Electric Vehicles: Many Different Kinds
Clean electric vehicles have arrived to help us save the environment and move us closer to energy independence (i.e. not relying on and funding unstable regimes). Understanding if and how much these vehicles contribute towards reducing global warming and increasing energy independence is a complex issue which I have addressed in another place. Here, I want to point out that in order to understand this issue, we first need to understand the different kinds of electric vehicles.
However, before doing that we need to briefly put electric vehicles in perspective relative to gasoline and diesel powered vehicles. Gasoline and diesel are very efficient and inexpensive (relative to other technologies) at powering vehicles. These fuels have collected sunlight over millions of years and have a very high density, and are are in a form which can quickly be delivered to vehicles. It’s hard to beat cheap and dirty energy unless you’re willing to make a compromise. As a result, many alternative technologies which are currently being delivered into the market use smoke and mirrors to hide the fact that they are both more expensive and more dirty than gas/diesel-powered vehicles, while giving the impression that they are exactly the opposite. It’s not unreasonable to use a technology which is more expensive if it’s more clean, but unfortunately we’re paying a premium for something that is also more dirty, without realizing it…sigh. The power grid is dirty. With the current power mix of 70% fossil fuels (50% coal, 20% natural gas, 20% nuclear, 6% hydro, 2% wind, 1% oil, 1% misc) electric vehicles make no sense. However, it makes sense to build up this industry, provided that there is an energy policy to change this mix. Energy policy is the purpose of this blog, but not the purpose of this particular blog entry. This blog entry is focused on understanding the different kinds of vehicles and how they compare relative to each other. What motivated me to write this particular entry, was I attended yet another talk on electric vehicles, and this time I was sold on the feasibility of a hydrogen based vehicle, whereas before I was very skeptical, but I was sold on it for reasons that I didn’t fully understand until just recently. I realized, I’ve run across many different variations on electric vehicles…..time for a blog entry.
Hybrids don’t use the power grid to power the vehicle, but a critical point that is almost universally overlooked is that electric cars must be compared to hybrids, NOT traditional cars. A hybrid already has batteries and an electric motor in addition to the gas motor and has already been demonstrated to be about 2x more efficient than a traditional gas vehicle. The question is whether the electric vehicle is better (i.e. getting rid of the gasoline and the gasoline engine). Hybrids are already a big success despite their increase total cost relative to an equivalent traditional car and the impact of the batteries for a variety of reasons – some people think they’re less expensive because they get higher mpg and they get tax breaks, they are sexy, the environmental impact of batteries is not clearly known and has been largely kept out of the press, and here’s a critical factor: you can use the car pool lane. So is an electric vehicle better?
Pure Electric Vehicle
A pure electric vehicle is currently horrible compared to a hybrid. It’s more expensive, generates more greenhouse gas emissions, and “refueling it” is a pain. In the best case scenario it takes 30 minutes to charge your car to go 100 miles (i.e. at a level 3, high voltage, high current public charging station). That is, if you can find a public charging station, which there are essentially none. You can charge it at home, but this takes 4 – 8 hours, and you’ll have to pay approximately $2K for such a station. But this is a moving target, and some of this will change over time as this industry develops. There will be more public charging stations, and some will be in public garages so you can charge your car while you’re shopping, while at work, and while you’re parked in your parking garage at home if you live in an apartment. The costs will come down as well, but it’s not clear how much. The car will continue to be very dirty unless there is an energy policy at the State or Federal level – and this is possible in the long term. But there is one critical factor that appears to not have the potential to change very much and that is charge time. There is no indication that there is a significant potential to reduce charge times from 30 minutes per 100 miles significantly. There are indications that at best this will improve by about 5% per year. It’s a matter of physics – heat generation, safety, EMF effects, batteries efficiency and life drops with smaller charge times, etc. It’s also not clear how fast the Utility can deploy additional feeds to deliver this kind of power, but let’s assume this can be done.
So in order to analyze this further, imagine that we have an energy policy which brings us to power Utopia; sometime in the future most electric power going to these vehicles is clean and inexpensive. (e.g. Nuclear, Solar Thermal, Wind, maybe Biodiesel power plants). In other words, let’s forget about electric power generation and just focus on the best way to distribute electric power to a vehicle. We still have a problem with charge time. There are several ways to solve this problem:
- Market these vehicles primarily to people who stay mostly in the city or in their local suburb and they can charge these cars at home at night (i.e. they drive less than 30 miles a day).
- Have an infrastructure of public charge stations in shopping malls and at work facilities
- Focus on fleets
- Look into other technologies
One way to solve this problem of “range anxiety” – i.e. not finding a public charging station, or not having the time to wait 30 minutes to charge your car, is to have a hybrid vehicle which you can plug in. So when would you plug it in vs. use the gasoline? In today’s environment, an electric car is less expensive per mile under certain conditions – you charge during off-peak hours, and you already have made the decision to spend the extra money on a hybrid and if a plug-in option is not much more expensive it would make sense. However you would be polluting more if you plugged it in unless we have a clean energy policy, but of course, you might not know that because you think it’s clean, and you might even plug it in even if it’s more expensive and inconvenient because you think it’s clean. Again an energy policy is critical to this equation. But if we have power Utopia, and the electricity actually is clean does this make sense? It would make sense to charge it when at home and at a public charging station and use the gas when you don’t have charging options available. But how many people will do this? Unknown. There is another alternative which I recently found interesting.
This is a confusing topic. Using hydrogen to power cars makes no sense if you view hydrogen as a power source. The same is true of hydrogen fuel cells. Despite what you might hear in the press, hydrogen is not readily available as a power source unless you live on Jupiter or Saturn. It takes energy to get hydrogen out of water – best case scenario, you get out what you put in. Hydrogen is available in natural gas, but this is a fossil fuel. It is also available in various biofuels, but it’s wouldn’t make sense to extract it. However, hydrogen makes sense as an efficient carrier of energy, i.e. a highly efficient and effective alternative to traditional batteries and electric power delivery. So you could use the electricity from our Utopian grid to extract hydrogen out of water, then you could deliver that hydrogen to a car as a liquid much the same as gasoline, and presto you can deliver electric power (indirectly) to your vehicle without the hassle of the 30 minute per 100 mile charge time. Now hydrogen is dangerous, but there are ways to solve this problem which are out of the scope of this blog. Sounds clean, and could actually be very clean, even more so than using batteries – if we had an energy policy.
Electric Car with fuel to power a backup generator
The Chevy Volt does this, and it’s very similar to the way Diesel trains have operated for decades. You run a gasoline or diesel powered engine at optimal RPM’s and generate electricity. It turns out with trains it’s more efficient and easier to control the train to do just this. From a carbon emissions point of view, in the best case scenario (i.e. with technology improvements), you would get about the same efficiency and carbon emissions as a regular hybrid car. So why bother with this technology? In certain conditions it makes sense. If you travel less than 30 miles a day and want a pure electric car, but you have “range anxiety”, you would use the gasoline only when you run out of charge. So why not do the opposite and purchase a plug-in hybrid instead and keep it plugged in, using the gas only as a backup. Well, this kind of car might be less expensive because it doesn’t have a gas engine, but has a gas generator which is arguably less expensive. How this plays out has yet to be determined.
There are other car technologies which are out of scope because they don’t use the power grid. For example Biodiesels, and natural gas powered cars. However, we do need to keep these in mind because they compete with electric vehicles. Natural gas is an interesting story because there is something we can learn from them. They are quite efficient and clean compared to gas powered cars, and are actually relatively safe. Many fleets use these vehicles, so we have evidence that they are effective. Why don’t we see more of them in a consumer market? One of the major reasons is that creating a big enough natural gas infrastructure (e.g. having enough service stations to carry natural gas) carries a significant cost. The economic benefits of natural gas are not significant enough to warrant such a large scale change. There are environmental benefits as they are approximately 50% more clean than gasoline, but that’s not good enough. But it makes sense to apply them to fleets because they typically fuel back at the home base, and there has been much success there because you don’t need to deploy a huge public infrastructure to roll it out, you just need to focus on getting enough fleet customers to justify the cost keeping in mind that they have a benefit to wearing a green badge (because they are in the public’s eye) and in many cases these fleets are government or quasi-government fleets (e.g. Utilities) who can get funding for any extra cost.
This industry is going to evolve dramatically over the next decade with or without an energy policy. An energy policy will make more sense and provide better options. But it depends on the consumer’s true objectives – is it to be green, to feel green, to save money, to contribute towards energy independence, to feel sexy, etc. Each of the above technologies has major drawbacks. For example, Hydrogen is very promising in power Utopia, but requires an enormous investment in infrastructure. The industry will likely evolve from what is practical today. Today hybrids are a big success, so expect plug-in hybrid options to be the next step in the consumer market. Other options are Biodiesels which can be delivered via the diesel fuel infrastructure. Emerging technology with fleets will see a lot of diversity, perhaps hydrogen, perhaps pure electric vehicles, perhaps Biodiesels.
It’s anybody’s guess as to how this will evolve. But if we set our sights on energy policy, the electric power grid has a major role in these technologies, and the sooner we have a volume of vehicles relying on this infrastructure, the sooner we will see more attention paid to energy policy, even if that path is not quite as efficient as we would like it to be.