Are Major U.S. Cities Doomed by Rising Sea Levels?

by Pushan Hinduja

As climate change becomes more and more of a threat, people around the world worry about the fate of US coastal cities that might one day be entirely submerged. Matthew E. Kahn, a visiting professor of economics and spatial science at the University of Southern California argues that these cities shouldn’t worry, as they will adapt and rise above the effects of climate change. Khan begins by citing a Rolling Stone article published in 2013 that predicted Miami, “the nation’s urban fantasy land” turning into an “American Atlantis.” Interestingly enough, this threat is not unique to Miami: the majority of Americans live within 50 miles of an ocean, whether that be in New York, Seattle, San Francisco, or Los Angeles, among many more. An economist by training, Khan argues that based on his understanding of how people invest their money during times of crisis and uncertainty, US coastal cities will successfully adapt to climate change and thus be “just fine.”

To be more specific, coastal city residents and firms are currently all aware that the dangers of rising sea levels are imminent. As a result, there is a huge market incentive for adaptation and the development of innovative solutions to these problems. Additionally, thanks to the “invisible hand,” homeowners will feel the pressure to take self-interest and protect their properties as best as they can to try to maintain value. Khan compares this to the increase in research in the pharmaceutical industry when there is expected demand for a certain drug.

In terms of actual adaptation to the rising sea levels, cities around the US will employ a variety of different tactics, ranging from the upgrading of existing structures to construction of new climate change-resilient structures using modular materials. Khan argues that the rising demand for these new developments will recruit young and new talent into the field, which will lower overhead costs for adaptation, ultimately making the whole system even more sustainable. Another key component of adaptation to climate change is the ability to move to “higher ground.” Khan argues that loss of land due to rising sea levels will not reduce the population in an urban area, because of the ability to retreat and develop on lower risk high ground.

Coastal cities as America’s economic hubs won’t be affected either, as the “physical place” is not what defines an economic hub; instead it is the human capital that clusters in any specific location that makes that place an economic hub. Thus rising sea levels may cause the economic hubs to change locations, perhaps only slightly, but will not negatively harm the U.S. economy.

Ultimately, Khan argues that although rising sea levels due to climate change will play an important role in defining coastal cities in the future, it will not render them underwater wastelands. In fact, US coastal cities will undergo a renaissance of “market-driven adaptation” that will cause both the economy and the population that currently resides in these ‘high threat’ areas to thrive.

Kahn, Matthew E., 2016. Rising Sea Levels Won’t Doom U.S. Coastal Cities. Harvard Business Review.


Demand For Sustainability Drives Tesla To Faux Leather Seats

by Maya Gutierrez

What has caused Tesla to follow other companies in adopting more environmentally friendly options that can decrease their carbon footprint? Diane Cardwell discusses consumers’ increasing demand for more sustainable and animal-friendly materials and its effects on Tesla’s product offerings. She notes an accelerating trend amongst car manufacturers to appear more environmentally conscientious, something people have not traditionally associated with the auto industry. This can be viewed as a response to broader consumer demand for sustainable practices. Just as veganism and its high profile public endorsement by A-list celebrities has driven the food industry and restaurants to cater to the vegan lifestyle, the auto industry now sees value to incorporating sustainable practices in their product offerings. Well-known car companies have already begun to incorporate plant-based products into their cars, but now prospective buyers of Tesla cars, already known as a luxury car brand that has proven eco-friendly does not mean performance-challenged, are demanding that Tesla take their sustainable practices one step further. Continue reading

Just Released! “Energy, Biology, Climate Change”

FrontCover6x9 white border 72dpi EBCC2015

Our newest book, published on May 6, 2015 and available at for $19.95.

The focus of this book is the interactions between energy, ecology, and climate change, as well as a few of the responses of humanity to these interactions. It is not a textbook, but a series of chapters discussing subtopics in which the authors were interested and wished to write about. The basic material is cutting-edge science; technical journal articles published within the last year, selected for their relevance and interest. Each author selected eight or so technical papers representing his or her view of the most interesting current research in the field, and wrote summaries of them in a journalistic style that is free of scientific jargon and understandable by lay readers. This is the sort of science writing that you might encounter in the New York Times, but concentrated in a way intended to give as broad an overview of the chapter topics as possible. None of this research will appear in textbooks for a few years, so there are not many ways that readers without access to a university library can get access to this information.

This book is intended be browsed—choose a chapter topic you like and read the individual sections in any order; each is intended to be largely stand-alone. Reading all of them will give you considerable insight into what climate scientists concerned with energy, ecology, and human effects are up to, and the challenges they face in understanding one of the most disruptive—if not very rapid—event in human history; anthropogenic climate change. The Table of Contents follows: Continue reading

High-Energy Electrode Investigation For Plug-In Hybrid Electric Vehicles

While various high-energy-density electrode materials for lithium-ion (Li-ion) batteries<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–> exist, Lu et al. (2011) suggest that other engineering approaches, such as electrode optimization, be considered to meet the energy requirements for plug-in hybrid<!–[if supportFields]> XE “hybrid” <![endif]–><!–[if supportFields]><![endif]–> electric vehicles (PHEVs). The authors investigate the impact of the electrode thickness on the energy density of Li-ion batteries, although their findings show that the electrode thickness would affect the battery’s “integrity, electrochemical performance, and cycleability.” That is why it is important to find both an appropriate and practical thickness of the electrode for high-energy batteries. The authors also found that the hybrid pulse power characterization (HPPC) test indicates that the electrode resistance is “inversely proportional” to the electrode thickness. This allows for the use of thicker electrodes, practical thickness measuring around 100 µm, in Li-ion batteries to meet standard PHEV power requirements. The authors also find that cycle performance shows that cells with a “higher loading density have a similar capacity retention to cells with a lower loading density.” —Laura Silverberg

Lu et al. assess high-energy electrode density levels for the purpose of meeting the energy requirements for PHEVs. In fiscal year 2009, the Department of Energy (DOE) began its pledge to enable the development of PHEVs with a 40-mile all-electric range. However, along with other challenges regarding Li-ion batteries<!–[if supportFields]>XE “battery” <![endif]–><!–[if supportFields]><![endif]–> in the HEV application, the issue of cycle life, as well as providing sufficient energy within the weight and volume requirements of PHEVs became apparent. Currently, there is no commercially available high-energy material to meet the needs of the proposed 40-mile PHEV. However, this issue can be addressed by engineering approaches. Thus far, various possibilities have been investigated for experimental and modeling techniques including electrode porosity and inactive additives. Both of these possibilities can be utilized to improve the energy density.
Lu et al. examine a series of cathode and anode electrodes with varying thicknesses and porosities that were prepared using a small laboratory coater. Both lithium half-cells and fuel cells were created in an “inert atmosphere glove box with an oxygen level of less than 5 ppm.” Additionally, the results of the electrochemical performance of coin cells, investigated using the HPPC profile, were also used in the study to determine thickness effects.
While no commercially available electrode materials currently exist to meet the weight and volume requirements of a 40-mile PHEV, it is important to consider battery<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–> structure optimization to increase battery energy density, for example, by increasing electrode thickness. Using a battery design model based on PHEV energy requirements, the authors experiment with various cathode and anode electrode thicknesses. They found that the cathode electrode should be thicker than 130 µm if only 70% of the total battery energy will be utilized and that the “battery weight reduction rate levels off when the electrode thickness is greater than 100 µm.” This is due to less weight and volume from the current collector and separator. The authors also evaluate the relationship between the electrode thickness and coating weight before and after calendering. Electrode integrity gets worse when the electrode thickness reaches above 100 µm. Thicker electrodes, however, do not affect the useable capacity of the NCA cathode material at a low cycling rate, although it is affected by the electrode thickness at a higher discharge rate. Due to this, better binder strength must be developed which will allow for thicker electrodes and volume expansion. The authors determine that within the relationship between the deliverable capacity and discharge rate of NCA half-cells, the usable capacity will drop significantly when the discharge rate increases.
Power performance of the NCA half-cells with varying electrode thicknesses also utilized the HPPC test. Area specific impedance (ASI) of the half-cells decreases as the electrode thickness increases and levels off according to the results from the half-cell and full-cell. Lu et al. clarify that “[t]his does not necessarily mean that the cell with the thicker electrode always has a higher power capability,” thus confirming that thicker electrode cells must be discharged at a higher current density. This process can offset the lower impedance. However, this combination can cause tension on the transport of lithium ions in the electrolyte, limiting its rate capability. The last test regards the assessment of capacity fading of cells with various electrode-loading densities. No obvious difference was observed for the full-cells under this condition.
The authors conclude that while the HPPC test results indicate that the electrode impedance is “inversely proportional” to the electrode thickness, this is will allow for good power capability of the Li-ion battery<!–[if supportFields]>XE “battery” <![endif]–><!–[if supportFields]><![endif]–> with a higher loading density in the future. Higher loading densities have similar capacity retention as lower loading densities.

RD&D Cooperation for the Development of Fuel Cell, Hybrid, and Electric Ve-hicles within the International Energy Agency

The rising level of CO2 emissions is becoming more concerning for a growing population dependent on roadway mobility. Fuel cell vehicles, hereafter FCVs, can provide a significant alternative and sustainable form of transport that combines “energy efficiency<!–[if supportFields]> XE “energy efficiency” <![endif]–><!–[if supportFields]><![endif]–>, emissions reductions, and reduced petroleum use.”  This paper summarizes the report of Annex XIII in 2010 by compiling “an up-to date, neutral, and comprehensive assessment of current trends in fuel cell vehicle technology and related policy.” Telias et al. (2010) include a review of the most current components of the fuel cell battery<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–> stack, batteries, and hydrogen storage with commentary on the successful results of fuel cell vehicle demonstrations projects worldwide. —Laura Silverberg
Telias, G., Day, K., Dietrich, P. 2010. RD&D Cooperation for the Development of Fuel Cell, Hybrid, and Electric Vehicles within the International Energy Agency. 2010. World Battery, Hybrid and Fuel Cell Electric Vehicle Symposium & Exhibition, 1–6.

 Telias et al. assess two applications of fuel cell technology, a system that can be seen as a power converter unit providing “electricity and heat and therefore provid[ing] an analogous function in combination with an electric machine as the internal combustion engine<!–[if supportFields]> XE “engine” <![endif]–><!–[if supportFields]><![endif]–> in a conventional vehicle.” The first system functions as an energy converter, used in conjunction with an electric motor to propel the vehicle. The second application of the system analyzes its auxiliary units where power may not be needed at all times, particularly when the vehicle is not in motion. Generally with FCVs, the auxiliaries are significantly lower than that of the demands of the vehicle propulsion.  In both applications of the system, the fuel cell can be directly linked with an electric motor, creating a pure fuel cell power train. It is only when the powertrain is combined with an energy storage system that the powertrain becomes a hybrid<!–[if supportFields]> XE “hybrid” <![endif]–><!–[if supportFields]><![endif]–>. Pure FCVs, systems that can manage with the dynamic power demands of the vehicle, require maximum power; the power demand of the car matches the maximum output power of the fuel cell system. The production of power from the fuel cell system has to react instantaneously since there is no energy storage system within the vehicle. This is dynamic power adaptation. In addition, the fuel cell starting time must be in the same range as an internal combustion engine or battery<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–> electric vehicle. Finally, the power output of a fuel cell system, while temperature-dependent (the power output of the fuel cell may be reduced at a lower temperatures), must not be overly-reduced at the ambient temperatures at which it is expected to operate.
Telias et al. briefly evaluate two configurations of hybrid<!–[if supportFields]> XE “hybrid” <![endif]–><!–[if supportFields]><![endif]–> FCVs. The conventional hybrid contains batteries<!–[if supportFields]>XE “battery” <![endif]–><!–[if supportFields]><![endif]–> that store collected braking energy and supply peaking power, or as an alternative, use a supercapacitor for short-term peak power demands. The plug-in hybrid system can be used with or without a connection to the electricity storage grid—it can be charged from the fuel cell system, or charged with electricity. This allows the user to drive moderate distances using grid-supplied electricity.
FCVs require technologically advanced components that are not found in conventional vehicles today. The major components of a typical FCV include: fuel cell system power electronics (consisting of a fuel cell stack offering significant potential for cost-effective production based on economy of scale, and a motor controller, DC/DC converter, and inverter), fuel processor, current inverters and conditioners, and a heat recovery system), electric machines (use alternating current to provide traction to the wheels of the vehicle, therefore enabling propulsion; an energy storage system, and a hydrogen storage system.
Polymer electrolyte fuel cells, hereafter PEFCs, are typically applied for automotive use. Low-temperature fuel cells show good performance regarding nominal power, cold temperature performance, and service life. High-temperature PEFCs have substantial advantages regarding water management and CO<!–[if supportFields]>XE “CO” <![endif]–><!–[if supportFields]><![endif]–>-tolerance, but function slightly less well under low-temperature conditions. Generally, PEFCs can be operated at low pressure with more simple auxiliaries, which result in less power demand for the air compression. In this scenario, humidity control is needed. In a high-pressure scenario, power density can be increased, allowing the water volume for humidity control to be reduced with the addition of a compressor unit. The majority of FCVs today take advantage of high power, high energy, and long cycle life energy storage devices to improve system performance. These energy storage devices can provide assistance to the fuel cell system during events in which temperature and fuel delivery to the fuel cell stack result in voltage drops during high-load demands. Currently, energy storage systems available for use in FCVs include “lithium-ion, nickel-metal hydride, and lead-acid batteries<!–[if supportFields]>XE “battery” <![endif]–><!–[if supportFields]><![endif]–>, as well as ultra capacitors.” Onboard hydrogen storage systems are also required for FCVs. The development of an onboard system to store hydrogen fuel still remains an inhibiting factor for the widespread commercialization of hydrogen. Research and development of additional technologies is still being conducted.
Worldwide, various FCV demonstration projects have been used as a basis for development of future hydrogen infrastructure performance. These demonstrations offer the opportunity to “gather valuable data—including fuel economy, and other factors—that can be used in working towards creative solutions to technical barriers facing hydrogen fuel cell technology in automobiles.” Telias et al. highlight select results of “notable passenger vehicle demonstrations” from around the world including: North America, the European Union, and Japan. Over the next decade, these project committees will focus on infrastructure development and preparing the market for the introduction of their vehicle models in the transportation sector worldwide. Additionally, the authors assess the international trends in funding for RD&D activities regarding fuel cell and hydrogen technologies for transport applications and the policies that provide the framework of development for these activities. In the United States, the Fuel Cell Technologies Program is responsible for the research and development of: hydrogen production and delivery, hydrogen storage, fuel cell stack components, as well as various aspects of the safety standards, technology, marketing, transportation, and distribution of fuel cells. In the European Union, the Multi-Annual Implementation Plan of the “Fuel Cells and Hydrogen Joint Technology Initiative” is responsible for the research and development of: transport and refueling infrastructure, hydrogen production and distribution, stationary power generation and combined heat and power<!–[if supportFields]> XE “combined heat and power (CHP)” <![endif]–><!–[if supportFields]><![endif]–>, early markets, and cross-cutting issues. In Japan, The “Cool Earth – Innovative Energy Technology Program” gives “priority to 21 technologies based on their potential to reduce CO2emissions and to deliver substantial performance improvement, cost reduction, and increased diffusion as well as technologies where Japan could have the global lead.” In this program, the development for FCVs foresees cost reduction through technology development and improvement of durability and cruising distance over the next decade.

While there has been significant development of battery<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–> electric vehicles and plug-in hybrid<!–[if supportFields]> XE “hybrid” <![endif]–><!–[if supportFields]><![endif]–> electric vehicles, manufacturers are continuing research efforts on FCVs. The list of shortcomings of FCVs has been reduced dramatically, although improvements regarding investment costs of the powertrain and installation of the proper fueling infrastructure need further development. Telias et al. suggest learning from the compressed natural gas infrastructure network for fueling stations or introducing the fuel cell system as a “range extender” in combination with a driving battery plugged or unplugged. While the authors anticipate competition over the technologies of the pure battery electric vehicle and the FCV, the favored outcome of the two systems will be based in its superior “combination of costs and convenience.

A Web-based Light Electric Vehicle for Homecare Use—A Pilot Study

With the rapid increase in biomedical technology, the mortality rate of elderly people in economically developed areas has decreased. However, according to a recent public health survey, problems associated with the aging community in Taiwan have become particularly severe. In this paper, authors Cheng et al. (2010) present an economically viable light electric vehicle design for the homecare of elderly. User needs, application feedbacks, and human factors are taken into account and incorporated into their web-based interactive platform. The goal for this project is to develop a light electric vehicle that can be used for easing the mobility of the elderly both indoors and outdoors. Within their one-year integration project, supported by the National Science Council of TAIWAN, the authors propose and analyze various innovative platforms. These platforms include: “industrial design, biomedical engineering [for healthcare monitoring and vehicle safety checking], mechanical design, power electronics [for green energy development of solar cells], communication technology [for both indoor and outdoor wireless positioning], and information management [regarding computer technology of a built-in health monitoring system].” The authors conclude that their proposed vehicle can provide multiple positive functions for homecare use. —Laura Silverberg
Cheng, K., Liang, T., Lu, C., Shih, D., Cai, D., Hsu, M., Huang, J., 2010. A Web-based Light Electric Vehicle for Homecare Use – A Pilot Study. 2010 International Conference on Computational Aspects of Social Networks, 175–178.

Cheng et al. assess their project from three perspectives: from a technological viewpoint to “build an integration innovation of multiple technologies”; from the industry viewpoint, to “develop an add-on value of the culture electric vehicle for elderly use”; and from the welfare viewpoint, to “promote the humanity of devices.” The project was divided into six research groups focusing on the innovative platforms described above, in order to best develop the proposed light electric vehicle. However, since the research groups are located at varying distant sites, a web-based interactive platform was developed to alleviate discussion and communication problems among the groups. Cheng et al. make note of the importance of collaboration between the varying research groups. In order for one research group to incorporate specific design elements into the light electric vehicle, it is up to another research group to develop that design. This partnership is important for the success of the vehicle.
Industrial design, power control and management, health monitoring and safety checking, information integration, and management are analyzed. Industrial design consists of the survey users’ needs for utilizing the light electric vehicle, the size and design of the vehicle, and the proposal of its conceptual design. The authors provide various views of the proposed light electric vehicle for outdoor use and its detachable chair for indoor use. The authors design a power control and management system to meet the needs of the vehicle. A figure outlining the power supply system is included in the paper. A health monitoring system measuring the ECG signal for vital signs has also been incorporated into the design of the light electric vehicle. Seat pressure and declined level are measured for safety checking. Additionally, a blockdiagram of the system and an image of the developed circuit board that controls the measurement of the ECG signal are provided. The authors integrate a computer screen shot of the management system of the light electric vehicle into their assessment.
The authors conclude that while the interaction information platform may provide a slight solution for communication problems, it is still difficult to discuss the innovative platforms among the participating research groups. However, that is not to say that the future design and implementation of the light electric vehicle is incapable of providing various beneficial functions for homecare use. 

Future Vehicle Society Based on Electric Motor. Capacitor and Wireless Power Supply

Over the past decade, various international conferences on electric vehicles have focused on the discussion of the rise of developing automobile technologies to make the shift from internal combustion engine<!–[if supportFields]> XE “engine” <![endif]–><!–[if supportFields]><![endif]–> vehicles (ICVs) to pure electric vehicles, hereafter EVs. In the future, EVs will be connected to the existing electric powertrain infrastructure, and supercapacitors, rather than conventional batteries<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–>, will function in charging these vehicles. Supercapacitors have a “long operating life, large current density, and environmentally friendly composition.” With this power, EVs powered by supercapacitors can operate for more than twenty minutes, even after a charge of only thirty seconds. In this scenario, the efficiency of these EVs increase, and the recharge time is reduced. Hori discusses a wireless power transfer system based on magnetic resonance and the efficiency in power transfer it enables. Equipped with an electric motor, EVs have three major advantages for traction control systems, antilock braking, motion control, and estimation of road surface conditions: quick and accurate motor torque generation—a motor can be attached to each wheel, and motor torque can be estimated precisely. Hori concludes that EVs that utilize electric motors, supercapcitors, and wireless power transfer, eliminate the need for engines, high performance lithium ion batteries, and large charging stations.—Laura Silverberg
Hori, Yoichi, 2010. Future Vehicle Society Based on Electric Motor, Capacitor and Wireless Power Supply. The 2010 International Power Electronics Conference, 2930–2934.

Hori presents a plug-in hybrid<!–[if supportFields]> XE “hybrid” <![endif]–><!–[if supportFields]><![endif]–> electric vehicle, hereafter PHEV, as the transitional state between ICVs and EVs. With PHEVs, users can utilize nighttime generated electricity during the day and can utilize daytime electricity after a half-day’s charge in the evening. The excess of daytime electricity will prove to be beneficial for electric power companies. Hori hopes that PHEVs will lead to a progressive reduction in gasoline<!–[if supportFields]> XE “gasoline” <![endif]–><!–[if supportFields]><![endif]–> usage and familiarize users with a pure EV lifestyle. By eliminating the requirement of gasoline engines and complex hybrid control systems, the purchase and maintenance costs of the vehicle will be reduced.
As a replacement for conventional batteries<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–>, Hori presents the supercapacitor model, also known as an electric double layer capacitor, hereafter EDLC, as a physical battery needed to run EVs. In comparison to the conventional model, supercapacitors have long operating lives, extremely high power densities, and use environmentally friendly materials in their make-up. The EDLC energy density, on the other hand, is rather low; improvements for increasing energy density will require a significant amount of time. However, that is not to say that the current amount of energy density is insufficient for operating EVs. In fact, when the capacitors utilize anywhere between 50 and 100 Volts, more than 75% of the charged energy can be used. This is not the case for conventional batteries. Additionally, with a short charging time for these capacitors, EDLC-operated EVs can function for longer than twenty minutes on thirty seconds worth of charging. Hori presents the “Capacitor Car,” a concept first utilized by buses in Shanghai, as a suitable and potential transport system for the majority of large cities. Hori details the ubiquity of electric consents and suggests the revamping of vehicle range and infrastructure to apply EV technology to larger scale electric pursuits.
Hori highlights the three main advantages of EVs and the ways in which ICVs are incomparable to their highly sophisticated model: quick torque response of motors, distributed motor installation, and tractable motor torque. The torque response of electric motors is 100 times faster than that of engines. The only energy losses result from the friction between the tire and road surface. With the application of adhesion control, the tire would evade the problem of friction losses. Hori explains that “[t]he most important advantage of these EVs is motion control.” In regard to motor installation, a single EV motor can be “divided into 4 and installed into the wheels of the EV without any significant cost increase, which is not the case with cars.” This is entirely different from conventional 4-wheel drive or 4-wheel steering, which are based on “driving force distribution using differential gear.” Motor torque can be determined from motor current. In EVs, force is transferred from the tire to the road by using “the driving force observer.” Running sensors in the vehicle can inform the driver of road surface conditions, significantly improving driving safety.
Hori proposes a wireless power transfer system for supplying energy to moving objects. In this system, capacitor batteries<!–[if supportFields]> XE “battery” <![endif]–><!–[if supportFields]><![endif]–> will play an important role as a buffer system. This will reduce the dependence on gasoline<!–[if supportFields]> XE “gasoline” <![endif]–><!–[if supportFields]><![endif]–> stations, thereby reducing the costs affiliated with charging gasoline-operated vehicles. Hori mentions the most recent experimental results of wireless power transfer using approximately 10 MHz frequency. The total efficiency of the energy transfer between the two antennas is over 90%. Good robustness of the wireless power transfer system against gap variation and antenna displacement is presented.
Hori mentions that fuel cell vehicles, FCVs, are no longer a viable choice for the future of automobile technology, as they use 100 g Pt per vehicle. Instead, he suggests that FCV vehicle range can be reduced. He concludes that enhancing vehicle technology with the usage of electricity from a power network can revolutionize daily commutation.

Comparative Analysis of Battery Electric, Hydrogen Fuel Cell, and Hybrid Vehicles in a Future Sustainable Road Transport System

With the onset of global warming and climate change, road transport has become responsible for a large part of global anthropogenic emissions of CO2. Today’s road transport, for the most part dependent on oil-derived fuels, generates various pollutants that are harmful to human health. Offer et al. (2010) utilize previous studies conducted by the International Energy Agency, hereafter IEA, on alternative vehicle platforms. One platform called for a reduction of 80gCO2 km-1 to 30gCO2km-1 by the year 2030. The other platform suggested that a substantial shift to hydrogen-fuelled cars by the year 2050 could result in 50% less CO2 emissions. These platforms served as the bases for their comparative analysis of battery electric, hydrogen fuel cell and hybrid vehicles in the years 2010 and 2030. Using data based in technology, cost prediction, and sensitivity analyses of the benefits and drawbacks of alternative fuel-based vehicles, Offer et al. reason that a “combination of electricity and hydrogen as a transport fuel could bring additional benefit to the end user in terms of both capital and running cost.” The authors label this model a hydrogen fuel cell plug-in hybrid vehicle, hereafter FCHEV. While the FCHEV carries a significantly low lifecycle cost in comparison to other alternative fuel-based vehicles, alternate data show the FCHEV’s insensitivity to electricity costs and sensitivity to hydrogen cost. The authors determine that with future technologies, various shortcomings, particularly involving mass-production and infrastructure, could be solved, presenting hydrogen fuel cell and battery electric vehicles as viable options for a future sustainable road transport system by the year 2030. Offer et al. conclude the best platform for future integration of fuel cells is the FCHEV, which, for policy-making purposes, “should be pursued and supported.”—Laura Silverberg

Offer, G.J., Howey, D., Contestabile, M., Clague, R., Brandon, N., 2010. Comparative analysis of battery electric, hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system. Energy Policy 38, 24-29.

 G.J. Offer et al. analyze two of the three “alternative powertrain technologies considered by IEA as viable options of providing a “sustainable road transport system with near-zero emissions” by the year 2030 (IEA, 2008). By taking these into consideration, the authors create their own form of technical, economic and infrastructural comparisons with the analysis of various barriers to the adoption of battery electric vehicles, hereafter BEVs and fuel cell electric vehicles, hereafter FCEVs. For the most part, these barriers are somewhat ‘complementary’, although electricity proves more accessible at this point in time, as electricity is already a widely used energy vector. That is not to say, however, that hydrogen is not a practical option for the future. The authors discuss that overcoming technical and economic barriers are important for large scale, mass-produced adoption of alternative-fuel vehicles; however, their study focuses more on the potential economic advantages of the IEA vehicle platforms. Since the BEV and the FCEV models both rely on an electric powertrain and are otherwise identical, the authors claim that “the two technologies should be considered together rather than separately, in a hybrid solution.”

          Various conclusions can be drawn from the authors’ analysis of alternative-fuel vehicles. In terms of capital costs in the year 2010, FCEVs, BEVs and FCHEVs are all far more expensive than the conventional internal combustion engine, hereafter ICE, powertrain. The ICE powertrain will still be cheaper in 2030, although when lifetime fuel costs are factored in, the overall model proves less efficient. According to the authors’ “optimistic” and “pessimistic” hypotheses for 2030, capital costs could drop significantly, the FCHEV model presenting the lowest capital cost. The authors also discuss that accurate predictions of the future costs of alternative powertrain sources are not possible at this time. Additionally, any mark-up added at the point of sale were not included in the study. This permits the technologies to be evaluated on an equal playing field, representing economic standings during the year 2010. With more development of powertrain technologies and the revising of cost sensitivity trends, these numbers will be reevaluated and relative to the year at hand. Regarding lifecycle costs over 100,000 miles, the authors concluded that FCHEVs appeared to be cheaper than BEVs and exhibited a wider sensitivity to capital and running costs. ICEs and FCEVs lifecycle costs were significantly higher than FCHEVs and BEVs, around 1.75 times greater. The authors conducted a separate study on battery size that considered BEV lifecycle cost sensitivity to battery size. They found that BEV economics are cheapest if a battery size can be reduced to accommodate a range of only 50 miles, predominantly targeting city-based drivers. The authors recommend a battery electric vehicle with fuel cell range extender as the best platform for integration of fuel cells for future road transport. As the most viable option, this model can compete for space in an electrified transport network and allow consumers to choose between recharging or refuelling their vehicle. 

Mobile Source CO2 Mitigation through Smart Growth Development and Vehicle Fleet Hybridization

Current population migration models predict that most U.S. cities will experience the most rapid population growth rates since before the Second World War within the coming decades. Therefore, resources such as clean air, water and constant reliable energy will be significantly strained in these metropolitan areas.  The use of “smart growth” strategies within these cities has been determined to measurably reduce per capita demands for these resources through more compact, mixed-use, and transit-supportive patterns of growth (1704). Also, the improvement of vehicle fuel economy through the use of advanced vehicle technologies such as hydrogen vehicles, hybrid vehicles and plug-in hybrid vehicles is widely accepted as the best approach to reducing urban GHG emissions. However, the universal fusion of advanced technological vehicles into the U.S. transportation sector will take decades due to their high costs and slow vehicle turnover rate. To accommodate such rapid growth, air quality management programs will need to be adopted today to ensure that clean air is provided to the residents of these metropolitan areas of tomorrow. — Blake Kos 
  Stone, B., Mednick, A., Holloway, T., Spak, S., 2009. Mobile Source CO2 Mitigation through Smart Growth Development and Vehicle Fleet Hybridization. Environmental Science & Technology 43, 1704–1710. 

 Stone et al. analyze the results of a study on the effectiveness of reducing emissions of carbon dioxide in various metropolitan areas within the U.S. They have found that significant emission reductions can be met through the incorporation of smart growth development patterns and vehicle hybridization within the whole U.S. transportation sector.
 By 2050, it is expected that populations in large metropolitan areas around the U.S. will drastically increase. The projected rapid population increase will be corresponded with an increase in CO2 emissions from urbanization as well as tailpipe emissions. Many believe that management programs should be adopted to maintain healthy air quality and to control for future climate change effects. This study suggests the potential for both smart growth strategies and technological change within the transportation sector to mitigate GHG emissions growth projected to occur in large cities by 2050. The results indicate that the most aggressive smart growth strategy will reduce current GHG emission trends by 8% while full light duty fleet hybridization will reduce by 18%. Moreover, it has been found that a doubling of population density in these metropolitan areas would be more beneficial than full integration of hybrid technology within the U.S. vehicle fleet. In conclusion, to effectively reduce future urban GHG emissions air quality management strategies should be designed to promote the continued integration of advanced vehicle technologies and to initiate concentrating the new population growth into denser urban centers. In addition to air quality management, cities should develop strategies to address the problems associated with urban growth for example increased traffic congestion and decrease physical activity.

Recent challenges of hydrogen storage technologies for fuel cell vehicles

Quick and reliable personal mobility is one of modern society’s most increasing desires, especially with the progress of a world economy. However, current personal mobility (i.e. automobiles and airplanes) is powered by “dirty” and environmentally harmful sources derived from fossil fuels. Mori et al. (2009) believe that fuel cell technology will address the issues of unhealthy urban air quality and the threat of global warming associated with the current inefficient and environmentally damaging technology. Fuel cell technology is powered by hydrogen, which can be produced from a wide variety of non-fossil sources such as biomass-based production, electrolysis of water as well as natural gas and coal gasification. Unfortunately, fuel cell technology faces an enormous barrier of on-board hydrogen storage before it can be commercially viable and cost-effective for the average consumer. Current state-of-the-art hydrogen storage technology can only store 1/10 of energy of gasoline in the same volume due to hydrogen’s low-density.  In order for a “hydrogen” society to transpire, increased storable hydrogen and efficiency will need to be achieved to have gasoline-comparable driving range. — Blake Kos 
Mori, D., Hirose, K., 2009. Recent challenges of hydrogen storage technologies for fuel cell vehicles. International Journal of Hydrogen Energy 34, 4569–4574.

 Mori and Hirose from the Fuel Cell Development Division of the Toyota Motor Corporation investigate the latest material and system development to solve some of the difficulties of the on-board hydrogen storage. By addressing the on-board storage issue, they believe a hydrogen economy will be a near future possibility and the goal of a cleaner, sustainable and inexpensive energy system will be met.

Hydrogen is expected to be the clean and renewable energy carrier to replace the current dirty and damaging energy source, fossil fuel. Unfortunately, the enormous challenge of on-board hydrogen storage without compromising standard vehicle requirements (i.e. safety, performance, cost, technical adaptation for the infrastructure and scalability) needs to be resolved. To solve this challenge, increases in both storage of hydrogen and efficiency will need to be achieve for a comparable gasoline-powered vehicle range. Researchers have developed a possible solution for extending fuel cell vehicle range. This solution uses a composite high-pressure tank, which is characterized by charge-discharge easiness and a simplified structure. This proposed high-pressured (70 MPa) tank results in 40–50% increases in storage and if coupled with the optimal materials and winding strategies, the tank can result in a 65% increase of storable hydrogen. Hydrogen-absorbing tanks have been determined as another possible solution. These tanks have the advantage of storing about 2.5 times more hydrogen. Also, these tanks have a lower hydrogen weight per tank weight, which makes the vehicle much lighter, thus more efficient. With these proposed, more efficient storage tanks, researchers are on the right track to achieving an on-board storage system that incorporates a lighter tank with increases of storable hydrogen.