# Presentation: 798314

## FUELS, FUEL CELL VEHICLES, 

**AND SUSTAINABLE** **FUEL SUPPLY**

- An assessment of
- long-term prospects

- R.H. Borgwardt
- U.S. EPA

- EPA Fuel Cell Workshop
- Cincinnati, OH, June 27, 2001

## ENVIRONMENTAL IMPACT OF A NEW VEHICLE/FUEL SYSTEM

- Depends not only on its tailpipe emissions and public acceptance (and cost) but also on the
- Timing of its introduction
- Proportion of the fleet that can be affected
- Rate at which it can displace the existing system

## VARIABLES THAT AFFECT TIMING, DEGREE, AND RATE OF DISPLACEMENT OF THE EXISTING SYSTEM 

- Availability of biomass as source of fuel
- Availability of platinum for FCV production
- Availability of natural gas as source of hydrogen
- Availability and cost of alternative sources of 			renewable energy (PV, wind)

## CRITICAL METRICS FOR BIOMASS FUELS

- 1.  Land available for biomass production as an energy crop
- 2.  Biomass yield per ha-yr.
- 3.  Amount of biomass economically producible on land 		available for energy crops (including transport cost to 	alcohol plant)
- 4.  Conversion efficiency to alcohol or H2 (GJ basis, including 	biomass production)
- 5.  Cost of conversion to alcohol or H2 (per GJ)
- 6.  End use efficiency of fuel in vehicle (mpge)
- 7.  Fleet displacement potential of alternative fuel/vehicle systems

## ETHANOL BY FERMENTATION OF GRAIN

- Existing production capacity    1855 million gal/y
- Under construction                     134
- Under development                  _1008_
-                    Total ethanol          2997 million gal/y
- 79% of this capacity uses food grains (corn or wheat)
-          (Most of the remainder comes from food wastes)
- Gasoline equivalent of 3000 million gal of ethanol = 1.6% of current U.S. gasoline consumption

## Energy production 			kJ/liter of EtOH

-      ethanol				         21,358
- _Energy consumption_
-     farming operation                                    12,788
-     75% of stalks, cobs, husks                       34,583
-     transportation of field waste                         334
-     other                                                        _      501_
-              *Total consumption                          *48,206
- Energy in / fuel energy out  =  2.25    (Thermal efficiency  =  44%)
- “Net energy production” = (21358 + 34583) / 48206  =  1.16

**Overall Energy Balance for **
**Ethanol Production from Corn**

## NATIONAL BIOENERGY INITIATIVE, May 1999

- PREMISE:
- 4.7 quads bioenergy available by year 2015
- half from agricultural residues
- half from dedicated energy crops
- 31 billion gal ethanol from 4.7 quads biomass
- would reduce U.S. gasoline requirements by 22%
- would reduce oil imports by $10 billion/yr

## ORNL’S BIOMASS SUPPLY CURVES 

**FOR DEDICATED ENERGY CROPS**

- Delivered Cost of biomass = farmgate price + transport cost ($5/mg)

**(Walsh, 1998)**

## NATIONAL BIOENERGY REALITIES

- If achievable, that ethanol would reduce U.S. gasoline requirements by 15%, not 22%
- The minimum production cost of ethanol for NREL’s process is $8.6/GJ which is 48% more than the production cost of reformulated gasoline ($5.8/GJ)
*It would cost $21 billion/yr (min) to produce the  ethanol needed to displace $10 billion/yr of oil imports*

**NATIONAL BIOENERGY REALITIES**

## DEVELOPMENTS AFFECTING PROSPECTS OF FCV FUELS FOR PETROLEUM DISPLACEMENT AND GHG REDUCTION

- Reduced efficiency estimate of FCVs (Thomas et al., 1998):
- H2 = 66 mpge
**	****      ***=2.2 x gasoline ICEV*    (*Was 3.0* x)
- MeOH = 46.1 ± 2.6 mpge
*=1.5 x gasoline ICEV*    (*Was 2.5* x)
- Gasoline, EtOH = 35.9 ± 6.4 mpge
*=1.2 x gasoline ICEV*
- New option for H2:  reforming natural gas at local stations.  (Thomas et al., 2000)

## REASONS FOR REDUCED ESTIMATES

**OF FCV FUEL ECONOMIES**

- The 1995 estimates (Williams et al.) were based only on relative engine efficiency and constant power.
- The new values account for the effect of driving cycle
- power draw and engine efficiency are functions of the driving cycle
- a driving cycle representing realistic average U.S. vehicle operation is now used.
- Fuel economy is a function of vehicle weight.
- FCV drivetrains requiring fuel reformers will weigh 9 - 13% more than ICEV drivetrains.
- FCVs require additional auxiliary power for air compressor, extra cooling fans, humidifier, etc.

## “Widespread use by 2015 of advanced fuel cell technologies for light-duty vehicles could have even more dramatic effect: gasoline requirements would fall by 61 percent”

- “*Widespread use by 2015 of advanced fuel cell technologies for light-duty vehicles could have even more dramatic effect: gasoline requirements would fall by 61 percent*”

## If gasoline requirements were to be reduced by 61%, the fuel economy of FCVs would have to be 2.5 times that of current vehicles

- actual improvement in fuel economy by FCVs fueled with gasoline or ethanol is expected to be no more than 1.2 times the current fuel economy
- gasoline use would fall by 18% (max)
- total hwy fuel use would fall by only 13% (max)

**NATIONAL BIOENERGY REALITY**

## HOW 4.7 QUADS OF BIOMASS MIGHT BE USED AS A SOURCE OF LIQUID FUEL FOR FCVs?

- Conversion Efficiency
- Percentage

- End Use Efficiency
- Percentage

- Gasoline Displaced
- Quads

- Convert to Ethanol
- Convert to Methanol
- Convert to Methanol
- w/ NG

- 49
- 61
- 64

- 120
- 150
- 150

- 2.8
- 4.5
- 16.6

- ______________________________________
**Total current U.S. gasoline consumption  =  17 quads**

## 	  				  End use      Net CO2

- 	  				  End use      Net CO2
-             				  efficiency    reduction,
- 					        %              Kg
- Ethanol from cellulosic biomass               120           1040
- Methanol from cellulosic biomass            150           1390
- Methanol from cellulosic biomass            150           1860
-  plus NG

## Comparison of H2 (from NG) and 

**methanol (from NG + biomass) as FCV fuel**

- _	__	__	__	_	      _H__2_                 _MeOH_
- NG used, mols                                         **62.8                62.8**
- Biomass used, kg                                     **0                     1000**
- CO2 from NG, kg                                     2763               2763
- CO2 from biomass production, kg           0                     155
- CO2 from NG production, kg                  589                 589
- CO2 from imported energy, kg                177                 480
- CO2 from H2 compression, kg                 97                   0
- Gasoline displaced, gal                            **734                 548**
- FCV mpge                                                **66                   46**
- Net CO2 emission reduction, kg              **4400               1860**

## ADVANTAGES OF LOCAL CONVERSION OF NG TO H2 AT REFUELING STATIONS (Thomas et al., 2000)

- Utilize the existing NG distribution system
- One reformer serves thousands of vehicles:
- eliminates need for reformer on each vehicle
- reduces vehicle weight and complexity
- reduces vehicle cost
- increases vehicles fuel economy
- increases reforming efficiency
- reduces capital investment
- - 24 hr stationary operation *vs* 2 hr/day operation on a vehicle
*IS SUFFICIENT SPACE AVAILABLE AT LOCAL STATIONS?*

## For a given amount of domestic biomass and natural gas resources:

- Use of the natural gas alone to produce hydrogen for FCVs will displace more petroleum and achieve greater GHG emission reduction than the use of both biomass and the same amount of NG to produce methanol for FCVs
- And avoids most of the barriers, problems, and objections faced by methanol

**HYDROGEN vs METHANOL**

## FCV FUEL PRODUCTION COST ESTIMATES

- Ethanol from cellulosic biomass             8.6 - 14.3          2.0
- Methanol from cellulosic biomass             12.5                1.7
- Methanol from cellulosic biomass              6.3                 0.85
-     plus natural gas
**Reformulated gasoline                             5.8                1.0**
- Imported methanol (@ $0.30/gal)               5.0                0.67
- Hydrogen from natural gas alone               11.6               1.1
-    (local production from domestic NG)

**FCV FUEL PRODUCTION COST ESTIMATES**

## U.S. natural gas                                   Annual growth,

- _consumption (EIA, 1998)_	    	_EJ/yr_	            _ %     _
- Residential		 		5.43		0.6
- Commercial                       	            3.56		0.7
- Industrial                            	          10.47		1.0
- Electric power                    	 	3.59		4.5
- At current rates of consumption and projected growth, the total U.S. gas reserves will be consumed within 40 years

**U.S. Natural Gas Reserves (GRI, 1998) = 1333 EJ, LHV**

## U.S. Natural Gas Reserves vs. 

**Projected Consumption**

## PLATINUM CONSTRAINT ON

**FUEL-CELL VEHICLE PRODUCTION**

- Fuel: Direct Hydrogen

## DISPLACEMENT OF THE CONVENTIONAL VEHICLE FLEET BY GASOLINE FUEL CELL VEHICLES

- IF U.S. CONSUMPTION OF PLATINUM IS _LIMITED TO 48% OF WORLD PRODUCTION_

## EFFECT OF PLATINUM AVAILABILITY ON RATE OF CONVERSION OF U.S. FLEET TO FCVS

- Fuel

- Pt loading, g/kW

- Time (yr) required conversion of to reach fleet 		80% 	        100%

- Direct H2         0.36                       		   45                     60
- Gasoline          0.72                        		   90                    120
*Key assumptions:   48% of world Pt output consumed for U.S. autos, 98% Pt recycle, Pt production increases 6.5 tonnes/yr**2** from current rate of 155 tonnes/yr, fleet growth at 6.8 million/yr, 15 yr vehicle life*

## FACTORY PRICE OF SOLAR PV MODULES

**AS A FUNCTION OF CUMULATIVE SALES**

- (Cody and Tiedje, 1996)

## HYDROGEN PRODUCTION FROM PV ELECTRICITY

-  	Fleet             H2 production             Net cost of CO2
-       _conversion, %        cost, $/kg        emission avoided, $/tonne_
-                0                        14.4                            603
-                2                          5.9                            198
-               25                         3.1                              73
-               50                         2.5                              47
- Comparable cost of coal-fired power plant (IGCC) using CO2
- sequestration: $72/tonne CO2 emission avoided @ 65% removal

## CONCLUSIONS

- Neither petroleum consumption nor GHG emission from road transport will be significantly reduced by fuels produced from biomass alone
- H2 is the most realistic fuel choice for future road transport in terms of long-term environmental impacts
- Hydrogen-fueled hybrid ICE/electric vehicles need to be considered in addition to FCVs
- Natural gas will be the lowest cost source of H2 but will require import of LNG and use of unconventional sources

## A direct transition to wind and PV as renewable sources of primary energy for H2 production needs to be considered as a sustainable alternative to natural gas

- The costs of electric power from renewable energy sources should be compared with the costs fossil-fueled plants using CO2 sequestration. They should not be compared with existing plants.
- Critical review of all relevant data used by EPA is necessary. There is much internal inconsistency, contradiction, and incompleteness of information in the area of emerging fuels and transportation technology

**CONCLUSIONS**