Presentation on theme: "Technology to Meet Future FE and GHG Requirements K.G. Duleep Managing Director, EEA An ICF International Company 2009 AASHTO Conference."— Presentation transcript:
Technology to Meet Future FE and GHG Requirements K.G. Duleep Managing Director, EEA An ICF International Company 2009 AASHTO Conference
Business Drivers to 2025 New CAFÉ regulations will require significant increases (~40%) to fuel economy by 2016 from 25 mpg in 2008. Regulations to 2025 are already being discussed and may require another 35 to 40% increase beyond 2016. EPA and ARB are also focusing on GHG emissions which depend on both fuel carbon content and fuel economy. Increased concern over oil imports has resulted in push for alternative fuels and electricity.
Auto-manufacturer Response Due to the recent oil price spike and recession, fuel economy improvement has become an integral part of product plans Only realistic alternative hydrocarbon fuel up to 2025 is ethanol which could supplant 20 to 25 percent of light vehicle fuel by 2025. Most manufacturers embrace hybrids, but have very different opinions on plug-in hybrids and battery electric vehicles. Gaseous fuels including hydrogen have serious hurdles in the marketplace. Diesels may be losing their appeal in a GHG constrained world.
Improving Gasoline Engines Although the gasoline engine has been around for 100+ years, there is still substantial scope for efficiency improvements. One significant problem is that ordinary driving uses only 5 to 15 % of the engines peak power, but peak power is required infrequently Many ideas are available to overcome this problem and valve control devices are one way Another exciting development is the direct injection, turbocharged and downsized engine.
Mid-term Engine Technology Most promising development is cam-less valve actuation which offers potential to reduce throttling loss to near zero, and make Atkinson cycle possible at light load. Cam-less engine will be key enabler for gasoline HCCI in longer term Half cam-less engine will enter production in 2014/2015 in luxury cars with about 15%+ FE improvement at a cost of $500 to $700. More advanced valve strategies may allow mixed mode 2-stroke/ 4-stroke engines by 2020.
Other Technology Weight reduction is possible but quite expensive. Only 5 to 10% may be practical at reasonable cost. Drag and rolling resistance reductions of 10 to 20% can be achieved by 2020. Adding more gears to transmissions (6/7 speed) allows better matching of the engine output to the load. Driving the accessories electrically is more efficient than belt drive, since accessories can be used on-demand. Electric Power Steering and Water Pump are the most effective.
Idle Stop- Start New intelligent starter motor design pre engages engine when stopped, resulting in faster, quieter start, even with 14V system. Electrical system must be upgraded with additional battery to withstand start cycles. System will also require electrical AC drive and transmission pump + hill holder for automatic transmissions. Electrical upgrades will facilitate electric accessories such as power steering and water pump, with additional FE benefit.
Summary of Conventional Technology Potential Overall, the sum of all technologies can lead to a 33 + 3% FE increase by 2016 and possibly, up to 50 + 5 % FE increase by 2025.The inability of manufacturers to change technology rapidly will limit the reduction actually attainable to lower values. Major conclusion is that hybrids and diesels are required to meet the ~40% improvement goal for 2016 and will require a market penetration of 10 to 15% combined at 2008 sales mix. Of course, consumer preference and sales mix changes to 2016 can help or hurt these values.
Types of Hybrids Meeting the 40+% 2016 requirement and future requirements may require relatively rapid transition to electric drive -100% by 2030? A large number of hybrid designs have been unveiled, each with unique attributes. Four types that will be in the US market and span the range of designs Belt drive Alternator Starter (BAS) Crankshaft mounted single motor (IMA) Dual Motor full hybrids (Prius/Escape) Plug-in hybrid vehicles.
Common Attributes of Hybrids Hybrids must fully exploit all synergies with drive train and accessories to provide large improvements in fuel economy. Hybrids provide large fuel economy gains only in stop-and go driving. Benefits deteriorate in very hot/cold weather due to space conditioning needs. Hybrids not suited for cargo hauling or high continuous load operation. Different geographies and densities provide different opportunities for different designs.
Hybrid System Benefits BAS systems using existing 14V electrical system can be cheap but provides limited FC reduction, ~ 15% The Toyota system can be very efficient with FC reduction approaching 45% but has the disadvantages of high price, ~US$5000-7000 One- motor systems of the Honda IMA type could be more cost effective than other types at ~ $3000 while offering significant FC reduction, ~30%. Different manufacturers have very different ideas of what will ultimately succeed. Our assessment is that market share could be over 10% by 2016.
Plug-in Hybrids (PHEV) Definition of PHEV varies on vehicle capability in all- electric mode. Range from 10 to 40 miles on electric drive are being considered. Type, range in (semi) EV mode and battery cost issues dominate technical debate. However, consumer acceptance and likely level of electricity use issues are probably more important than technical issues GHG benefits are currently quite small in the US relative to a hybrid, and de-carbonization of the electric sector needs to occur first.
PHEV Cost The retail price of a battery to the consumer is much higher than the cost of a battery cell quoted in the press and runs to over $1200/ kW-h in 2011/12. At these costs, a mid-size PHEV with a 10 mile range will retail for $5000 more while a 40 mile range will cost $20,000 at retail more than a hybrid. Because the hybrid is already quite efficient, the gas savings are not large and will not pay for the extra cost even in 10 years. The battery may not last that long since the PHEV requires both hybrid and EV functionality.
Electric Vehicles Li-Ion Battery technology has now advanced to the point where 100+ mile range is possible, but cost is still high. A 100 mile range compact car needs about 24 kW-h energy battery which alone costs $25K now. The 100 mile range is an EPA test value; in the real world, with the air-conditioner or heat on, range falls sharply and could be as low as 50 miles Operating costs are low at 2.5 to 3 cents/ mile versus 10 to12 cents/mile for current cars. Battery cost is expected to fall by 30% by 2014, but EVs will still be quite expensive, and consumer payback elusive. Given its other shortcomings, most manufacturers do not anticipate EV market share to be significant to 2020 even with current subsidies of $7500
Alternative Ideas to Sell EV Many ideas have been suggested to lower battery costs or monetize lifetime operating cost reduction. Battery Swap model or battery lease models have been suggested but no model works in the US at current battery cost. (It works in Israel and Denmark due to a very large tax subsidy of ~$20k) One plausible idea is that the batteries can have large residual value at the end of its automotive life to utilities and provide grid backup, but this is still unproven even as a concept. With lower battery costs, higher fuel prices and new ideas, EV sales may take off in the 2020s.
Diesel Issues Unlike a hybrid, the diesels fuel efficiency benefit is more robust across all driving conditions and under load. Terrific low-end torque makes it well suited to cargo hauling and towing. Cost and benefit on cycle comparable to IMA hybrid, but GHG benefit is lower due to higher carbon content of fuel. Meeting future emissions standards may be a difficult problem for the diesel engine. Diesel fuel prices and availability in light duty refueling stations may limit acceptance.
$/Percent FC Reduction: Midsize Car with 25mpg On-road Base 20152025 Conventional Tech35 to 5030 to 40 Advanced Conventional NA50 to 60 IMA Hybrid/ Diesel100- 11075 – 80 Full Hybrid140 – 160100 – 120 PHEV200+~150
Analysis Implications Costs of hybrid, diesel, PHEV and EV per unit of fuel consumption are much higher than those of conventional technology. With increased efficiency from conventional technology, marginal value of HEV,PHEV and diesel keep getting worse. As the developed world embarks on serious conservation, fuel prices cannot be expected to rise significantly by 2030 so consumer incentives continue to drop. Possibility of a consumer and political revolt against excessive conservation may limit regulatory drivers.