simsim

Figure 1 Winddiesel system

2 Variants of Harnessing Wind Energy

The authors consider three variants of harnessing windenergy in the autonomous power systems to supply power toconsumers

In the first variant wind turbines are included in thewinddiesel system (Figure 1) The capacity of a diesel gener-ator is chosen so that it provides uninterrupted power supplyto consumers even in the case of wind turbine downtimeduring calms In the periods of strong wind however someamount of power generated from wind turbines turns out tobe redundant and is diverted to the dump load

The other two variants allow for the storage of energy inthe form of hydrogen produced by electrolysis and electro-chemically transformed into electric energy Under certainconditions the introduction of a subsystem for productionstorage and use of hydrogen for energy purposes into thewinddiesel system can decrease the diesel fuel consumption(or even exclude the diesel generator from the system) andreduce the costs of electricity production

The second variant considers a simplified (linear) schemein which electric energy or hydrogen sequentially passesthrough the system components diesel generator is excluded(Figure 2) Here it is assumed that the volume of hydrogenproduced is sufficient to have constant electric power offuel cells This means that the combination of wind turbineswith stochastic power generation and a hydrogen system(electrolyzer hydrogen tank and fuel cells) allows us toobtain a new property of the energy source that is constantgeneration (by additional costs) If the installed capacity ofan electrolyzer is lower than the capacity of wind turbinessome amount of the generated electricity may turn out tobe redundant and will be diverted to the dump load Theuse of excess electricity in heat supply (as well as the heatgenerated by fuel cells) was not considered in this paper Infact the utilization of this heat can prove to be economicaland increase the efficiency of the whole system [1] Howeverthis will require the introduction of additional componentsinto the scheme (heat exchangers pipelines pumps etc) andmore detailed consideration of consumer specific featureswhich goes beyond the scope of this paper

In the third variant (Figure 3) the autonomous powersystem includes diesel units one or several wind turbineselectrolyzer hydrogen tank fuel cells and electricity con-sumers with their load curve It is assumed that the diesel

Journal of Renewable Energy 3

Windturbine

Dumpload

Load

Fuelcells

Hydrogen tankElectrolyzer

simsim

==

Figure 2 Windhydrogen system

Windturbine

Hydrogentank Electrolyzer

Fuel cell

Diesel

Load

Dumploadsim

simsim

sim

=

=

Figure 3 Winddieselhydrogen system

power plant wind turbines electrolyzer and fuel cells areprovided with all the devices required to control the networkWind turbines supply electricity directly to the consumerswith changing load If this electricity is insufficient dieselgenerator and fuel cells can operate simultaneously Theexcess power from wind turbines is consumed by the elec-trolyzer (if the hydrogen tank is not fully filledwith hydrogen)or absorbed by the dump load

3 Calculation Method

As is known [8] the cost effectiveness of an investmentproject is characterized by the net present value (NPV) thatis the total income obtained during the project period 119879

reduced to the initial time point

NPV = int

119879

0

119864 (120591) exp (minus120590120591) 119889120591 (1)

where 119864(120591) is the cash flow 120590 = ln(1 + 119889) 119889 is the annualdiscount rate

For many energy sources including RES we can usethe following simplified model which describes their con-struction and operation construction takes a short time andrequires capital investments 119870 Right after the constructionthe energy source starts to operate under nominal conditionswith average annual costs 119885 and electricity supply 119876 at price119901

Then

NPV = minus119870 + int

119879

0

(119901119890119876 minus 119885) exp (minus120590120591) 119889120591

=1

120590[1 minus exp (minus120590119879)] (119901119890119876 minus 119885) minus 119870

(2)

where 119901119890is the electricity price

Among the compared alternative variants the best onewill provide the maximum NPV

Costs 119885 can be divided into two parts constant com-ponents (that do not depend on the volume of electricityproduction) and variable components that consist mainly offuel costs

119885 = 120583119870 + 119901119891119887119876 (3)

where 120583 is the specific constant costs (share of investments)119901119891is the fuel price 119887 is the specific fuel consumption (a value

inversely proportional to the efficiency)Then from (1)ndash(3) we obtain

NPV =1

120590[1 minus exp (minus120590119879)]119876 (119901

119890minus 119878) (4)

where

119878 =CRF sdot 119870 + 119885

119876=119896

ℎCRF + 119896

ℎ120583 +

119901119891

120579 sdot 120578(5)

is the electricity cost Here we use the following notations 119896is the specific capital investments (per power unit) ℎ = CFsdot119867is the annual number of utilization hours (CF is the capacityfactor 119867 = 8760 hyear) CRF = 120590[1 minus exp(minus120590119879)] is thecapital recovery factor 120579 = 116 sdot 10

3 kWhtoe is the energyequivalent

According to (4) the electricity cost represents the mini-mum price at which the project is cost effective (net presentvalue equals zero) and the best variant (NPV = max) shouldbe chosen on the basis of the criterion ofminimum electricitycost (5)

The terms in the right-hand side of equality (5) representthe capital OampM and fuel components of the electricitycost respectively Fuel price for the energy sources based onenergy of the wind sun or rivers equals zero (119901

119891= 0)

while the value of capacity factor CF significantly depends onmeteorological conditions [1 3 4 15 16]

To assess the competitiveness of RES we should comparethe cost of energy produced on their basis with the cost ofenergy from competing energy sources In the case whereRES operate under uncontrolled (stochastic) conditions andrequire full capacity backup the cost of energy produced bythem should be compared not to the total cost but to the


fuel component of the cost of energy produced by the energysource on fossil fuel [3 4]

This comparison makes it possible to assess the com-petitiveness of RES (Figure 1) at the first approximation andexclude inefficient variants from further consideration Byanalogy we canmake preliminary estimation of the hydrogenand electricity cost (Figure 2) that can be compared to thecost of diesel fuel and electricity from diesel generator Suchestimation proves to be very illustrative and narrows thefeasibility region of parameters to be used in calculationsfor the autonomous power system taking into account theinteraction between its components

More accurate calculations require that the system effectsrelated to power flows between system components and itsstorage have to be taken into account Optimization of theautonomous power system structure and operation (Figure 3)is reduced to solving the problem find the objective function(electricity cost) minimum

119878 =1

119876[sum

119894

CRF119894119870119894+ 119885119894] 997888rarr min (6)

subject to

119875DG (119905) + 119875WT (119905) + 119875FC (119905) = 119871 (119905) + 119880 (119905) (7)

0 le 119875119894 (119905) le 119875

119894max (8)

119880 (119905) ge 0 (9)

119875WT (119905) = 119875WT max119891 (V) (10)

119875FC (119905) le119875lowast

HT (119905) 120578HT120578FC

Δ119905 (11)

119875EL (119905) = min(119880 (119905) (119875lowast

HT max minus 119875lowast

HT (119905)

(120578ELΔ119905))) (12)

119875lowast

HT (119905) = 119875lowast

HT (119905 minus Δ119905) + [119875EL (119905) 120578EL minus119875FC (119905)

(120578FC120578HT)]Δ119905

(13)

The following notation is used 119875 is the power of energysource 119875lowast is the energy equivalent of hydrogen in hydrogentank 119905 is the time 119871 is the load 119880 is the power surplus 119891(V)is the wind turbine power curve Δ119905 is the time step indices119894 is the type of energy source (DG is the diesel generatorWT is the wind turbine EL is the electrolyzer HT is thehydrogen tank and FC are the fuel cells) max and min arethe maximum and minimum values

Equation (7) is the power balance at the time point 119905 (8)is the power constraints (9) is the condition of shortage-freepower supply (10) is the dependence of wind turbine poweron wind speed (random value) (11) is the constraint on thepower of fuel cells with respect to hydrogen reserve (12) is theconstraint on the power of electrolyzer with respect to powersurplus and available capacity in the hydrogen tank (13) is thehydrogen balance in the hydrogen tank

To solve system (6)ndash(13) the algorithm described in [7]was used Continuous time functions were replaced with sets

of discrete values with the step of 1 hour Wind speed wasmodeled in the form of random processes in terms of thealternating periods of low and high wind speeds This isessential for the systems with energy storage systems andin this case for the determination of optimal capacity of thehydrogen tank

At the first stage when the installed capacities of energysources and the hydrogen tank capacity are given the operat-ing conditions are optimized at each time point in accordancewith the criterion of minimum fuel costs The electric load(7) is first covered by energy from wind turbines then by theenergy stored in the hydrogen tank and finally by the energyfrom diesel generator The excess energy from wind turbinesis sent to electrolyzer for the production of hydrogen

At the second stage after the calculation of operatingconditions on the entire time interval from 119905 = 0 to 119905 = 119879the installed capacities of energy sources and the hydrogentank capacity are optimized according to criterion (6) subjectto constraints (8) and (9)

4 Initial Data

The factors that determine the economic efficiency of usingwind turbines and hydrogen system in addition to the dieselpower plant (or instead of it) in the autonomous powersystems are

(i) wind speed(ii) diesel fuel price(iii) maximum power and degree of load unevenness(iv) technical and economic indices of power plants

The most important energy characteristic of the windis its long-term average annual speed 119881 measured at aheight of a weather vane (about 10m) Figure 4 presentsthe distribution of this characteristic across the territory ofRussia The zones of low (up to 4ms) medium (4ndash6ms)and high (more than 6ms) wind speeds are highlightedAverage wind speed reaches its maximum on the seacoastsand decreases in the continental areas

In the European part of the country annual averagewind speed is 2ndash4ms and on the coasts of the ArcticOcean and the Baltic Sea and in some regions of the NorthCaucasus and Volga region it reaches 5ndash6ms The highestwind speed (more than 7ms) is typical of the coastal areas inArkhangelsk and Murmansk regions

In the Asian part of the country the zone of light wind(less than 2-3ms) covers large territories of the continentalareas of Siberia and the Far East Higher wind speed (4-5ms)is characteristic of some mountainous areas coast of LakeBaikal and valleys of large Siberian rivers (the Ob YeniseiAngara and Lena) The highest long-term average annualwind speed (above 6ndash8ms) is in the coastal areas of Tyumenregion Krasnoyarsk Territory Magadan region ChukotkaKamchatka Sakhalin and islands in the Arctic and PacificOceans

In this study the calculations weremade for average windspeeds equal to 4ndash8ms which corresponds to a range of


Pacific Ocean

Arctic Ocean

4ndash6mslt4ms gt6ms

Figure 4 Long-term average annual wind speed119881 (ms) at a heightof 10m on the territory of Russia

wind conditions from ldquobadrdquo to ldquovery goodrdquo Wind speed isdistributed according to theWeibull distributionwith a shapeparameter 120572 = 15 [1]

The relationship between wind speed and the heightwas described by a logarithmic dependence with a surfaceroughness degree 119911

0= 003m [1] The operating character-

istic of wind turbines (power versus wind speed) is takenin accordance with the installation data of the companyldquoFuhrlanderrdquo the height of a wind turbine tower for the loadof 50 kW is 20m and for the load of 1000 kW is 40m

A retrospective analysis shows that in the last 10ndash15years the price of diesel fuel has increased 2-3 times Todaythe minimum wholesale price of diesel fuel is in the NorthCaucasus ($780toe) and the maximum is in the Republicof Yakutia ($1600toe) For the southern and central regionsof the European part of Russia the typical prices are $800ndash$1000toe and for the northwest regions of the EuropeanRussia and northeast regions of the Far East they equal$1100ndash$1500toe

In the calculations the diesel fuel price in the range$800ndash$1500toe was considered which corresponds to theconditions from ldquorelatively cheaprdquo to ldquomoderately expensiverdquodiesel fuel for the autonomous power systems

Themajority of decentralized electricity consumers live inrural and urban settlements with the population from 50 to5000 people We consider the following consumers (1) time-constant power of 50 or 1000 kW (for the schemes in Figures1 and 2) (2) small consumers with a variable electric load upto 50 kW (3) larger consumers with a load up to 1000 kW (forthe scheme in Figure 3)

In the latter two cases the load power was assumed to benormally distributedThe parameters of the normal law werechosen by the approximation of the annual load curve for aload of 50 kW (maximum value) the average power is 20 kWand the standard deviation is 5 kW for the load of 1000 kW685 kW and 100 kW respectively

Power of the wind turbine backup energy source (dieselor fuel cells) was chosen according to the condition of powersupply to consumers under any wind conditions This allows

us not to include losses from power undersupply whosenumerical value is characterized by significant uncertaintyin the objective function To take into account the startupinertia of diesel generator and undesirable sharp change inits operation the diesel generator was assumed to operateconstantly (minimumpower is 30 of the installed capacity)Fuel cells work at stationary (Figure 2) or near stationaryregimes (Figure 3) because of the hydrogen store presence

The main technical and economic indices of the powersystem componentswhich determine the economic efficiencyof the considered power supply schemes are the specificcapital investments fixed operating costs efficiency andlifetime

Table 1 shows the corresponding indices for two powerlevels (50 kW and 1000 kW) and two time points that isthe current indices (equipment is available in the market)and prospective indices The value of power consumed (50or 1000 kW) influences technical and economic indices ofthe used equipment and the degree of load unevennessinfluences the optimal relationship between the installedcapacities as well as the operating conditions of the energysources

These variants are formed on the basis of the studiespresented in [3 4 17ndash24] Current indices are taken fromthe price lists of Russian manufacturers of equipment (withrubles converted to dollars) Among the available forecastsof changes in the indices over time we have chosen theldquomoderately optimisticrdquo ones (the most probable from theauthorsrsquo viewpoint)

The main problems of hydrogen energy are the high costof equipment and the complexity of storing and transportinghydrogen in both gas and liquid form Hydrogen productionby electrolysis on the basis of ldquoexcessrdquo power produced bywind turbines right in the place of consumption makesthis process cheaper and obviates the need to transporthydrogen Further technological development and increasein hydrogen production and utilization will considerablyimprove the economic characteristics of the basic hydrogensystem components that is electrolyzers and fuel cells [17ndash24]

Investment in wind turbines covers the costs of assemblyconstruction of the foundation and tower connection to thenetwork installation of inverters control and automationmodules which on average make up about 25 of theequipment price

Investment in electrolyzers covers the costs of workshopconstruction creation of systems for water treatment andsupply electrolyte circulation and filtration gas collectionand purification and water condensation and cooling thesystems of automation and control (about 30 of the equip-ment cost)

Cost indices of the hydrogen tank are given per unit of itscapacity

5 Calculation Results and Their Analysis

For the first variant (scheme in Figure 1) Figure 5 presentselectricity cost values for wind turbines and diesel generators


Table 1 Technical and economic characteristics of the power system components

ComponentSpecific investments

($kW)lowastSpecific fixed costs( of investments) Efficiency ()lowastlowast Lifetime (years)

50 kW 1000 kW 50 kW 1000 kW 50 kW 1000 kW 50 kW 1000 kWCurrent indices

Diesel 500 315 7 5 32 35 10 10Wind turbine 1800 1300 3 2 35 35 20 20Electrolyzer 3500 1600 3 2 70 70 10 10Hydrogen tank 880 570 1 1 95 95 10 10Fuel cells 5000 3000 25 2 40 40 4 5

Prospective indicesDiesel 450 280 7 5 34 37 10 10Wind turbine 1600 1100 3 2 35 35 20 20Electrolyzer 2000 1000 35 25 77 77 20 20Hydrogen tank 600 400 1 1 98 98 20 20Fuel cells 2500 1500 35 25 60 60 10 10lowastSpecific investments for the hydrogen tank are given in $m3 lowastlowastefficiency of wind turbines is given for information (the calculations use wind turbinecharacteristics (power curve))

0

01

02

03

4 5 6 7 8

1

2

3

4

119878($

kW

h)

119881 (ms)

Figure 5 Cost of electricity generated by wind turbines anddiesel generators (fuel component at a fuel price of $800toe)for the scheme in Figure 1 1 wind turbine (50 kW) 2 windturbine (1000 kW) 3 diesel generator (50 kW) 4 diesel generator(1000 kW)

that are calculated by (5) with a discount rate 10 anddiesel price $800toe In this case to estimate the economicefficiency of wind turbines we should compare the cost ofpower generated by them to the fuel component of the costof power produced by diesel generators

Figure 5 shows that even at low long-term average annualwind speed (about 45ms) wind turbines are competitivewith diesel generatorsThis is indicative of a great potential ofwind turbines when used in the autonomous (decentralized)power supply systems both in coastal areas (coasts of seas andoceans) and in some continental regions of Russia

Figures 6 and 7 present the results of calculations forthe scheme presented in Figure 2 Technical and economicindices (current and prospective) correspond to the highload power (1000 kW in Table 1) In the calculations theelectrolyzer power was chosen to be optimal (at high wind

speed it turned out to be equal to the installed capacity ofwind turbines and at low wind speed less) the power of fuelcells was chosen according to the condition of constancy ofgenerated power and the hydrogen tank capacity was chosenaccording to the condition of continuous operation of fuelcells at their constant power during 120 hours

The cost of electricity in Figure 6(a) is compared to thecost of electricity generated by diesel generators (currentindices power of 1000 kW in Table 1) and the hydrogencost (Figure 6(b)) is compared to the price of diesel fuel Toprovide comparability we assume that diesel generator aswell as fuel cells operates with a capacity factor equal to 1As we can see according to current technical and economicindices (Table 1) the electricity generated by wind turbinesand hydrogen produced by electrolyzer are more expensivethan the electricity generated by diesel generator and dieselfuel respectively

The main component in the hydrogen cost is electrolyzerand in the electricity cost is fuel cells (Figure 7) Howeverin the future the hydrogen system will become competitivesince even in the case of relatively cheap fuel and an averagewind speed starting with 5-6ms fuel cells generate cheaperelectricity than diesel generators This is achieved thanksto a significant decrease in specific investment in fuel cells(Table 1) Moreover the cost of hydrogen becomes lower thanthe cost of diesel at higher wind speeds This is explainedby the higher efficiency of fuel cells as compared to dieselgenerators

Taking into account the obtained results the authorsmade calculations for the scheme in Figure 3 only for theprospective technical and economic indices (Figures 8 and 9)

Figure 8 presents the efficiency zones of energy technolo-gies (optimal structure of the system depending on the dieselprice and average wind speed) At low wind speed and lowprice of fuel it is reasonable to use only diesel generator tosupply power to consumers When the fuel price and wind


0

02

04

06

4 5 6 7 8

1

23

4

119881 (ms)

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

4 5 6 7 8

12

3

4

H2

pric

e ($

toe)

119881 (ms)

(b)

Figure 6 Cost of electricity generated by fuel cells (a) and cost of hydrogen supplied from the hydrogen tank (b) for the scheme in Figure 21 current indices of the system components 2 prospective indices 3 electricity from diesel generator at a fuel price of $800toe (a) and fuelprice of $800toe (b) 4 the same fuel price is $1400toe

0

02

04

06

1 2

WT ELHT FC

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

1 2

WTEL

HT

H2

pric

e ($

toe)

(b)

Figure 7 Structure of costs of electricity (a) and hydrogen (b) production at wind speed 6ms for the scheme in Figure 2 1 current indicesof the system components 2 prospective indices WT are the wind turbines EL is the electrolyzer HT is the hydrogen tank and FC are thefuel cells

speed increase first it becomes more economical to use awind-diesel system and then wind turbines with a hydrogensystem In the latter case according to the optimizationresults diesel generator is excluded from the system Costeffectiveness of wind turbines and fuel cells at a load of1000 kW is provided at lower wind speed and lower dieselprice than for a load of 50 kW since the specific indicesof larger energy sources are better When the load equals1000 kW the application of a diesel generator alone in theconsidered region of parameters turns out to be inefficient

Zones of technological efficiency allow us to determinethe best structure of the power supply system for the givenconditions Moreover we should know what economic effectcan be achieved by applying the optimal structure becauseonly if the effect is sufficient it makes sense to complicatethe system by adding extra components The correspondingdata are presented in Figure 9 As we can see the size of theachieved effect is quite significant

For example with the load of 1000 kW and the averagewind speed of 6ms the construction of wind turbines inaddition to diesel generator makes it possible to decrease

the electricity cost from 27 to 20 centkWh and the replace-ment of the diesel generator by an electrochemical unit to15 centkWhThus the introduction of a wind-hydrogen sys-tem will allow us to halve the costs of electricity productionas compared to power supply from diesel generator alone

6 Conclusion

The paper presents an analysis of the economic efficiency ofharnessing wind energy in the autonomous power systemsof Russia The wind turbines are shown to be competitive inmany considered variants (groups of consumers placementareas and climatic and meteorological conditions)

At the current prices of fossil (diesel) fuel the applicationof winddiesel systems is efficient even if the long-term aver-age annual wind speed on the wind turbine site is relativelylow (about 45ms) In the regions with a long-term averageannual wind speed higher than 5ms the application of windturbines can reduce the price of the generated electricity by50 or more (as compared to the use of diesel generatorsalone)


0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)

Figure 8 Zones of technological efficiencywith the load power of 50 kW(a) and 1000 kW (b) and prospective indices of electrolyzer hydrogentank and fuel cells for the scheme in Figure 3119881 is the average wind speed at a height of 10m 119901 is the diesel price WT are the wind turbinesDG is the diesel generator and FC are the fuel cells

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)

Figure 9 Electricity cost for the scheme in Figure 3 at a fuel price of $1100toe and with the load power of 50 kW (a) and 1000 kW (b) andprospective indices of electrolyzers hydrogen tanks and fuel cells 119881 is the average wind speed at a height of 10m 119901 is the diesel price DGis the diesel generator WT are the wind turbines and FC are the fuel cells

During the periods of strong wind some amount ofpower generated by wind turbines turns out to be redundantTherefore it becomes possible to use this power for hydrogenproduction by electrolysis and its subsequent electrochemicaltransformation into electricity Under certain conditions theintroduction of subsystem for hydrogen production storageand use for energy purposes to the winddiesel system candecrease diesel consumption (or even completely excludediesel generators from the system) and reduce the costs ofelectricity production

The study considered the possibility of storing energyin the form of hydrogen in the autonomous winddieselhydrogen power systems that include a diesel generatorelectrolyzer hydrogen tank and fuel cells The authorsdetermined the zones of economic efficiency in the systemdepending on the load power fuel price and long-termaverage annual wind speed

Technical and economic characteristics of the equipmentwhich is now available in the market still do not allowthe hydrogen system (electrolyzer hydrogen tank and fuelcells) to become competitive with diesel or wind-dieselpower plants However the indices projected for the nearestfuture (an approximately twofold decrease in specific capitalinvestment in fuel cells against the current level) make thehydrogen system economically efficient at the fuel prices

typical of the autonomous power systems ($800ndash$1400toe)and the average annual wind speed starting with 5-6msApplication of the system for the hydrogen production anduse for energy purposes will considerably reduce (more thanby 50) the costs of power supply to consumers

Nomenclature

119887 Specific fuel consumption (toekWh)119889 Annual discount rate119864(120591) Cash flow ($year)CF Capacity factorCRF Capital recovery factor (1year)119891(V) Wind turbine power curveℎ Annual number of utilization

hours (hoursyear)119867 8760 hoursyear119896 Specific investments ($kW)119870 Investments ($)119871 Load (kW)NPV Net present value ($)119901119890 Electricity price ($kWh)

119901119891 Fuel price ($toe)

119875 Power (kW)


119875lowast Energy equivalent of hydrogen in hydrogen

tank (kWh)119876 Electricity production (kWhyear)119878 Electricity cost ($kWh)119905 Time (hours)119879 Lifetime (year)119880 Power surplus (kW)119881 Average wind speed (ms) at a height of 10m1199110 Roughness (m)

119885 Average annual costs ($year)Δ119905 Time step (hours)120572 Shape parameter of the Weibull distribution120590 Discount coefficient (1year)120578 Efficiency120579 Energy equivalent (kWhtoe)120583 Specific constant costs (share of investments)$ The US dollar

Indices

119894 Type of power plantmax Maximummin Minimum

Abbreviations

DG Diesel generatorDL Dump loadEL ElectrolyzerFC Fuel cellsHT Hydrogen tankOampM Operation and maintenanceRES Renewable energy sourcesWT Wind turbines

Acknowledgment

The study was supported by the Ministry of Educationand Science of the Russian Federation (State Contract no07514114099)

References

[1] O V Marchenko and S V Solomin ldquoEfficiency of wind energyutilization for electricity and heat supply in northern regions ofRussiardquo Renewable Energy vol 29 no 11 pp 1793ndash1809 2004

[2] O V Marchenko and S V Solomin ldquoAssessment of theeconomic and environmental efficiency of solar heat supply inRussiardquoThermal Engineering vol 48 no 11 pp 928ndash931 2001

[3] O V Marchenko and S V Solomin ldquoThe analysis of hydrogenproduction efficiency with application of wind turbines andits use in autonomous energy systemrdquo International ScientificJournal for Alternative Energy and Ecology vol 3 no 47 pp 112ndash118 2007

[4] O V Marchenko and S V Solomin ldquoThe analysis of economiceffectiveness of renewable energy sources in dezentralizedenergy systemsrdquo International Scientific Journal for AlternativeEnergy and Ecology vol 5 no 73 pp 78ndash84 2009

[5] O V Marchenko and S V Solomin ldquoThe investigation ofeconomic efficiency of wind turbines in dezentralized energysystemsrdquo International Scientific Journal for Alternative Energyand Ecology vol 1 no 81 pp 126ndash131 2010

[6] O V Marchenko ldquoMathematical modeling and economicefficiency assessment of autonomous energy system with pro-duction and storage of secondary energy carriersrdquo InternationalJournal of Low-Carbon Technologies vol 5 no 4 pp 250ndash2552010

[7] O V Marchenko ldquoMathematical model of energy system withrenewable energy sourcesrdquo Izvestia RAN Energetika no 3 pp154ndash161 2006 (Russian)

[8] L S Belyaev S P Filippov O VMarchenko et alWorld Energyand Transition to Sustainable Development Kluwer AcademicPublishers London UK 2002

[9] L S Belyaev O V Marchenko and S V Solomin ldquoStudyof long-term trends in the development of renewable energysourcesrdquo Perspectives in Energy vol 11 no 1 pp 9ndash17 2007

[10] O V Marchenko and S V Solomin ldquoSystem studies foranalyzing the efficiency of renewable energy sourcesrdquo ThermalEngineering vol 57 no 11 pp 919ndash924 2010

[11] L S Belyaev O V Marchenko and S V Solomin ldquoA study ofwind energy contribution to global climate change mitigationrdquoInternational Journal of Energy Technology and Policy vol 3 no4 pp 324ndash341 2005

[12] L S Belyaev O V Marchenko S P Filippov and S V SolominldquoStudies on competitiveness of space and terrestrial solar powerplants using global energy modelrdquo International Journal ofGlobal Energy Issues vol 25 no 1-2 pp 94ndash108 2006

[13] Global Wind Report Annual Market update 2011 Global WindEnergy Council Brussels Belgium 2012

[14] World Wind Energy Report 2010 WWEA Bonn Germany2010

[15] O V Marchenko ldquoMathematical modelling of electricity mar-ket with renewable energy sourcesrdquo Renewable Energy vol 32no 6 pp 976ndash990 2007

[16] O V Marchenko ldquoModeling of a green certificate marketrdquoRenewable Energy vol 33 no 8 pp 1953ndash1958 2008

[17] S Thomas and F Lomax Low-Cost Hydrogen Distributed Pro-duction Systems 2006 DOE Hydrogen Program Review H2GenInnovations 2006

[18] D Rastler Status Trends andMarket Forecast for Stationary FuelCell EPRI Ohio USA 2005

[19] K-A Adamson Fuel Cell Today Market Survey Large Station-ary Applications London UK 2006

[20] J Cotrell W Pratt et al ldquoModeling the feasibility of usingfuel cells and hydrogen internal combustion engines in remoterenewable energy systemsrdquo NRELTP 500-34648 Golden2003

[21] M Beccali S Brunone M Cellura and V Franzitta ldquoEnergyeconomic and environmental analysis on RET-hydrogen sys-tems in residential buildingsrdquo Renewable Energy vol 33 no 3pp 366ndash382 2008

[22] R S Garcia and D Weisser ldquoA wind-diesel system withhydrogen storage joint optimisation of design and dispatchrdquoRenewable Energy vol 31 no 14 pp 2296ndash2320 2006

[23] D B Nelson M H Nehrir and C Wang ldquoUnit sizing andcost analysis of stand-alone hybrid windPVfuel cell powergeneration systemsrdquo Renewable Energy vol 31 no 10 pp 1641ndash1656 2006


[24] B E Turkay and A Y Telli ldquoEconomic analysis of stand aloneand grid connected hybrid energy systemsrdquo Renewable Energyvol 36 no 7 pp 1931ndash1943 2011

TribologyAdvances in

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

AerospaceEngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

FuelsJournal of


Journal ofPetroleum Engineering


Industrial EngineeringJournal of


Power ElectronicsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

CombustionJournal of


Journal of


Renewable Energy

Submit your manuscripts athttpwwwhindawicom


StructuresJournal of


RotatingMachinery


EnergyJournal of


Hindawi Publishing Corporation httpwwwhindawicom

Journal ofEngineeringVolume 2014

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal ofPhotoenergy


Nuclear InstallationsScience and Technology of


Solar EnergyJournal of


Wind EnergyJournal of


Nuclear EnergyInternational Journal of


High Energy PhysicsAdvances in

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


(i) settlements are spread throughout large scarcely pop-ulated territories

(ii) electric load of consumers in each settlement does notexceed 1ndash3MW

(iii) transport infrastructure is underdeveloped

(iv) the main electricity source is diesel power plants

(v) diesel power plants use expensive diesel fuel whichusually costs more than $800ndash$1000toe [4]

Therefore the introduction of renewables to increase thecost effectiveness of power supply is an urgent problem forthese systems One of the most effective types of RES is windturbines [1 4]

In 2011 the total installed capacity of all wind turbinesoperating in the world accounted for 238GW (increasedby 20 as compared to 2010) [13] Wind turbines generateabout 25 of the total electricity production in the world Asopposed to both many developed and developing countriesRussia uses wind energy very little The installed capacity ofwind turbines is about 20MW and the rate of wind energydevelopment was less than 10 in 2010 and 2011 [14] Theshare of wind turbines in the total electricity production inRussia is negligible (less than 001)

Meanwhile the potential for the wind energy develop-ment in Russia is really great Russia has the longest shorelinein theworld abundant treeless flatlands and largewater areasof inner rivers lakes and seas which represent the mostfavorable sites for wind turbines

The main advantages of wind turbines are as follows

(i) no harmful emissions in the process of electricityproduction

(ii) relative cheapness of generated electricity (3ndash5 centkWh for the best turbines under good windconditions)

(iii) possibility of significantly saving on fossil fuel in thecourse of operation in an autonomous power system

At the same time wind turbines have a flaw This isan unsteady electricity generation (depending on changesin wind speed) Therefore wind turbines are used incombination with energy sources that operate under thecontrolled conditions and supply power to the load whenpower generated by wind turbines is insufficient or duringtheir downtime Besides power systems with wind turbinesinclude energy storage devices

The research aims to study the economic efficiencyof harnessing wind energy in Russia for a wide range ofparameters (fossil fuel price climatic and meteorologicalconditions power and load curve of consumers and cur-rent and prospective technical and economic indices ofthe power system components) First of all the authorsconsider the most promising winddiesel systems includingthe systems that produce store and use hydrogen in fuel cells(winddieselhydrogen systems)

Dumpload

Load

Windturbine

Diesel

simsim

Figure 1 Winddiesel system

2 Variants of Harnessing Wind Energy

The authors consider three variants of harnessing windenergy in the autonomous power systems to supply power toconsumers

In the first variant wind turbines are included in thewinddiesel system (Figure 1) The capacity of a diesel gener-ator is chosen so that it provides uninterrupted power supplyto consumers even in the case of wind turbine downtimeduring calms In the periods of strong wind however someamount of power generated from wind turbines turns out tobe redundant and is diverted to the dump load

The other two variants allow for the storage of energy inthe form of hydrogen produced by electrolysis and electro-chemically transformed into electric energy Under certainconditions the introduction of a subsystem for productionstorage and use of hydrogen for energy purposes into thewinddiesel system can decrease the diesel fuel consumption(or even exclude the diesel generator from the system) andreduce the costs of electricity production

The second variant considers a simplified (linear) schemein which electric energy or hydrogen sequentially passesthrough the system components diesel generator is excluded(Figure 2) Here it is assumed that the volume of hydrogenproduced is sufficient to have constant electric power offuel cells This means that the combination of wind turbineswith stochastic power generation and a hydrogen system(electrolyzer hydrogen tank and fuel cells) allows us toobtain a new property of the energy source that is constantgeneration (by additional costs) If the installed capacity ofan electrolyzer is lower than the capacity of wind turbinessome amount of the generated electricity may turn out tobe redundant and will be diverted to the dump load Theuse of excess electricity in heat supply (as well as the heatgenerated by fuel cells) was not considered in this paper Infact the utilization of this heat can prove to be economicaland increase the efficiency of the whole system [1] Howeverthis will require the introduction of additional componentsinto the scheme (heat exchangers pipelines pumps etc) andmore detailed consideration of consumer specific featureswhich goes beyond the scope of this paper

In the third variant (Figure 3) the autonomous powersystem includes diesel units one or several wind turbineselectrolyzer hydrogen tank fuel cells and electricity con-sumers with their load curve It is assumed that the diesel


Windturbine

Dumpload

Load

Fuelcells


simsim

==


Windturbine


Fuel cell

Diesel

Load

Dumploadsim

simsim

sim

=

=






NPV = int

119879

0

119864 (120591) exp (minus120590120591) 119889120591 (1)



Then


119879

0

(119901119890119876 minus 119885) exp (minus120590120591) 119889120591

=1


(2)




119885 = 120583119870 + 119901119891119887119876 (3)



NPV =1

120590[1 minus exp (minus120590119879)]119876 (119901

119890minus 119878) (4)

where

119878 =CRF sdot 119870 + 119885

119876=119896

ℎCRF + 119896

ℎ120583 +

119901119891

120579 sdot 120578(5)





119891= 0)







119878 =1

119876[sum

119894

CRF119894119870119894+ 119885119894] 997888rarr min (6)

subject to

119875DG (119905) + 119875WT (119905) + 119875FC (119905) = 119871 (119905) + 119880 (119905) (7)

0 le 119875119894 (119905) le 119875

119894max (8)

119880 (119905) ge 0 (9)

119875WT (119905) = 119875WT max119891 (V) (10)

119875FC (119905) le119875lowast

HT (119905) 120578HT120578FC

Δ119905 (11)

119875EL (119905) = min(119880 (119905) (119875lowast


HT (119905)

(120578ELΔ119905))) (12)

119875lowast

HT (119905) = 119875lowast


(120578FC120578HT)]Δ119905

(13)







4 Initial Data








Pacific Ocean

Arctic Ocean





























0

01

02

03

4 5 6 7 8

1

2

3

4

119878($

kW

h)

119881 (ms)











0

02

04

06

4 5 6 7 8

1

23

4

119881 (ms)

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

4 5 6 7 8

12

3

4

H2

pric

e ($

toe)

119881 (ms)

(b)


0

02

04

06

1 2

WT ELHT FC

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

1 2

WTEL

HT

H2

pric

e ($

toe)

(b)






6 Conclusion




0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)


0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)






Nomenclature




119875 Power (kW)





Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of


















Windturbine

Dumpload

Load

Fuelcells


simsim

==


Windturbine


Fuel cell

Diesel

Load

Dumploadsim

simsim

sim

=

=






NPV = int

119879

0

119864 (120591) exp (minus120590120591) 119889120591 (1)



Then


119879

0

(119901119890119876 minus 119885) exp (minus120590120591) 119889120591

=1


(2)




119885 = 120583119870 + 119901119891119887119876 (3)



NPV =1

120590[1 minus exp (minus120590119879)]119876 (119901

119890minus 119878) (4)

where

119878 =CRF sdot 119870 + 119885

119876=119896

ℎCRF + 119896

ℎ120583 +

119901119891

120579 sdot 120578(5)





119891= 0)







119878 =1

119876[sum

119894

CRF119894119870119894+ 119885119894] 997888rarr min (6)

subject to

119875DG (119905) + 119875WT (119905) + 119875FC (119905) = 119871 (119905) + 119880 (119905) (7)

0 le 119875119894 (119905) le 119875

119894max (8)

119880 (119905) ge 0 (9)

119875WT (119905) = 119875WT max119891 (V) (10)

119875FC (119905) le119875lowast

HT (119905) 120578HT120578FC

Δ119905 (11)

119875EL (119905) = min(119880 (119905) (119875lowast


HT (119905)

(120578ELΔ119905))) (12)

119875lowast

HT (119905) = 119875lowast


(120578FC120578HT)]Δ119905

(13)







4 Initial Data








Pacific Ocean

Arctic Ocean





























0

01

02

03

4 5 6 7 8

1

2

3

4

119878($

kW

h)

119881 (ms)











0

02

04

06

4 5 6 7 8

1

23

4

119881 (ms)

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

4 5 6 7 8

12

3

4

H2

pric

e ($

toe)

119881 (ms)

(b)


0

02

04

06

1 2

WT ELHT FC

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

1 2

WTEL

HT

H2

pric

e ($

toe)

(b)






6 Conclusion




0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)


0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)






Nomenclature




119875 Power (kW)





Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of





















119878 =1

119876[sum

119894

CRF119894119870119894+ 119885119894] 997888rarr min (6)

subject to

119875DG (119905) + 119875WT (119905) + 119875FC (119905) = 119871 (119905) + 119880 (119905) (7)

0 le 119875119894 (119905) le 119875

119894max (8)

119880 (119905) ge 0 (9)

119875WT (119905) = 119875WT max119891 (V) (10)

119875FC (119905) le119875lowast

HT (119905) 120578HT120578FC

Δ119905 (11)

119875EL (119905) = min(119880 (119905) (119875lowast


HT (119905)

(120578ELΔ119905))) (12)

119875lowast

HT (119905) = 119875lowast


(120578FC120578HT)]Δ119905

(13)







4 Initial Data








Pacific Ocean

Arctic Ocean





























0

01

02

03

4 5 6 7 8

1

2

3

4

119878($

kW

h)

119881 (ms)











0

02

04

06

4 5 6 7 8

1

23

4

119881 (ms)

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

4 5 6 7 8

12

3

4

H2

pric

e ($

toe)

119881 (ms)

(b)


0

02

04

06

1 2

WT ELHT FC

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

1 2

WTEL

HT

H2

pric

e ($

toe)

(b)






6 Conclusion




0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)


0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)






Nomenclature




119875 Power (kW)





Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of


















Pacific Ocean

Arctic Ocean





























0

01

02

03

4 5 6 7 8

1

2

3

4

119878($

kW

h)

119881 (ms)











0

02

04

06

4 5 6 7 8

1

23

4

119881 (ms)

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

4 5 6 7 8

12

3

4

H2

pric

e ($

toe)

119881 (ms)

(b)


0

02

04

06

1 2

WT ELHT FC

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

1 2

WTEL

HT

H2

pric

e ($

toe)

(b)






6 Conclusion




0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)


0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)






Nomenclature




119875 Power (kW)





Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of
























0

01

02

03

4 5 6 7 8

1

2

3

4

119878($

kW

h)

119881 (ms)











0

02

04

06

4 5 6 7 8

1

23

4

119881 (ms)

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

4 5 6 7 8

12

3

4

H2

pric

e ($

toe)

119881 (ms)

(b)


0

02

04

06

1 2

WT ELHT FC

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

1 2

WTEL

HT

H2

pric

e ($

toe)

(b)






6 Conclusion




0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)


0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)






Nomenclature




119875 Power (kW)





Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of


















0

02

04

06

4 5 6 7 8

1

23

4

119881 (ms)

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

4 5 6 7 8

12

3

4

H2

pric

e ($

toe)

119881 (ms)

(b)


0

02

04

06

1 2

WT ELHT FC

119878($

kW

h)

(a)

0

500

1000

1500

2000

2500

1 2

WTEL

HT

H2

pric

e ($

toe)

(b)






6 Conclusion




0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)


0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)






Nomenclature




119875 Power (kW)





Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of


















0

500

1000

1500

2000

4 5 6 7 8

DG

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(a)

0

400

800

1200

4 5 6 7 8

119901($

toe)

119881 (ms)

DG +WT

WT + FC

(b)


0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG

+WT

WT + FC

119878($

kW

h)

(a)

0

01

02

03

04

4 5 6 7 8119881 (ms)

DG

DG +WT

WT + FC

119878($

kW

h)

(b)






Nomenclature




119875 Power (kW)





Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of





















Indices


Abbreviations


Acknowledgment


References






























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of























FuelsJournal of







Advances in



Journal of


Renewable Energy





RotatingMachinery


EnergyJournal of

















research article economic efficiency assessment of ...(wind/diesel/hydrogen systems). dump load load...

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