Navigant Research Blog

Mass Transit Energy Efficiency

— December 15, 2010

Recently, Randal O’Toole, who writes the blog The Antiplanner, wrote that mass transit will never be as energy efficient as personal vehicles due to low ridership. Much of his background data comes from a Victoria Transportation Policy Institute study which uses data from a 2008 study by UC Berkeley that examined the lifecycle emissions and energy inputs of light vehicles, buses, light rail, rapid transit and airplanes.

In preparing to discuss this, I have to admit my knee-jerk reaction was to reject O’Toole’s premise as ridiculous. However, as I dug further into the past studies that he references and the information I’ve reviewed in assembling the Clean Mass Transit report, a lot of what he says has merit, and he makes an interesting point. The fact is that the total energy cost of many forms of mass transit is substantially higher than individual cars on a per vehicle basis.

If we think about this on a very basic level, buses are big. They take a lot of energy to build and move once built; they are also much harder on roads because of their weight. Cars in comparison are small, they take less energy to build and move, and have relatively little impact on the roads. The energy required to dig subway tunnels or move heavy trains is substantially more than a car, as well. Making a train or bus energy efficient is a challenge just from the sheer physics of problem.

Of course, the problem is not that simplistic. The physical size challenge is only one of the inputs. Cars need freeways and have to be parked somewhere, while trains need platforms and tracks. According to the UC Berkeley study, the energy consumed over the life of each type of vehicle is:

While this makes sense, the challenge lies in then extrapolating this to the entire system. Assuming that energy consumption per vehicle would have to be applied to each vehicle in the system, the actual energy used by passenger cars is significantly higher because there are significantly more cars than buses or rapid transit trains. According to the DOT, there are 137,079,843 passenger cars (2008) in the U.S., which would require 183,933,000 TJ of energy over their lifetime, compared to the 850,530 buses and 1,576 eight car, rapid transit trains, each requiring 13,456,660 TJ and 949,474.9 TJ, respectively. Similar results are seen when calculation the total energy usage for all passengers (as opposed to all vehicles).

The UC Berkeley analysis appears to ignore the potential savings in fuel manufacturing and usage by alternative energy cars and buses (hybrids, hydraulic hybrids, etc.).

Bottom line, I disagree with O’Toole’s conclusions that the best way to make public transit more energy efficient is to privatize it (which would have the likely result of shifting more people into passenger cars and therefore increase the overall energy usage). But I do agree that increased ridership is really best source of both energy and emissions savings for mass transit, and perhaps the most difficult to achieve.


Charge Spotting: Determining the Right Mix for Public EV Access

— December 13, 2010

I don’t envy the folks charged with determining where the public charging infrastructure should be installed to support the rollout of plug-in electric vehicles (PEVs). The lucky owners of the first Volts and Leafs that are delivered during the next few weeks and months will primarily rely on home charging, but that will be complemented by public locations.

So far in 2010 we’ve seen many announcements about relationships between the charging equipment (EVSE) vendors and retailers, such as Best Buy and Cracker Barrel restaurants installing charging equipment from Ecotality, NRG Energy selecting AeroVironment as a partner for its charging network in Houston, Sheraton Hotels in Toronto and Montreal getting chargers from Coulomb, and Eaton’s charging equipment being chosen for deployment in South Carolina, to name a few.

But are these type of retail locations really the ideal to enable the early PEV adopters to plug in and maximize their electric driving range? Figuring out where and how many charging stations are sufficient is no easy task. Will PEVs truly be taken for longer rides on major thoroughfares, such as the plans for a charging “corridor” along I-5 in Oregon, or are urban gas stations with chargers that enable Leafs to be charged in mere minutes more likely to get action?

The DOE-sponsored EV Project has assigned the task of figuring out how on how to invest in taxpayer –supported public charging infrastructure to Ecotality, which is also providing the equipment. They are producing reports about expected EV and EVSE penetration for each of the regions, and are incorporating data from traffic patterns, work commuting patterns, historical hybrid-electric data ownership, concentration of business, and other factors. For example, in Oregon, Ecotality estimates that for 2011, there will be two charging stations installed for each PEV sold, but that ratio will drop to 1.3:1 by 2020.

The long term ratio of 1:3 to 1 is slightly higher than Pike Research’s forecast for the U.S. , which we project will be approximately 1.15:1. Approximately 80% of all charging will be accomplished at home because of the convenience and lower cost. PEV owners are likely to use their vehicles for commuting and leisure travel and from close in suburbs and within cities. Most of that can be done with minimal need for public charging.

Charging at places of employ and at park and rides, where suburbanites can park and then take mass transit for the rest of their journeys, are expected to have high utilization rates. Charging facilities at gas stations and suburban retail locations are more likely to be underutilized because they are not central to where people will need to spend a long time to charge, or close to where drivers will be when their vehicle batteries will be sufficiently depleted to warrant a charge. If you live in the suburbs, and go out to shop (and it’s not downtown) you’re probably not more than 20 miles from home, so a lengthy charge isn’t required. Also, one of the conveniences of buying an electric car is not having to go to a gas station, and we don’t see PEVs being used for long trips very often during the next few years.

While having a highly visible public charging infrastructure is an important psychological factor in reducing “range anxiety,” expect some of the chargers we’re hearing about to be largely inactive during the next few years.


Neck Deep in Politics: Why Increasing the Gas Tax Makes Sense but Won’t Happen

— December 6, 2010

Today the President’s deficit reduction commission (National Commission on Fiscal Responsibility and Reform) is due to vote on the recommendation to raise the federal gas tax by 15 cents by 2013. This increase was part of the commission’s draft plan to reduce the deficit by $3.8 trillion, and all the funding raised by this tax increase would be “dedicated to fully fund the transportation trust funds and therefore eliminating the need for further general fund bailouts,” according to co-chairmen Democrat Erskine Bowles and Republican Alan Simpson’s proposal. The transportation trust fund is what pays for roads and bridges, and has been bankrupt requiring infusions from the general fund.

A hike in the federal gas tax is long overdue and likely dead on arrival. Since 1993, the current federal gas tax has been 18.3 cents, which due to inflation has the spending power of closer to 12 cents and is why the trust fund cannot pay for itself. Gas tax proposals in the past have garnered essentially no political support. The new congress is lead by Republicans who vehemently oppose raising taxes, while Democrats, who are more likely to consider some tax increases, oppose regressive taxes paid by everyone including the poor and unemployed. In this political climate, increasing the gas tax seems not just unlikely but almost far-fetched. However, supporters of the gas tax increase can take some solace in support from most economists, environmental scientists, and the U.S. Chamber of Commerce (who almost always opposes taxes as a general rule).

Regardless of the politics, a change in the gas tax is likely the fastest way to promote more environmentally-friendly driving among consumers. I am already on record as opposing the CAFÉ rules because they completely ignore the consumer market. For example, without added economic incentive for even modest fuel-saving solutions (or an outright requirement), products like start-stop systems (micro hybrids) receive a very chilly reception in the U.S. market.

In Europe, there are 27 vehicle models featuring start-stop available, while in the U.S. there are only two. The argument over whether to include start-stop systems becomes an argument about how vehicles are tested for their emissions and fuel economy ratings, rather than a market-based value for the dollar discussion. OEMs are forced to assess whether a 1% gain (or less) in their CAFÉ ruling is worth the extra several hundred dollars in cost. In essence, that cost would just come off their bottom line since the fuel economy gains of start-stop systems will be measured in tens of dollars per year at current gas prices.

But start-stop systems are not the only loser in this battle over fuel taxes. Natural gas, LPG, electric and even some hybrids vehicles (particularly heavy duty trucks) are all forced to rely on tax incentives. At the current price of gas and diesel, many of these vehicles’ upfront costs are high enough that the total ownership cost remains higher than that of a gasoline vehicle.
While a 15 cent gas tax is probably too modest to really have an impact on any of these issues, no added gas tax won’t even bring the much needed extra revenue.


European EV Charging Coming Together While Markets Stay Separate

— December 1, 2010

Europe is rapidly building an EV charging infrastructure that will equal, and in some locations, surpass that of the United States. At an EV charging conference in Munich last month industry folks from across the E.U. detailed the projects that will bring ready access to charging posts in London, Lisbon, Paris, Barcelona, and many other major cities.

London Mayor Boris Johnson has said that his city will have 25,000 charging stations in place by 2015. London already has 1,700 EVs according to Cristiano Marantes, the Low Carbon Networks Development Manager at UK Power Networks. Marantes said the power distribution company (in Europe power generation and distribution companies are separate entities) is deploying sophisticated technology that will use smart meters to feed EV charging data directly into its supervisory control and data acquisition (SCADA) system. Marantes said his company won’t upgrade its network due to the increased demand of EVs before 2016. He also said that, as penetration rises, distribution companies will have to rethink how they design networks to accommodate these mobile loads.

Portugal is building an integrated Mobi.E electric mobility platform that will unify the country. The government mandated that a single technology platform be built for the entire country, so all power companies will utilize one communications system for sharing EV data and for billing rather than dealing with the integration issues that face other nations. Drivers will be able to drive anywhere in the country and use their RFID card and be billed to their home, and all of the information will go to a central data center that power companies can access.

All of the countries with representatives at the conference are planning on providing limited DC fast charging as part of their infrastructure roll out. They are all endorsing the Chademo standard originally developed in Japan. DC chargers are expensive ($25,000-$50,000 installed), but in the Netherlands they’ve found an interesting way of financing a charging spot. A convenience store that is on the route of an electric school shuttle bus has installed a fast charger. Every hour a bus of kids is let out to shop while the bus recharges for 15 minutes, and the kids spend enough on magazines, soda and junk food to cover the cost of the charger.

While the U.S. has a single AC EV charger connector, Europe has several proposed standards, including competing options from Germany, France and Italy, and agreement on a single standard is unlikely. Also, many countries have their own basic wall outlet plug, so a car crossing borders will need to carry adapters. Norway’s THINK is developing a portable charger for its EV, and the company will make variants with plugs for each country where the vehicle will be sold.

It is clear that there is no European market for EVs or charging, but rather many markets that happen to be geographically linked.


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