Click for next page ( 2


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 1
Summary This report by the National Research Council’s (NRC’s) Committee on Review of the U.S. DRIVE Research Program, Phase 4, follows three previous NRC reviews of the FreedomCAR and Fuel Partnership, which was the predeces- sor of the U.S. DRIVE Partnership (NRC, 2005, 2008a, 2010). The U.S. DRIVE (Driving Research and Innovation for Vehicle Efficiency and Energy Sustain- ability) vision, according to the charter of the Partnership, is this: “American consumers have a broad range of affordable personal transportation choices that reduce petroleum consumption and significantly reduce harmful emissions from the transportation sector.” Its mission is as follows: “Accelerate the development of pre-competitive and innovative technologies to enable a full range of effi- cient and clean advanced light-duty vehicles (LDVs), as well as related energy infrastructure” (U.S. DRIVE, 2012). The Partnership focuses on precompetitive research and development (R&D) that can help to accelerate the emergence of advanced technologies to be commercialization-feasible. The guidance for the work of the U.S. DRIVE Partnership and the priority setting and targets for needed research are provided by joint industry/government technical teams. This structure has been demonstrated to be an effective means of identifying high-priority, long-term precompetitive research needs for each technology with which the Partnership is involved. Technical areas in which research and development as well as technology validation programs have been pursued include the following: • Internal combustion engines (ICEs) potentially operating on conven- tional and various alternative fuels, • Automotive fuel cell power systems, • Hydrogen storage systems (especially onboard vehicles), 1

OCR for page 1
2 REVIEW OF THE RESEARCH PROGRAM OF THE U.S. DRIVE PARTNERSHIP • Batteries and other forms of electrochemical energy storage, • Electric propulsion systems, • Hydrogen production and delivery, and • Materials leading to vehicle weight reductions. In each of these technology areas, specific research targets have been estab- lished, although some targets and program emphases are undergoing revision. Program oversight is provided by an Executive Steering Group (ESG), which is not a federal advisory committee. It consists of the U.S. Department of Ener- gy’s (DOE’s) Assistant Secretary for Energy Efficiency and Renewable Energy (EERE) and a vice-presidential-level executive from each of the Partnership companies. The DOE EERE efforts are divided between the Vehicle Technologies Program (VTP) and the Fuel Cell Technologies Program (FCTP). The Partnership collaborates with other DOE offices outside of EERE, as appropriate, and with the U.S. Department of Transportation on safety-related activities. The U.S. DRIVE partners include four automotive companies, five energy companies, two electric power companies, and the Electric Power Research Insti- tute, with the DOE providing the federal leadership. During the past year, several associate-member companies have also been added. The Partnership does not itself conduct or fund R&D, but each partner makes its own decisions regarding the funding and management of its projects. Even though the technologies involved are not all under the U.S. DRIVE umbrella, the potential primary pathways to the long-term goals of significantly reduced petroleum consumption as well as reduced criteria emissions and reduced greenhouse gases (GHGs) for LDVs are as follows: • Improved ICE vehicles coupled with greater use of biofuels and natural gas, with low life-cycle environmental impacts; • A shifting of significant portions of transportation energy from petroleum to the electric grid through the expanded use of plug-in hybrid electric vehicles (PHEVs) and battery electric vehicles (BEVs); and • The possible transition to hydrogen as a transportation fuel utilized in hydrogen fuel cell vehicles (HFCVs). The committee notes that none of these pathways is without issues and none is devoid of promise. The development of biomass feedstocks and of the technologies for conver- sion to transportation fuels is outside the responsibility of U.S. DRIVE. Similarly, the impact on GHG emissions of a broad deployment of PHEVs and BEVs will depend on the deployment of a variety of low-criteria-pollutant and low-GHG- emissions electricity generation technologies, another area that is outside the purview of U.S. DRIVE. However, the transition to hydrogen fuel with low life- cycle GHGs is within the scope of U.S. DRIVE.

OCR for page 1
SUMMARY 3 The scope of this review is to assess the progress in each of the technical areas, to comment on the overall adequacy and balance of the R&D effort, and to make recommendations that will help the Partnership meet its goals (see Chapter 1 for the statement of task for the committee). This Summary provides overall com- ments and a brief discussion of the technical areas covered more completely in the report and presents the committee’s main conclusions and recommendations. OVERALL COMMENTS Adequacy and Balance The three previous NRC reports (NRC, 2005, 2008a, 2010) reviewed fund- ing for the FreedomCAR and Fuel Partnership and the allocation of that funding between hydrogen-related and non-hydrogen-related activities. Generally speak- ing, those reports concluded that the balance between technologies was largely appropriate. However, in the Phase 3 report (NRC, 2010), it was noted that major shifts in emphasis and funding had occurred. It was and is the view of the com- mittee that high-risk, potentially high-payoff R&D is an appropriate expenditure of government resources. However, recent economic conditions influence what the committee and the government consider “appropriate.” It is still believed by the committee that support for precompetitive research on long-term technologies such as the enablers for hydrogen to become a viable transportation fuel and the fuel cell R&D leading to affordable HFCVs is important and should be continued. At the same time, the committee continues to agree that government support for technologies that have impact both in the nearer and the longer terms, especially those that could transfer some of the required transportation energy from petro- leum to biofuels or to the electric grid, is also appropriate. Since the last review, distribution of the Partnership funding has shifted significantly, with the share for hydrogen-related activities having decreased continually from $200 million in fiscal year (FY) 2009 to $104 million in FY 2012. Over the same period, battery R&D funding in the VTP dedicated to U.S. DRIVE rose from $69 million to $90 million, and from $23 million to $31 million for advanced combustion R&D. The committee notes that other vehicle technologies receiving significant funding, such as more efficient elec- trical components and lighter-weight materials, would potentially benefit all future propulsion systems. It is the view of this committee that, based on the current status and pro- jected incremental improvements of existing technologies, none of them yet has the performance attributes and cost to dominate the market and to meet the goal of the large-scale replacement of petroleum use and the reduction of emissions. Therefore, it is appropriate to continue investing resources on the most impact- ful research and not to let resources dwindle so far as to be unable to sustain a critical mass required to support a robust decision on any technology. Thus, it is

OCR for page 1
4 REVIEW OF THE RESEARCH PROGRAM OF THE U.S. DRIVE PARTNERSHIP extremely important to choose both the most appropriate technologies and the right targets for each technology. Progress and Barriers Overall, technical progress since the previous NRC review has been steady, and there is evidence of solid progress in all areas; in some cases, the progress has been impressive. The Partnership is effective in moving toward its goals, and the technical teams have been an effective public-private partnering mechanism. However, equally notable are some of the remaining barriers. Good examples are fuel cells and onboard hydrogen storage. On the one hand, projected mass- manufacturing costs have continued their downward trend for automotive fuel cells at the same time that demonstrated durability has continued to rise. On the other hand, onboard hydrogen storage remains a formidable barrier, with no alternative yet proving to be better than compressed gas. For BEVs and PHEVs, lithium-ion (Li-ion) batteries have made substantial progress and costs are declining, but there are formidable barriers to realizing batteries with the performance and cost attributes that would make these vehicles broadly successful in the U.S. marketplace. In addition to cost and technical performance barriers, there are production and infrastructure barriers that must be resolved (e.g., the need for widespread affordable hydrogen if mass-produced HFCVs are to become a reality, a feedstock and production combination for biofuels that does not compete with food crops, and a low-carbon electric grid). For example, BEVs will require a recharging infrastructure that could likely be accelerated by government involvement. The same is true for a refueling infrastructure for HFCVs and natural gas. Indeed, with- out government involvement, a hydrogen refueling infrastructure is unlikely to be realized—which would greatly limit the acceptance of HFCVs (NRC, 2008b). Program Management and Decision Making As in previous NRC reviews of the FreedomCAR and Fuel Partnership, the committee finds the operation and management of the technical teams, and the integration of the systems analysis functions within those teams, to be exemplary for the most part. However, the application of systems analysis to strategic deci- sion making is lagging, especially concerning alternative pathways to achieving objectives such as reduced U.S. petroleum consumption or GHG emissions. It is not apparent that critical issues being investigated by the technical teams are guided and prioritized by an overall program understanding of the scale and lim- its of these technical improvements and how they affect larger program goals. In addition, the results and implications of systems analyses conducted by the technical teams have crosscutting implications for research direction and goals throughout the program. The potential exists for implicit conflict among the

OCR for page 1
SUMMARY 5 respective goals of the various technical teams. It is imperative that the Partner- ship’s ESG, Joint Operations Group, or other program decision-making groups continually broaden their understanding of these implications and adapt research plans as technology or other critical factors change so as to provide effective overall portfolio management. The Phase 3 report expressed concern that the ESG, charged with overall Partnership guidance, had not met for almost 2 years, leaving an apparent vacuum in the realm of guidance at the senior-leadership level (NRC, 2010, p. 35). The ESG did finally meet for the first time in 4 years, in June 2011, and has scheduled annual meetings starting in October 2012. However, given the pace of relevant developments in both technology and policy, this meeting schedule seems barely adequate to “set high-level technical and management priorities for the Partner- ship” as specified in its charter (U.S. DRIVE, 2012). In summary, the Partner- ship’s two systems analysis teams have done excellent work and have made great progress at the microlevel; nonetheless, although there are signs of improvement, it is still unclear to the committee whether and how this work is being adequately applied at the senior-leadership level within DOE or the Partnership to guide overall Partnership direction. Recommendation S-1 (5-1 in Chapter 5). The Executive Steering Group should be engaged to set targets for the U.S. DRIVE Partnership that are consistent with the objectives of reduced petroleum consumption and GHG emissions, and U.S. DRIVE should conduct an overall review of the Partnership portfolio, both for the adequacy of the R&D effort to achieve the targets and for focus on the mis- sion of supporting longer-term, higher-risk precompetitive activities in all three potential primary pathways. Recommendation S-2 (2-1 in Chapter 2). The U.S. DRIVE Partnership should adopt an explicitly portfolio-based R&D strategy to help DOE to balance the investment among alternative pathways along with the more traditional reviews of the progress of individual pathways. Furthermore, this portfolio-based strategy should be based on overall systems analysis performed by a proactive vehicle systems and analysis technical team and fuel pathway integration technical team. ADVANCED INTERNAL COMBUSTION ENGINES AND EMISSION CONTROLS Advanced combustion and emissions control for ICEs are important because ICEs for transportation systems are going to be the dominant automotive technol- ogy for decades, whether in conventional vehicles, hybrid vehicles, PHEVs, or biofueled or natural gas vehicles. Because a better understanding of the combus- tion process and emissions production can help to overcome a major barrier to more advanced ICEs, this work is important to the country.

OCR for page 1
6 REVIEW OF THE RESEARCH PROGRAM OF THE U.S. DRIVE PARTNERSHIP The advanced combustion and emission control technical team is making progress and doing a good job at maintaining a close and constructive working relationship with the stakeholders within the vehicle and energy community. It is critical for the technical team to maintain this collaboration and to look for ways to make it even stronger. Continued close collaboration between DOE and indus- try is necessary to allow newly developed understandings to transition into the industrial laboratories and for the identification of new areas in which enhanced understanding will be most beneficial. The emergence of natural gas in apparently very large quantities is a factor that must also be considered in future visions of ICEs. Natural gas can be used directly as a fuel, it can be used as the feedstock to produce “drop-in” fuels that can replace gasoline or diesel, or it can be used to produce hydrogen. Indeed, the steam- reforming of natural gas is currently used for most hydrogen production. Natural gas is also used in electricity generation and could play a larger role in the future. Recommendation S-3 (3-2 in Chapter 3). U.S. DRIVE should make an as- sessment of whether natural gas can be an enabler for achieving the advanced combustion modes currently being pursued in its research portfolio. FUEL CELLS Based on the advancements that the automotive companies have made on their hydrogen fuel cell vehicles and assuming that part of these advancements have been due to Partnership efforts, it can be said that significant progress has been made since the NRC Phase 3 report (NRC, 2010). Furthermore, investigations on fundamental issues related to durability and performance have been expanded in scope and have begun to yield insight not only into degradation mechanisms but also in terms of providing guidance for developing next-generation catalysts and electrodes, both of which are necessary to meet the performance and cost targets for fuel cells. Progress has been made in other areas as well, even though budgets have been reduced. It is unclear as to whether increased funding would have yielded additional advancements in the past 3 years, but it is clear that the current budget is having an effect on progress. Fuel cell stack cost and durability are still the two major areas that have not simultaneously met targeted levels. Stack lifetimes have exceeded 50 percent of the targeted 5,000 hours in real-world on-road vehicles. Fuel cell costs for a 500,000-vehicle production level have been projected to have dropped since the last report, from $60 to $70/kW in 2009 to $49/kW in 2011. Further reductions will potentially come over time, as learning from on-road vehicle performance and technologies with reduced platinum loadings are adopted. Advanced catalysts have been and continue to be developed, including platinum-free systems. Such programs have emanated from academia, industry, and, most important, from the national laboratories.

OCR for page 1
SUMMARY 7 Statements by automotive companies in this country as well as by companies in other countries have indicated that vehicles in limited quantities will be placed in predetermined locations, partly gated by the availability of hydrogen refueling facilities, in the 2014-2016 time frame. This activity coincides with the timing of the original technology roadmap of the FreedomCAR and Fuel Partnership whereby in 2015 there would be a commercialization readiness decision. Con- sidering the economic downturn and the budget constraints of late, the vehicle engineering accomplishments attest to the commitment of automotive manufac- turers to fuel cell vehicles and thus to the importance of the Partnership’s enabling R&D. The onset of HFCV deployment is impressive. Recommendation S-4 (3-4 in Chapter 3). The DOE should increase efforts for the cost reduction initiatives for fuel cells taking into account the entire system, including balance of plant. Emerging modeling capabilities should be used for sensitivity analysis and for guiding resource allocation to the areas that will have the greatest impact on performance, endurance, and cost at the system level. ONBOARD HYDROGEN STORAGE Onboard hydrogen storage is a key enabler for HFCVs. The primary focus of the hydrogen storage program is to foster the development and demonstra- tion of commercially viable hydrogen storage technologies for transportation and stationary applications. A specific goal of the program is a vehicle driving range of greater than 300 miles between refuelings while simultaneously meet- ing vehicle packaging, weight, cost, and performance requirements. The program also includes life-cycle issues, energy efficiencies, safety, and the environmental impact of the applied hydrogen storage technologies. The physical storage of hydrogen on vehicles as compressed gas has emerged as the technology path for the early introduction of fuel cell vehicles. The hydro- gen storage capacity using compressed hydrogen gas tanks is performance limit- ing for some vehicle architectures and is expensive, but it will apparently not prevent the introduction of HFCVs into the market. The storage capacity of current high-pressure tanks does not meet the long-term program targets, but it may be adequate for some applications for which the cost can be justified. On the basis of current work being undertaken on high-pressure storage tanks, the committee is optimistic that the cost of hydrogen storage tanks can be reduced in the future through reduced materials and manufacturing costs; however, cost reduction is not likely in the near term. Much research was conducted by the (now phased out) three centers of excel- lence for hydrogen storage. These centers eliminated dozens of possibilities while identifying a few with potential for continued study. Although progress continues to be made in solid-state storage, key characteristics, required to meet targets, have not all been met with any single material. Cost is a significant barrier for

OCR for page 1
8 REVIEW OF THE RESEARCH PROGRAM OF THE U.S. DRIVE PARTNERSHIP all systems. Given the reductions in the hydrogen storage budget, the Partner- ship is not on a path to overcome these barriers. Basic research and generation of new ideas are needed. One example is the need for R&D on liner materials for cryo-compressed hydrogen storage. The discovery and development of materials for effective onboard hydrogen storage involve high-technical-risk R&D not likely to be accomplished without continued research attention and government funding. Recommendation S-5 (3-11 in Chapter 3). The DOE (e.g., the Office of Basic Energy Sciences, the Office of Energy Efficiency and Renewable Energy, the Advanced Research Projects Agency-Energy) should initiate a new program that builds on the excellent progress made to date and expands into fundamentally new hydrogen storage research areas. A critical assessment of prospects for, and barriers to, advanced storage techniques and concepts should form the first part of this initiative. ELECTROCHEMICAL ENERGY STORAGE Improved electrochemical energy storage technologies, especially batteries and ultracapacitors, are critical to the advancement of both the Partnership’s nearer-term and long-term goals: significant improvement in their performance and reduction in costs can result in greater electrification of vehicles. Elec- trochemical energy storage technology is a key enabler for all electric drive vehicles, including hybrid electric vehicles (HEVs), PHEVs, BEVs, and HFCVs. The past decade has seen the commercial development of HEVs, due in part to the already-successful development of high-power batteries sup- ported by U.S. DRIVE through the United States Advanced Battery Consortium (USABC). Partially attributable to over a decade of extensive DOE-funded­ Li-ion battery R&D, this technology is now starting to show tangible com- mercial progress in several high-profile battery BEV and PHEV production programs. Additionally, Li-ion batteries are now also being commercialized in HEVs. U.S. DRIVE programs have helped achieve cost reduction of Li-ion PHEV battery technology, with projections of $650/kWh at production volumes of 100,000 packs per year, and being on track for the $300/kWh target this decade. The lifetime of Li-ion battery technologies has been extended to 10 to 15 years and/or 3,000 to 5,000 deep cycles. Performance, life, and safety targets have been met for HEV batteries, with significant cost reductions allowing them to approach cost targets. Key technical and cost barriers remain. Although costs are approaching targets for HEV applications, costs for BEV batteries are most problematic, exceeding targets by a factor of four or more. BEV batteries also have a serious barrier with respect to gravimetric and volumetric energy density, where a twofold

OCR for page 1
SUMMARY 9 improvement is needed. Safety remains an issue that needs continued diligence, especially with high-energy-density BEV batteries that tend to be volatile in response to abuse. The electrochemical energy storage program is comprehensive and well orga- nized and has achieved tangible success in its mission to develop high-power and high-energy electrochemical storage technology for electric drive vehicles. How- ever, the technical targets for electrochemical energy storage systems are largely outdated and contain some significant inconsistencies and unclear constructions. The Phase 3 review recommended revision of the targets, but the Partnership did not act on this recommendation. Revision of the technical specifications can help direct funded and even unfunded R&D toward the most important issues in a more cost-effective way. Recommendation S-6 (3-13 in Chapter 3). The USABC targets for BEV bat- teries are more than 20 years old and should be revised, as also recommended in the NRC’s Phase 3 review. U.S. DRIVE should also undertake a diligent effort to develop a consistent set of technical targets across the key electric drive vehicle applications. ELECTRIC PROPULSION AND ELECTRICAL SYSTEMS Although modern automobiles are loaded with electrical and electronics com- ponents, from power windows to electronic fuel injection systems, many future automobiles will use electric motors in the driveline. Included will be power elec- tronics and electrically driven accessories such as motor-driven air-conditioning compressors, electric power steering, and “smart” interfaces for battery charging. Vehicles will need higher-temperature semiconductors and/or advanced cooling techniques to minimize component size and weight and to maximize efficiencies. Components must be integrated with other components for lower costs and bet- ter space utilization. All of the above suggests the desirability of better modeling and computational techniques in addition to research for a better understanding of the fundamentals. Major accomplishments in this area are a General Motors (GM) traction system that met all of the Partnership goals for 2010 and all of the goals except for cost for the 2015 targets. Also, a Delphi inverter with a General Electric (GE) motor appears to show higher power density and slightly lower cost, although it is not clear that it met the efficiency targets. Since efficiency, volume, and weight are interrelated, meeting just one target is not sufficient, although it does indicate progress. Several promising initiatives were undertaken in 2011. Significant bar- riers are cost, weight, volume, and efficiency, which the Partnership is effectively addressing. Power electronics and electrical machines have been developed over many years, and now significant improvements are needed. A significant issue that needs to be addressed is a thorough systems analysis to assign targets for

OCR for page 1
10 REVIEW OF THE RESEARCH PROGRAM OF THE U.S. DRIVE PARTNERSHIP efficiency, weight, volume, and cost. Ideally this should include the battery, fuel cell, and internal combustion engine so that the whole system can be optimized. Clearly this would involve separate targets for each type of vehicle, that is, for HEVs, PHEVs, BEVs, and HFCVs. Another issue is the cost and availability of the rare earth materials currently used in permanent-magnet motors. Recommendation S-7 (3-15 in Chapter 3). The U.S. DRIVE Partnership should determine the potential and limitations of designing motors with permanent- magnet materials using less rare earth metal. MATERIALS The challenge to the materials technical team is to generate a cost-neutral 50 percent vehicle weight reduction. This target was unrealistic when set, and it remains unrealistic. A similar conclusion was stated in previous NRC reviews. Nevertheless, weight reduction is a crucial part of any balanced approach to achieving aggressive fuel consumption targets, and it will undoubtedly entail enhanced computational methods and widespread material substitution. The work being performed under the auspices of the Partnership appears to be properly focused on relevant initiatives. However, although these initiatives appear rel- evant, the committee questions whether they all satisfy the criteria of high-risk, precompetitive research judged appropriate for federal involvement. Competition has raged among the steel, aluminum, and composites automotive supply base for many years in an effort to achieve low-cost weight reduction by means of materials substitution, and the aluminum, magnesium, high-strength steel, and composites content of production vehicles has been steadily rising for more than 20 years. Furthermore, numerous vehicle demonstration projects have been conducted in the past, both by materials trade associations and by industry consortia, some of which were sponsored by DOE. Clearly, materials are important for many tech- nologies that are part of the U.S. DRIVE Partnership. Recommendation S-8 (3-18 in Chapter 3). The materials technical team should expand its outreach to the other technical teams to determine the highest-priority collective Partnership needs, and the team should then reassess its research port- folio accordingly. Any necessary reallocation of resources could be enabled by delegating some of the highly competitive metals development work to the private sector. HYDROGEN The Partnership in DOE’s EERE includes the hydrogen production, deliv- ery, and dispensing program and is part of the Fuel Cell Technologies Program (FCTP). The FCTP addresses a variety of means of producing hydrogen in distrib-

OCR for page 1
SUMMARY 11 uted and centralized plants using technologies that can be made available in the short and long term. Even though hydrogen has been somewhat de-emphasized by the Obama administration, there are still three technical teams addressing these issues: the fuel pathway integration technical team, the hydrogen production technical team, and the hydrogen delivery technical team. The hydrogen fuel and vehicle pathway integration effort looks across the supply chain from well (source) to tank. The goals of this effort are to (1) analyze issues associated with production, distribution, and dispensing pathways; (2) provide input on methodologies for setting targets for integrated pathways and pathway components; (3) identify needs and gaps in the hydrogen analysis effort; and (4) enhance communication of analysis parameters and results to improve consistency and transparency. Technology is available to produce and distribute hydrogen commercially, but not as a competitively priced transportation fuel. Research efforts are focused on (1) broadening the options available to produce hydrogen with low GHGs and (2) reducing the cost of distribution and dispensing. The hydrogen production program embodies hydrogen generation from a wide range of energy sources, including natural gas, coal, biological systems, nuclear heat, wind, solar heat, and grid-based electricity; grid-based electric- ity employs several of these sources to varying extents, depending on geo- graphical area. In the short term, when a hydrogen pipeline system is not in place, distributed generation in relatively small plants will be required to supple- ment truck-delivered hydrogen available from existing, large-scale commercial plants. Approaches to hydrogen generation using processes based on commercial experience include coal and biomass gasification and water electrolysis. The DOE had a program, completed in 2009, to improve natural gas reforming. Commercial options now exist to generate hydrogen either in distributed or centralized plants using natural gas. The production of hydrogen from coal and/or biomass offers a relatively mature technology. Reasonable estimates of the timing of vehicular hydrogen demand suggest that hydrogen production from new, large-scale coal and/or bio- mass facilities will not be needed before 2020 (NRC, 2008b). Capital cost is a critical issue with either gasification process. In addition, the cost and availability of carbon sequestration are critical with regard to the use of coal, and feedstock cost and availability are critical with regard to the use of biomass. The Partnership recognizes that water electrolysis may play an important role in the hydrogen infrastructure and is supporting numerous promising elec- trolysis efforts to reduce capital and operating costs. In addition, DOE is pursu- ing the use of wind-generated energy for electrolysis to reduce carbon dioxide emissions. Nuclear energy is also a possible source that would not produce significant amounts of GHGs. The DOE is also investigating several approaches to hydrogen production that are in an early stage of R&D and which have the potential to reduce energy requirements for hydrogen production. They include

OCR for page 1
12 REVIEW OF THE RESEARCH PROGRAM OF THE U.S. DRIVE PARTNERSHIP photoelectrochemical and high-temperature thermal water splitting, and biologi- cal generation. A significant factor in fuel cost is the means for delivering, storing, and dis- pensing hydrogen. In a fully developed hydrogen economy, the postproduction part of the supply system for high-pressure hydrogen will probably cost as much and consume as much energy as production does (NRC/NAE, 2004). In the past 2 years there have been significant achievements in hydrogen pro- duction and distribution. The projected cost of transport by tube trailers has been reduced by 40 to 50 percent. In addition, the feasibility of using electrochemical compression of hydrogen instead of expensive mechanical compression has been established, providing a path for further cost reduction. Recommendation S-9 (4-1 in Chapter 4). The DOE should seek the strategic input of the Executive Steering Group (ESG) of U.S. DRIVE. The ESG could provide advice on all DOE fuel programs potentially critical to providing the fuel technologies needed in order for advanced vehicle technologies to achieve reductions in U.S. petroleum dependence and greenhouse gas emissions, and DOE should subsequently make appropriate program revisions to address user needs to the extent possible. Regardless of the source of hydrogen, it is clear that for there to be the pos- sibility of widespread HFCVs, there must be the availability of hydrogen for refueling. GRID IMPACTS OF ELECTRICITY AS AN ENERGY SOURCE FOR VEHICLES The inclusion of battery electric vehicles and plug-in hybrid electric vehicles in U.S. DRIVE makes it important to consider the impact of such vehicles on the electric grid. Reasonable forecasts of market penetration indicate that the increased national energy demands appear unlikely to challenge the capacity of the U.S. electric grid. However, much evidence suggests that clustering of PHEV and BEV owners could result in local loads that exceed the capacity of local transformers, especially for fast charging during hours of peak electricity use. DOE leadership in close collaboration with current and future providers of electricity will be critical to the timely and effective resolution of these issues. BIOFUELS AND THE PARTNERSHIP Within DOE, the Biomass Program has the responsibility for managing the development and progress for the bulk of the needs for biofuels, including biomass production, feedstock logistics, and biomass conversion to biofuel. Historically DOE focused on end use through the Partnership. This split of focus puts the

OCR for page 1
SUMMARY 13 responsibility for making and delivering biofuels with the Biomass Program, and R&D for the LDV drive train with the Partnership. Starting in 2010 the Biomass Program reduced its ethanol programs and increased its programs for making biofuels that are indistinguishable from petro- leum-based products, sometimes called drop-in fuels, which do not require special ICE technology or distribution systems. These can be produced as gasoline, jet fuel, or diesel-type finished products. Biomass sources include woody biomass and energy crops. Considering a scenario in which the role of ethanol is dimin- ished, a U.S. DRIVE focus on ICE development that can handle drop-in fuels and other biofuels is warranted. NATURAL GAS AND THE PARTNERSHIP Although natural gas and light-duty vehicles using compressed natural gas (CNG) are not part of the U.S. DRIVE effort, R&D on CNG storage tanks and on refueling systems is being addressed by DOE’s Advanced Research Projects Agency-Energy (ARPA-E) in its Methane Opportunities for Vehicular Energy (MOVE) program. Recommendation S-10 (4-7 in Chapter 4). U.S. DRIVE should include the CNG vehicle and possible improvements to its analysis efforts in order to make consistent comparisons across different pathways and to help determine whether CNG vehicles should be part of its ongoing vehicle program. REFERENCES NRC (National Research Council). 2005. Review of the Research Program of the FreedomCAR and Fuel Partnership: First Report. Washington, D.C.: The National Academies Press. NRC. 2008a. Review of the Research Program of the FreedomCAR and Fuel Partnership: Second Report. Washington, D.C.: The National Academies Press. NRC. 2008b. Transitions to Alternative Transportation Technologies—A Focus on Hydrogen. Wash- ington, D.C.: The National Academies Press. NRC. 2010. Review of the Research Program of the FreedomCAR and Fuel Partnership: Third Re- port. Washington, D.C.: The National Academies Press. NRC/NAE (National Research Council/National Academy of Engineering). 2004. The Hydrogen Economy: Opportunities, Costs, Barriers, and R&D Needs. Washington, D.C.: The National Academies Press. U.S. DRIVE. 2012. US DRIVE, Driving Research and Innovation for Vehicle Efficiency and Energy Sustainability. Partnership Plan, February. Washington, D.C.: U.S. Department of Energy.