V2G: Vehicle to Grid PowerV2G: Vehicle to Grid Power

Seth InsleySeth Insley

CH 407HCH 407H

ConceptConcept

Cars use large amounts of powerCars use large amounts of power– Far more than other power usesFar more than other power uses

750 GW electric vs 12 TW from cars750 GW electric vs 12 TW from cars

– Must generate or store it themselvesMust generate or store it themselves– Unused most of the timeUnused most of the time

Average use only 1 hour per dayAverage use only 1 hour per day

Fuel cell, hybrid and battery cars generate Fuel cell, hybrid and battery cars generate power as electricitypower as electricity– Why not hook them up to the power grid?Why not hook them up to the power grid?

Conventional ViewConventional View

V2G ViewV2G View

ExamplesExamples

Use the battery in plug-in hybrid/battery Use the battery in plug-in hybrid/battery cars to buy cheap power at night and sell cars to buy cheap power at night and sell during the dayduring the day

Use hybrid/fuel cell car to generate peak Use hybrid/fuel cell car to generate peak powerpower

Use either to provide ‘spinning’ reserve or Use either to provide ‘spinning’ reserve or regulation servicesregulation services

BenefitsBenefits

Better utilize existing generation capacityBetter utilize existing generation capacity– Will need to build fewer new electric plantsWill need to build fewer new electric plants– Allow better load balancing by diversifying the Allow better load balancing by diversifying the

electric grid electric grid – Reduce transport load on grid by distributing Reduce transport load on grid by distributing

generationgeneration– Increase grid reliabilityIncrease grid reliability

Provide income to car ownersProvide income to car owners– Offset or reduce the cost of the carOffset or reduce the cost of the car

ConsiderationsConsiderations

How will vehicles be connected to the How will vehicles be connected to the grid?grid?

How will this effect drivers?How will this effect drivers?

Is this a cost effective way to generate Is this a cost effective way to generate power?power?

InfrastructureInfrastructure

Requires physical connection between car and Requires physical connection between car and gridgrid– Only useful when parkedOnly useful when parked– Could hook up at homeCould hook up at home– Could be incorporated into public charging stations or Could be incorporated into public charging stations or

parking lotsparking lots– Should be simple to set up, automatically handling Should be simple to set up, automatically handling

payment, etcpayment, etcJust plug it inJust plug it in

May also desire fuel connection:May also desire fuel connection:– Natural gas or hydrogenNatural gas or hydrogen

Driver ExperienceDriver Experience

Primary Consideration: Will this affect Primary Consideration: Will this affect range?range?– Allow owner to easily limit extent of Allow owner to easily limit extent of

discharge/fuel usedischarge/fuel use

Will it be easy to set up?Will it be easy to set up?Will it be sufficiently profitable to make it Will it be sufficiently profitable to make it worth the effort?worth the effort?– The car owner should not have to worry about The car owner should not have to worry about

thisthis– Only sell power when profitableOnly sell power when profitable

EconomicsEconomics

Not worthwhile unless it returns sufficient Not worthwhile unless it returns sufficient amounts of money after expenses incurredamounts of money after expenses incurred– Cost of fuel/ electricityCost of fuel/ electricity– Maintenance costs for Maintenance costs for

BatteryBattery

Fuel cellFuel cell

EngineEngine

– Effort required by ownerEffort required by owner

Economic AdvantagesEconomic Advantages

Very low capital costsVery low capital costs– Car already boughtCar already bought

Adding grid capabilities relatively cheapAdding grid capabilities relatively cheap

– Even so, costs roughly $60/kwEven so, costs roughly $60/kwCompared to $1000/kw for traditional generatorsCompared to $1000/kw for traditional generatorsDue to lower efficiencies, reliabilityDue to lower efficiencies, reliability

Has freedom to buy/sell only when Has freedom to buy/sell only when profitableprofitable– Much more responsive than traditional Much more responsive than traditional

generatorsgenerators

Economic DisadvantagesEconomic Disadvantages

Poor EfficiencyPoor Efficiency– Smaller/cheaper generators are less efficientSmaller/cheaper generators are less efficient– Need more fuel to generate same powerNeed more fuel to generate same power

Requires relatively expensive fuelsRequires relatively expensive fuels– Gasoline or hydrogen or natural gas vs coal Gasoline or hydrogen or natural gas vs coal – Cannot buy fuel in bulkCannot buy fuel in bulk

Economic ConclusionsEconomic Conclusions

Not suitable for baseline power generationNot suitable for baseline power generation– Cost of power to high vs. conventional generators Cost of power to high vs. conventional generators

~5~5¢/kwH vs >10¢/kwH¢/kwH vs >10¢/kwH

– Unique Advantages not usedUnique Advantages not used

Suitable for Suitable for – Peak power generationPeak power generation– Spinning ReservesSpinning Reserves– Power RegulationPower Regulation

Economic analysis depend heavily on exact Economic analysis depend heavily on exact assumptionsassumptions

Cost of generationCost of generation

Cost per kwhCost per kwh

Batteries (charged at base rate)Batteries (charged at base rate)– Lead acid $.23Lead acid $.23– NiCad $.32NiCad $.32– NiMH $.45NiMH $.45

Hybrid generating w/ gasoline $.20 Hybrid generating w/ gasoline $.20

Fuel Cell w/ H2 $.09-$.38Fuel Cell w/ H2 $.09-$.38

Peak GenerationPeak Generation

Used when electricity needs are much Used when electricity needs are much higher than baseline higher than baseline – During daytime, hot/cold weather, etc.During daytime, hot/cold weather, etc.

Considerably more expensive than Considerably more expensive than baselinebaseline– Often Generated by natural gasOften Generated by natural gas

Low capital, high incremental expenseLow capital, high incremental expense

– ~200 hours a year where > 50~200 hours a year where > 50¢ kwh¢ kwh

Economics of Peak GenEconomics of Peak Gen

Not to slightly profitable for batteriesNot to slightly profitable for batteries– Depends on current power marketsDepends on current power markets

Can be fairly profitable for fuel cellsCan be fairly profitable for fuel cells– ~1k / year~1k / year

Less so for hybridsLess so for hybrids– ~.5k / year~.5k / year

Spinning ReserveSpinning Reserve

Generators ready to provide power in ~10 Generators ready to provide power in ~10 minmin

Used to preserve grid stability if Used to preserve grid stability if generators go down, load is too highgenerators go down, load is too high

Sold on contract basis Sold on contract basis – Ex. 1 Kw for a dayEx. 1 Kw for a day– Payment even if not usedPayment even if not used– Extra payment if usedExtra payment if used

Spinning EconomicsSpinning Economics

Profitable for all vehicle typesProfitable for all vehicle types– Batteries $10-$700Batteries $10-$700– Fuel cell, hybrid generating: ~$2000Fuel cell, hybrid generating: ~$2000

Power RegulationPower Regulation

Used to keep frequency stable at 60 HzUsed to keep frequency stable at 60 Hz

Must be able to respond instantlyMust be able to respond instantly

2 kinds2 kinds– Regulation up – generating powerRegulation up – generating power– Regulation down – absorbing powerRegulation down – absorbing power

Regulation EconomicsRegulation Economics

Batteries are ideal for this purposeBatteries are ideal for this purpose– Up/down corresponds to discharge/chargeUp/down corresponds to discharge/charge– Has minimal effect on total charge Has minimal effect on total charge – ~3k for lead acid~3k for lead acid– ~2k for NiMH~2k for NiMH– Actual degradation hard to determineActual degradation hard to determine

Not profitable for other typesNot profitable for other types

Market SizeMarket Size

All numbers for CA electric marketAll numbers for CA electric market

~300k battery vehicles for regulation~300k battery vehicles for regulation

76k – 273k vehicles for spinning reserve76k – 273k vehicles for spinning reserve

~ 734k vehicles at max for peak ~ 734k vehicles at max for peak

.5% – 5% of total light vehicle count.5% – 5% of total light vehicle count

Additional uses are likely in a saturated Additional uses are likely in a saturated marketmarket– More reliability, renewableMore reliability, renewable

ConclusionConclusion

V2G is a promising conceptV2G is a promising concept– Provides a cheaper way to provide many grid Provides a cheaper way to provide many grid

servicesservices

Needs more detailed studyNeeds more detailed study

Not hard to implement simplyNot hard to implement simply

May play an important role in the future May play an important role in the future power gridpower grid

SourcesSources

V2G research group at U of DE. “V2G: Vehicle V2G research group at U of DE. “V2G: Vehicle To Grid Power” To Grid Power” http://www.udel.edu/V2G/http://www.udel.edu/V2G/

Kempton, et. al. “Vehicle-to-Grid Power” Kempton, et. al. “Vehicle-to-Grid Power” http://www.udel.edu/V2G/V2G-Cal-2001.pdfhttp://www.udel.edu/V2G/V2G-Cal-2001.pdf

Kempton, Letendre. “Electric Vehicles as a new Kempton, Letendre. “Electric Vehicles as a new Source of Power for Electric Utilities” Source of Power for Electric Utilities” http://www.udel.edu/V2G/Kempton-Letendre-http://www.udel.edu/V2G/Kempton-Letendre-97.pdf97.pdf