Comparing Gasoline, Electric, and Fuel Cell Vehicles

 In Vehicle Research

Overview of Fuel Types

In the early 20th century, vehicles were powered by gasoline and electricity—the (surprisingly common-at-the-time) steam-powered vehicles used gasoline and, later, kerosene as fuels. The electric starter cemented the internal combustion engine (ICE) vehicle (hereafter known as the ICEV) and gasoline as the dominant vehicle configuration, and this dominance became almost complete and lasted nearly a century. The recent introduction of alternative fuel sources, namely the return of electricity (in electric vehicles (EVs)) and the introduction of hydrogen (H2, in fuel cell vehicles), has raised the tantalizing possibility that the century-long monopoly of ICEVs and gasoline will be broken.

However, the electricity/EV and H2/FCV challengers must compete from both a performance and cost standpoint, and the gasoline/ICEV incumbent, with all its associated supporting infrastructure, will not be easy to unseat.

Vehicle Performance

Vehicle performance requirements include acceleration, top speed, range, and refueling/charging times. The challengers meet (and in the case of Tesla EVs, often exceeds) the acceleration and top speed performance of ICEVs. However, the performance of the challengers to ICEVs must be comparable for all the requirements so that the vehicle driver does not experience a loss of utility. The cost of the vehicles is another reason for the lower-than-forecast sales; while the cost of EV and FCV components (the two vehicle types share a considerable amount) has decreased, especially dramatically in the case of the energy storage system (ESS) and fuel cell system (FCS), more cost reductions are necessary. The costs of the three vehicles are dependent upon a number of factors that are outside the scope of this analysis, and the focus will be on performance and utility.

Fueling Infrastructure

From an installed infrastructure standpoint, an enormous amount of capital has been spent creating the gasoline infrastructure that allows gasoline stations to have become ubiquitous, with gasoline stations seemingly on every city corner. The companies involved in developing this infrastructure, especially those in the retail sector with those widespread stations, will have a strong incentive to continue to provide transportation fuel at these locations. These station owners of the centralized refueling model require either throughput of vehicles or high charging/refueling prices to avoid the financial model being compromised.

The three vehicle/fuel pathways will be examined below, with a qualitative analysis of the advantages and disadvantages of each in general, followed by a quantitative analysis of the specific areas that are lacking in the performance of the challengers.

Gasoline

To start, gasoline is incredibly useful as a transportation fuel, if the associated emissions are ignored. Gasoline is very energy dense, so a lot of energy can be stored onboard a vehicle in a small space without a lot of added weight, allowing for vehicle ranges that often provide impressive long-distance range utility. Gasoline can also be transferred quickly, so refueling is done quickly and easily. In 2012, there were 114,533 gasoline stations throughout the U.S. (although this number appears to be decreasing). The average number of dispensers per station in the U.S. is estimated to be 8. This means that there were some 916,000 dispensers, and this installed infrastructure represents a significant incumbency advantage for the gasoline/ICEV paradigm.

However, the associated emissions of ICEVs cannot be ignored. When gasoline is combusted, the produced emissions include CO2, the most important greenhouse gas (GHG), as well as criteria-air contaminants (CACs) that cause local pollution like particulate matter (PM), carbon monoxide (CO), sulfur oxides (SOX), volatile organic compounds (VOCs), and nitrous oxides (NOX). Zero-emission vehicles (ZEVs) powered by electricity or hydrogen are seen as essential tools in the twin efforts to reduce GHGs that contribute to climate change and the CACs that cause significant health problems and toxic urban airsheds.

Electricity

EVs have the advantage of the highest efficiency of the three vehicle types and for urban driving where long range is not a factor, EVs are thus currently the ideal vehicle from an efficiency standpoint. Further, depending on the situation of the EV owner, EVs can often be charged at home (or at work) when the vehicle is not in use, making analogous trips to the gasoline station nearly obsolete. This convenience factor can be a huge EV advantage. Home and work charging currently account for over 90% of EV charging and some EV owners never need to use commercial charging infrastructure. For those that do require commercial charging infrastructure, the number of commercial EVSE units has increased from 541 charging spots in 2010 to over 44,000 throughout the U.S. currently, with an increasing focus on DC fast chargers (DCFCs) to reduce the charge event time. However, it should be noted that most vehicles are parked some 95% of the time, and charging an EV can be a convenient proposition for the vast majority of charging instances for many prospective EV owners.

However, EVs do have disadvantages, such as long charging times (even at the fastest rates) and shorter ranges due to the diminishing returns of added ESS capacity (where weight and cost are added as well). Long charging times mean that an EV that is to be driven imminently that must first be charged results in a loss of utility to the EV owner. This disadvantage is compounded for long-distance trips with multiple charging events required, exacerbated by the shorter range. Finally, many people live in urban areas and do not have access to home charging. Those in this increasingly common situation would have to rely on more expensive, relatively sparse, not always available, and sometimes unreliable commercial charging. The charging disadvantage is, for some people, the only reason needed to dissuade them from purchasing an EV. The ESS is also the least energy dense in comparison to compressed H2 and gasoline, making the range of EVs a challenge to automakers to achieve a balance of long-distance driving utility and cost. These reasons, along with high cost, explain why EV sales in the U.S. account for less than 1% of new vehicles some six years after widespread market introduction in December of 2010.

Hydrogen

FCVs have the intermediate efficiency of the three vehicle types as well as intermediate ESS energy density (in the form of compressed H2). H2 storage technology requires significant improvements to enable high long-distance driving utility, especially in cost. However, in addition to superior energy density and specific energy, degradation due to cycle life and calendar life as in an EV ESS does not occur. Further, FCVs can be refueled using the same centralized refueling paradigm as gasoline (enabling widespread ownership by urban apartment dwellers) and at a rate that is comparable to gasoline (enabling long-distance driving with high utility). It should be noted that H2 stations worldwide are following the SAE J2601 standard, which is a direct contrast with the various and competing standards used in EV charging. However, H2 stations are expensive (at $1M per dispenser), and are currently rare, with only 39 throughout the country (35 in CA, going up to an expected 64 by the end of 2018)xii and are expected to come online relatively slowly. H2 also has yet-to-be-solved production and distribution issues, and as a result, only 2,000 FCVs have been sold in the U.S. since they were introduced to the market in late 2015. However, an argument could be made that FCVs must reduce cost only since the utility of an ICEV driver is not compromised by switching to an FCV while EVs must both reduce cost and increase performance because the driver utility is compromised by switching to an EV.

Do you want to learn more about this topic? Download “The Refueling Wars: A Comparison of Gasoline, Electric, and Fuel Cell Vehicles” report now.

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