Biomethane for Transportation:Viking 32 Hybrid Vehicle and the Vander Haak Dairy

Western Washington University

Vehicle Research Institute

Eric Leonhardt

Vehicle Research Institute Background

Why Use Biomethane for Transportation?

Challenges with Biogas

Experience with Viking 32 Hybrid

Future Direction

Questions

Vehicle Research Institute

Eric Leonhardt

• Whitman College, B.A. Economics, 1991• Western Washington University, Vehicle

Research Institute, B.S. Industrial Technology, 1995

• University of Michigan, M.S. Automotive Systems Engineering, 2000

• DaimlerChrysler, CAx Research and Development • Electronic Data Systems, Manufacturing

Consulting and Implementation Services

Why Use Biomethane for Transportation?

Improve economics of the anaerobic digester

Alternate market for gas production

Provide low-cost fuel to consumers, public transportation, or farming equipment

Sufficient fuel quantity

Support low emission vehicles

Reduce dependence imported oil

Digester Economics

Relate electrical energy production to value of CH4gas

1) 1200 cows x 60 ft^3/CH4 per day = 72000 ft^3 day or 3000 ft^3/hour

2) Produce 280 kWh@$ 0.05 = $14 per hour or $336/day

3) Lower heating value of CH4: ~904 BTU/ft^3 with 90% CH4

4) BTU per $: (904 BTU/ft^3 x 3000 ft^3/hour) / ($14/hour)Result: 193,700 BTU/$

Compare with Gasoline at $2.50/gallon (West Coast avg):115,500 BTU/gallon * 1 gallon/$2.50 = 46,200 BTU/$

Roughly 4.2 times more energy per $ for Biomethane(193,700 BTU/$ / 46,200 BTU/$)

Whatcom County Fuel Quantity

• 66,000 cows * 60 ft^3 = 3.96x10^6 ft^3/day CH4

• 3.96x10^6 ft^3 * 904 BTU/ ft^3 =3.58x10^9 BTU • 3.58x10^9 BTU / 115,500 BTU/gal (gasoline)• Result: 30,994 gallons of gasoline equivalent

energy per day• Over 11 million gallons of gasoline equivalent

energy per year

Natural Gas Emissions

Biogas Challenges for Transportation

1. Digester biogas contains ~40% carbon dioxide

2. Biogas contains ~3000 ppm hydrogen sulfide

3. Biomethane must be compressed to 3600 psi to provide sufficient range in vehicle

4. Special fuel system and calibration required for biomethane or natural gas

5. Tank size is four times size of gasoline tank

Solution: Clean Biogas

• Remove CO2

• Remove H2S

• Common Industrial Process– Petroleum Refining– Wastewater Treatment

• South Seattle Waste Water Treatment Facility• Tacoma Waste Water Treatment Facility

Viking 32 Experience

Viking 32 Objectives

Challenge Partnership for a New Generation Vehicle—80 MPG “Family” vehicle

Parallel Hybrid

200 HP

2000 lb curb weight

4 Seats

Carbon Fiber Front Impact Absorber

Viking 32 Features

• Rear Drive: 100 HP Natural Gas Honda Civic 1.7 liter 4 cylinder

• Front Drive: 100 HP Uniq Mobility DC Brushless Motor

• Carbon fiber epoxy body and chassis

• Variable ride height from 6” to 9”

• 50 MPGe with Natural Gas

• 44 MPGe with Biomethane

Biogas Scrubber

Three stage process1) Column of iron chips2) Sodium Hydroxide

10% aqueous solution

3) Desiccant

1.4 scfm pump compressed refined gas to ~1700 psi

Iron chips

Sodium Hydroxide

Desiccant

Results

93.6% CH4

850 ppm H2S

~2000 ft3 Gas Collected

Tour de Sol

Lessons Learned

• Sodium hydroxide is caustic, corrodes metals and equipment

• Process requires replacement of “Drano”

• Must have a renewable process for 24/7 operation

• High gas flow rates require significant gas compression facilities

• Hydrogen Sulfide at 850 ppm is too high

Future Steps

Develop a refining capacity of 7200 ft^3/day or 10% total digester flow

Refine with several techniques: • MEA – monoethanolamine• Polyethylene Glycol • Iron Oxide

• Biological: Thiobacillus with Oxygen

Next Generation

Counter flow

>80 linear feet

24”x 26” base

4” diameter PVC

Modular Units

Bioball media

Goals

• 7200 scf biomethane, ~10% total• 15 ppm Hydrogen Sulfide• 7200 scf * 904 BTU/gal = 6.5 million BTU• Equivalent of 56 gasoline gallons equivalent

per day• At 30 MPGe, 1690 miles (30 cars served)• At 40 MPGe, 2254 miles (41 cars served)• Based on 20k miles/year• At $1.50/gasoline gallon equivalent, adds

$84/day or $30,660 gross per year

Thank you!