Electric Cars Dr.Boehm's Presentation

7/30/2019 Electric Cars Dr.Boehm's Presentation

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LECTURE 22

HYDROGEN AND ELECTRIC VEHICLES

FINAL BOEHM LECTURE!



THIS LECTURE• For a number of reasons the growing use of petroleum-based fuels for transportation purposes is not a goodidea. Included are import/economic issues as well asproblems posed to the environment.

• If advanced approaches to vehicles are considered, thetwo top choices for powering them appear to be hydrogenand electricity. Although both approaches are clearlytechnically feasible and both suffer from lack of infrastructure, the electric vehicle currently has severalcharacteristics that make it a more viable short-term

transition approach. Hydrogen may ultimately be theenergy source of choice for vehicles, but we will have towait and see.

• In this lecture both approaches are explored.



HYDROGENAND FUEL

CELLS



WHAT MANY PEOPLE THINK

ABOUT WHEN THEY HEAR“HYDROGEN”

The Hindenburg



Hart, Front EcolEnviron, 2003;

1(3):138-145



FLAMMABILITY OF

HYDROGEN



The U.S. hydrogen industry currently produces 9 million tons of hydrogen per year (enough to power 20-30 million cars or 5-8million homes) for use in:

• Chemicals production• Petroleum refining

• Metals treating

• Electrical applications.



• Most hydrogen used today is manufactured this way.

• Natural gas and steam are heated to high temperature

(usually by combusting part of the fuel), and hydrogen is

removed.

• Not a sustainable method.

• Green houses gases are produced.

• City of Las Vegas has this type of hydrogen generationsystem but it is not longer in use.







Electrolyzer with solar power.Joint project with the UNLV, Las Vegas Valley Water District, Proton Energy.Located across Alta from Las Vegas Springs Preserve.



THE LVVWD STATION

Powered by a!PV system, total of

14 kW peak rating.Single-axis

tracking.



UNLV





PROTON EXCHANGE MEMBRANE

(PEM) FUEL CELL

• Operates at low temperatures (~175°F)

• Has high power density

• Can ramp power relatively quickly (not as fast as an ICE,however)

• Usually uses expensive membrane (Nafion) coated withplatinum catalyst particles (membrane allows hydrogenmolecules to flow through)

• Outputs typically up to about 250 kW• We have some small sizes of these <5 kw





FUEL CELL ENERGY BALANCE



FUEL CELL VEHICLESThese can be either fuel cell/electric hybrids, hydrogeninternal combustion engine (ICE) powered, or ICE/hybridpowered.



HONDA FCX CLARITY (2010)



HONDA FCX CLARITY



UNLV VEHICLEELECTRIC-FUEL CELL HYBRID



FUEL CELL VEHICLE CONVERSION SYSTEM DIAGRAM

5.5 kWFuel Cell

DC/DCConverter

Deep CycleBattery bank

Solid-StateMotor Speed

Controller

11.5 hpDC Motor

Controller



UNLV/LVVWD



FULL SIZE FC VEHICLE ECONOMYFROM US PROGRAM



BMW GASOLINE/HYDROGEN ICE



Polaris ICE Single Cylinder

Vehicles were to be used atthe Las Vegas SpringsPreserve. Color scheme isfor that application

Taylor Dunn Electrotruk FCVehicle







Preferable





VEHICLE POWER COMPARISONS

Gasoline-Powered Car (ICE)

• Lot of parasite power uses.

• Limited by Carnot considerations related to rejected heat.

• Overall efficiency is about 20% fuel to power.



VEHICLE POWER COMPARISONS

Hydrogen-Powered Car (ICE)

• Similar to gasoline-powered car, but much cleaner burning.

• Limited by Carnot considerations related to rejected heat.

• Overall efficiency is slightly less than gasoline because of lowdensity of fuel. Can be improved using turbo or supercharging.



Fuel-Cell-Powered Electric Car (Renewable Electricity)

• Fuel cell has potential to be up to 80% efficient

• Motor/inverter efficiency is about 90%

• Conversion of electricity to hydrogen is about 50%

• So total of conversion for electricity to power is 36%

• (Could go from methanol to power via H2 at 24-32%)



HYDROGEN SAFETY



What follows is from a

presentation given by

Travis Johnson, P.E.Manager, Electric Transportation & Emerging Technology

NV Energy



SOME QUESTIONS TO BE

ADDRESSED

1) What kind of plug-in cars are coming?

2) Will plug-in cars be affordable?

3) How much does it cost to drive electric

4) How much will plug-in cars reduce greenhouseemissions?

5) How many cars can the grid handle in Nevada?

6) What about charging and the battery?



NV ENERGY SUPPORTING

ELECTRIC VEHICLESDiscounted EV rate in southern NV

Discounted EV rate (coming soon to northern NV)

Ramping up internal readiness for EVs

Including in company vehicle fleetOutreach and education about EVs



WHAT EVS ARE HERE?

Battery Electric (BEV)100 mile range (total)

90+ MPH

8 yr, 100k mile battery warranty

Does not use gasoline

Good for average commuter

Very low maintenance

Plug-in Hybrid (PHEV)• 40 mi. electric, then 300 mi. gas

• 90+ MPH

• 8 yr, 100k mile battery warranty

• Gas extends range beyond 40 mi.

• Best for long commutes

• Typical maintenance (oil, filter, etc.)

Nissan Leaf Chevy Volt



WHAT IS COMING?Ford, Chevy, Nissan, Toyota, Tesla all making Lithium Ion based electric drive

vehicles – all the vehicles below plug-in

2010/11

2010/11 BEV

2011 BEV

2013?

20112011201120112011

PHEV

2010/11 BEV

2012 PHEV

2010/11 PHEV2012 BEV

Now SellingNow Selling



ARE THEY AFFORDABLE?

Nissan Leaf:

§ Buy: $25,280 after tax credit

§ Lease: $349/month

Chevy Volt: § $33,500 after tax credit

§ Lease $350/month



HOW MUCH ELECTRICAL ENERGY DO

THEY USE?

Tesla Roadster ~ 3.3 miles / kWh(185 kW motor)

Nissan Leaf ~ 4 miles / kWh

Chevy Volt ~ 4 miles / kWh





HOW MUCH DOES ELECTRICAL

ENERGY COST?NV Energy (south) HEV Rate:

§ Approximately 1/3 to 1/4 the cost of gas

§ 6.3 cents / kWh winter off-peak (8 months)

§ 7.3 cents / kWh summer off-peak (4months)

§ 12 cents / kWh flat rateOff peak 10pm – 6am

The Pacific Northwest National Lab found that 9 cent / kWhelectrical energy is equivalent to $1/gal gas. Simple ratios were

used to simulate prices.



DOLLAR SAVINGS FOR 12,000

MILES PER YEAR?EV (Nissan Leaf)Fuel Cost:

4 mi. / kWh = 3000 kWh

6.6 cents / kWh = $198*

Similar Gas VehicleFuel Cost:

• 24 MPG = 500 gallons

• Gas $2.42/gal = $1,210**

Nissan Leaf $25,280 Honda Civic Si $24,255

$1,210 (gas without taxes)- $ 198 (electric) $1,012 savings per year*

* NV Energy (south) TOU Rate for Plug-in Vehicles charging at night.

**$3/gal less 58.27 cents per gallon for federal, state, RTC, & county tax for

apples to apples.



DOLLAR SAVINGS FOR 12,000

MILES PER YEAR?EV (Nissan Leaf)Fuel Cost:

4 mi. / kWh = 3000 kWh

12 cents / kWh = $360

Large SUVFuel Cost:

• 15 MPG = 800 gallons

• Gas $2.42/gal = $1,936**

$1,936 (gas without taxes)- $ 360 (electric) $1576 savings per year*

* NV Energy (north) flat residential electric rate 12 cents/kWh.

**$3/gal less 58.27 cents per gallon for federal, state, RTC, & county tax for

apples to apples.



HOW MANY POUNDS OF CO2 PER KWH

DOES THE GRID CREATE?

0.902

0.724

1.311

1.883

1.821

1.324

1.658

1.9601.830

1.537

1.510

1.489

1.134

1.019

1.318

1.5631.563

1.8340.927

0.498

1.514

1.139

National Average ~ 1.3 lbs/kWh - Source eia.doe.gov



HOW MANY POUNDS OF CO2 PER

GALLON?

Burning one gallon of gas produces 19.4 lbs. of CO2. – EPA

Refining emissions increases this by 5.4 lbs of CO2 – Fueleconomy.gov.

Total with refining emissions: 24.8 lbs CO2/gallon

Does not includeextraction andtransportation

emissions to refinery.



CO2 REDUCTION FOR

12,000 MILES PER YEAR?

Nissan Leaf $25,280 Honda Civic Si $24,255

EV (Nissan Leaf)• 4 mi. / kWh = 3000 kWh

• 1.3 lb / kWh = 3900 lbs.*

Similar Gas Vehicle• 24 MPG = 500 gallons

• 24.8 lbs / gal = 12,400 lbs

12,400 lbs CO2 (gas)

- 3,900 lbs CO2 (electric) 8,500 lbs CO2 savings per year

* Based on EIA’s 1.3 lb/kWh national average.



CO2 REDUCTION FOR

12,000 MILES PER YEAR?

EV (Nissan Leaf)• 4 mi. / kWh = 3000 kWh

• 1.3 lb / kWh = 3900 lbs.*

Large SUV• 15 MPG = 800 gallons

• 24.8 lbs / gal = 19,840 lbs

19,840 lbs CO2 (gas)

- 3,900 lbs CO2 (electric) 15,940 lbs CO2 savings per year

Based on EIA’s 1.3 lb/kWh national average.



WHAT IS THE LARGEST

HOUSEHOLD CO2 SOURCE?

Source: fueleconomy.org



HOW MANY EVS CAN THE

GRID CHARGE AT NIGHT?

2000 MW

NV Energy (Vegas) System Load – July 2008



HOW MANY EVS CAN THE

GRID CHARGE IN VEGAS?

§ The Chevy Volt will have a 16 kWhbattery (maintained SOC of 8 kWh)

§ If charged at 2kW x 4 hrs

§ 1 MW = 500 vehicles charging at thesame time

§ At night in Vegas, peak is ~2,000 MWhigher than off peak (night)

§ Could charge ~1,000,000 Chevy Voltsat night without significant electricsystem improvements

If the charge rate was4kW, that would resultin 500,000 vehiclesbeing able to charge at

the same time.Random distribution isassumed. The point issimple, a lot of vehiclescan charge at night.



CHARGE TIME DEPENDS ON

DISTANCE DRIVEN

Source: Nissan

Approximately 12.5 miles of range per hour of charging.



CHARGING – HOW WILL IT

WORK?

Chevy Volt – On board 120 V Cordset



CHARGING – HOW WILL IT WORK?

3.3 kW 240 V onboard charger

Also has a 120 V onboard Cordset.



WHAT ABOUT THE BATTERY?

Nissan Leaf 8 year

100,000 mile battery warranty

Chevy Volt8 year

100,000 mile battery warranty



WHAT ABOUT THE BATTERY?

When the 8yr, 100k battery warranty expires, howmuch did I save in fuel costs?

Fuel Savings for 100k miles*:

• TOU Rate ~$ 8,000

• Flat Rate ~$7,000

*$2.42/gal used for gas price25 MPG used for Civic

Gas and electric rates fixed in this example.



HOW MUCH TO REPLACE A BATTERY

AFTER 2020?

2011 prices for batteries: $450/kWh*

2014 US DOE goal of: $350/kWh

$275/kWh x 24 = $6,600 estimated 2020 price

(the battery should last beyond 2020 by several years – some cells may require replacement, but not entirepack)

* Deutsch Bank – Vehicle Electrification March 2010



SHOULD BATTERY COST BE THE

CONCERN?

Fuel cost differences are not subtle.



CLOSING REMARKS

§ 9 out of 10 buyers of the Leaf are new to Nissan.

§ Battery prices will come down with volume (remember cellphones?)

§ Charge at night!!

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Electric Cars Dr.Boehm's Presentation