Infrastructure Vehicles

Readying an Electrified Transportation System

Investments in public transportation aren’t worth as much if we can’t rely on environmentally friendly power sources.

Earlier this year, Eurostar, which operates trains between London and the European continent, announced that it had met its goal of a 25% reduction in carbon emissions just two years after setting the target for itself. Eurostar, like most high-speed lines, is powered by electric catenary, so it shouldn’t come as a surprise that the majority of its carbon savings came from buying energy from more environmentally friendly power plants. All the company had to do was buy more of its power from France, rather than England, because the former country relies far more on nuclear plants than the latter, whose electricity is largely produced by dirty coal.

Eurostar’s example is a case in point: transportation systems relying on electricity can be dirty or clean, all depending on where the power is coming from. This point is unfortunately lost on most alternative transportation activists, who cite efficiency to support the claimed ecological advantages of using transit instead of automobiles. Yet efficiency means little when the electricity used is being produced by carbon-generating plants.

This problem is especially relevant today in United States, since public transportation in the form of electrified light rail and streetcars is more popular than ever. Freight and long-distance passenger routes, both of which have relied on diesel locomotion for decades, are being considered for conversion to electric operation because of its environmental, efficiency, and capacity advantages. Meanwhile, plans to encourage the use of plug-in hybrids and eventually fully electric automobiles are advancing rapidly. But how will all this electricity be produced?

Today, the majority of U.S. electricity production comes from fossil fuels like oil, natural gas, and coal. Though the latter has the most serious environmental consequences, specifically because of the strip mining required to unearth underground reserves, the use of all three fuels has negative environmental consequences that cause climate change. Light rail running on electricity may seem clean, because the local point emissions — in the city — are nonexistent, especially as compared to diesel-spewing buses. But if the necessary power is being generated at coal-based plants, the global effect is negative, making some transit systems less environmentally sensitive in terms of per passenger emissions than many automobiles.

One feasible solution is to build more nuclear plants in the United States. GOP leadership in Congress is currently pushing against a carbon cap-and-trade bill in favor of the construction of 100 new nuclear facilities. The U.S. currently has 104 operating plants. The Obama Administration is planning to devote $18.5 billion in stimulus funds for the construction of new plants, but Republicans want a lot more pointed towards an industry that hasn’t produced a new facility stateside since the early 1980s. Though the U.S. is the world’s largest producer of nuclear energy, only 20% of total electricity — also the most produced in the world — comes from the source.

The Republican argument against cap-and-trade doesn’t make much since, as the nuclear industry would benefit from its passage, and there’s no reason that the government couldn’t invest in both nuclear power and reduce our dependence on coal and oil. But the party’s advocacy in favor of nuclear power — yet to be replicated by the Democrats — has its merits. France, which relies on nuclear power for 80% of its electricity production, has less than a third of the per capita carbon emissions of the United States. Compared to GDP, France is three times as efficient as the United States; the two nations, which have very similar per capita wealth, produce incredibly divergent amounts of CO2. The use of French TGVs, metros, and tramways releases very little carbon into the atmosphere compared to U.S. systems.

Yet nuclear is no perfect answer to our energy production problems. It takes decades to build new plants, they’re incredibly expensive, and opposition to their construction — mostly based on unfounded fears about public safety — is rampant. Second, the heat nuclear plants release during electricity production is a cause of climate change, too, even though the plants themselves release no carbon. As a result, investment in renewable energy, such as wind and solar, may be the most reliable option, though those options are limited in their capacity and quite subject to changing environmental conditions, which makes their use in non-windy, non-sunny locations less than optimal. To make matters worse, the U.S. electricity grid isn’t good enough to handle shifting huge amounts of power produced by wind in the Plains states or by solar in the Southwest to the more heavily populated coasts. So more environmentally friendly power will have to come from a mix of both nuclear and renewable sources.

The point, then, is that to suggest that transit is ecologically sensitive is more accurate when the source of that transportation’s electricity is carbon-free or at least carbon-reduced. Proponents of transportation alternatives must also be strong advocates of the remaking of our electricity production system.

17 replies on “Readying an Electrified Transportation System”

Good to bring this up, but the actual calculus is WAY more complex than you conclude. For example, your statement “making some transit systems less environmentally sensitive in terms of per passenger emissions than many automobiles.” needs to factor in the efficiency of the power plant, the efficiency of the vehicles the passengers would otherwise be driving, the nature of the driving trip (city traffic, long highway) etc, etc, etc before you could even begin a gCO2/person comparison. Further, the electricity in the grid is not heterogeneous, it comes from diverse sources over diverse geographical areas, so any calculation is only approximate.
I think the important point is that electric transportation (cars, trains, whatever) has the OPPORTUNITY to get progressively cleaner over time as the source energy gets cleaner, something which is not true of gas or diesel. Thus, it is the ideal transitional technology because it can offer both short-term and long-term advantages without requiring unrealistically instantaneous change to a massive new infrastructure, like biofuels, hydrogen or CNG.

“But if the necessary power is being generated at coal-based plants, the global effect is negative, making some transit systems less environmentally sensitive in terms of per passenger emissions than many automobiles.”

So one coal-sourced-electric light rail vehicle carrying on average 60+ people can be worse than 40+ gas-powered cars? Really?

Yes, it seriously matters how the electricity is generated. But there is already a lot more efficiency in transit than in private vehicles, and much more so for electrified rail transit — in terms of number of people per vehicle, amount of friction, and energy generation.

Insisting on squeaky-clean energy for new transit systems from the get-go will likely hamper their progress, and hence be a net loss for the environment.

Biodiesel and ethanol don’t require massive new infrastructure to implement, Rockfish. Metro Transit (Twin Cities) blends biodiesel into their buses in ranges of 2-40% with no problems. Ethanol, in the lower blends, requires no infrastructure.

Also, in concerns of nuclear power, we are well passed peak uranium, and sources are incredibly scarce in large quantities. It is possible that the refining and milling of uranium requires more energy than it produces in fission. Nuclear power is so far and away NOT the answer.

Electrically-powered transportation would have significant benefits for the environment and the economy even if carbon dioxide did not matter.

There is plenty of evidence that oil production has already reached its peak, and even with all the environmentally damaging corn ethanol and expensive liquified natural gas being produced, it is likely that the world will have to start adjusting to using less liquid fuel, and soon. Buses can run on compressed natural gas (which also has gotten much more expensive, and may peak soon), but they will never run on coal, nuclear, solar, wind, hydro or geothermal.

Even if we build a bunch of new coal plants to power the new electric trolleys and freight trains, the reduction in pollution from diesel particulates and toxic products of combustion will be taken off of our streets and concentrated at the power plants, when modern tech makes it possible to clean up most of the emissions. I don’t think we will ever be able to make the CO2 disappear, but coal-generated electricity is cleaner than gas or diesel vehicles in every other way.

Moreover, the increased demand for electricity will make the economics of nuclear and renewables (like wind and solar) more favorable. And High Speed Rail might get a boost if we use the right-of-way for power lines as well.


Look at the fuel efficiency numbers produced by the U.S. Transportation Energy Data Book (in this wiki article):

The average per passenger efficiency equivalent for light and heavy rail was 41 mpg in 2006. A new Prius makes 60+ mpg — for one passenger. The efficiencies aren’t as good as you would think, especially if public transport isn’t filled up. So electricity source really matters.

Biodiesel and ethanol are not a good answer. We can certainly make some fuel from these sources, but even sugarcane and soy (two of the more efficient sources of alcohol and vegetable oil, respectively) take huge amounts of water and land to make a barrel of ethanol or diesel.

Remember, we will have to feed 10 billion people in a few years. Do we really want to devote that much marginably arable land to running our buses, when we could use streetcars or trolleybuses instead? Honestly, I don’t we will have much choice, once petroleum production really starts going downhill.

Personally, I think these energy security issues are the best arguments to get moderates and conservatives to support electrification.

Cameron: Agreed. But the carbon effects of biofuel production are still hotly debated. They do have the possibility of being a major transitional strategy.

Yonah: You make my point for me – who says the people on trains would have been driving Prius’s?! (Also, I would guess the vast majority of US car commuters drive solo, so one passenger stats would apply).
The US light-duty fleet average is barely 25mpg. So transit only has to run 60% full to achieve parity.

Rockfish, you’re understating your case. The 41 mpg figure takes passenger loads into account. The US has unusually low passenger loads by international standards, decreasing fuel efficiency. The same Wikipedia article Yonah quotes says that a Colorado DMU hauling two bilevel coaches can achieve 328 passenger-mpg at 70% load factor, and that Swiss light rail’s energy efficiency per passenger is 37 times that of Amtrak.

Yonah, the French use of nuclear energy is one out of several emission reduction strategies. France’s per capita CO2 emissions are among the lowest in the first world, but in some countries, most notably Switzerland, they’re even lower. Switzerland achieves its low emissions by having a rail system that covers everyone, even in suburban and rural areas.

Cameron, can you provide any support for your claim that we have passed peak uranium? haven’t heard that before, but great! Thorium is a much better fuel than uranium for nuclear reactors:

1) it is much more abundant
2) it can’t be used to make weapons grade materials
3) can be used to safely dispose of weapons grade plutonium
4) It is much safer (the reactors are much more resistant to meltdown)

there are other benefits as well but can’t think of them off the top of my head.

nuclear power is currently the safest & cleanest power source that can be used in large scale currently known to humanity.

Biodiesel & ethanol displace food crops, wind only works when it’s windy. Solar is currently still too expensive, and only works when/where it is sunny.

The idea that nuclear power is dirty or unsafe is completely false and a relic from decades ago when proper safety standards were not well understood.

Lyqwyd, I don’t have a link, but both nuclear power proponents and opponents seem to agree uranium supplies can satisfy current electricity demand for 40 years.

Mind you, 40 years is a good stopgap solution, as the price of solar and wind power drops. Right now solar is still somewhat too expensive – the up-front cost takes I believe 8 years to recoup at current US market prices – but in the future, it’ll be more accessible. Once solar and wind become as cheap as coal and hydro, it’s game over for fossil fuels.

Personally, I think the most promising trend is local, small-scale solar power. Largely because it reduces load on the transmission lines, and does so at peak times. Everyone should have their own solar panel. This will release plenty of hydropower to power transit.

The DoE released a report in 2006 concerning untapped hydroelectric power at existing federal facilities; iirc, the amount of hydropower yet untapped in >1mw capacities per installation in commercially-viable locations amounted to the output of a half-dozen average coal plants. At least one of the projects listed in that report along the Ohio river is being devoloped by a private company, and at more than 10x the DoE estimate.
The us hasn’t yet finished tapping that resource, to say nothing g of other baseline generation such as geothermal.

I’ll agree with Nathaniel up here. Local generation is the key from the individual user. Both Solar, and fuel cells as back up.

There is an issue with this on it increasing prices of commercial power because of reduced demand. But I am a huge believer in nuclear for that. Its safe. its no where near as bad as the treehuggers and jane fonda want you to believe and contrary to the article out of Yale on Monday, they have been building and using floating nuclear reactors for 40 year.

Its a large picture game. We need to spread out generation to each building. We need to electrify every rail line and build more. We need to build more nuclear plants. we need to build more wind/solar/undersea. Its not a one or the other as so many politicians want to make it. We even need higher mileage cars.

But that brings me to another point. There should be a $1000 per year tax on owning a second car in a family. There is really no need. If you live where you need two or more cars or have so much money you own them because you want them, move or pay up.

1. The Conawengo dam on the Susquehanna river has been the primary source of power for the Pennsylvania railroad (later Amtrak) electrification between New York and Washington. Not sure if that’s still true.

2. Electric power is considerably more efficient than diesel, so even if the people are already riding transit, the efficiencies make up for coal as a source. In transportation, anyway, the grid is more efficient than moving “local” power production.

3. A big part of the economics of electrifying rail lines is in simultaneously building out the grid for windmill power. It may be that rail electrification uses the wind power!

Dear lyqwyd,

Your points on thorium are well-taken. But the Peak Uranium theory is well-noted. While 70% of oil, 99% of Gas, and 100% of our Coal come from North America, only

The middle ground I’ve taken on nuclear power is that we should not extend the lifespan of decrepit power plants built in the 1960’s, so that when their contracts to operate expire they not be renewed.

Three other reasons to justify not delving further into nuclear power are the lack of a permanent storage facility, which should be infinitely more controversial than a new plant. The cost and time to build a two new reactor at the Vogtle plant is $14 billion, with a capacity of 2,234 MW ($6.26/MW , plus increasingly expensive operating costs for uranium and transporting, with diesel, nuclear waste).

Wind energy, given by all the states’ potential, can meet 90% of our energy needs. When the wind doesn’t blow in Minnesota, it blows in Texas. A national smart grid will totally solve any inefficiencies in lower renewable power operation. Solar thermal power can be used for baseload electricity.

Concerns about nuclear power are not a relic. It is not directly dirty, but the process of building it is, unless you build a reactor using equipment that runs on biofuels. Or, if you power your uranium mill with wind power. Just look deeper at the money.

Using cornstarch for ethanol is better than making corn syrup or feeding cows (which requires 75 gallons of petroleum/steer). The debate over land use is legitimate in policy, but not in penalizing farmers.

Here is a link on ethanol

By establishing infrastructure and a market for ethanol, it’s making it much easier for cellulosic ethanol to advance. In five years, everyone with a flex fuel or diesel will be in much better fiscal shape than those relying solely on gasoline.

Even “electric” cars are not electrified, and are not going to be as much of a miracle worker, like with hybrids. I’m convinced that electric cars may be something of a distraction from good electrified transit, preferably on rails.

The passenger miles per gallon number for trains depend on two main things … trip speeds, and energy efficiency. If Amtrak diesel services operating at a maximum of 79mph average 39pmpg, electrifying will roughly triple energy efficiency, while at the same time upgrading the corridors to allow 110mph rail paths would increase load factors.

All with existing technology.

Modernize the FRA heavy freight standards that require modern passenger trains to carry extra weight (concrete blocks in the “baggage car” of the Talgo tilt trains in the Pacific Northwest) … and even more energy efficiency gains are available.

The obstacle is not technological, its a failure of political will to address the twin problems of climate chaos and structural economic dependence on energy imports.

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