I was at this year’s Solarfest this past weekend, and helped present two workshops about electric vehicles. The first one was a panel discussion hosted by Drive Electric Vermont, and the second was a presentation I did, entitled “Electric Vehicles: Beyond the Basics”. I think that my thesis, so to speak, is worth thinking about, so I thought I’d recap the presentation here as a blog post.
The quite-short-version, starting with some basics—
1) Whereas a few years ago there were essentially four mainstream production EV’s, (the Volt, Leaf, Tesla Model S, and the plug-in Prius) there are now about twenty, with many more on the way. The biggest recent news is perhaps BMW’s i3, a $40,000 car that is the most efficient in its class, partly due to its lightweight carbon-fiber cabin. The car has gotten extremely high customer-satisfaction ratings, and has been successful enough that Tesla just announced last week that is would be putting together a “Model 3” that will be quite similar. And, EV’s now encompass far more than just cars. There are electric motorcycles, electric pickup trucks, buses, bikes, scooters, school buses, tractor-trailer trucks, and more.
EV owners’ customer satisfaction has been quite high; the Volt and the Tesla Model S have led Consumer Reports’ rating for the last three years.
2) Adoption rates have been brisk, though not quite as brisk as some predicted in years past. The number of EV’s on the road has roughly doubled each year since 2010, and that trend is expected to continue into the foreseeable future. There are currently about 250,000 EVs on the road today in the U.S., and about 500,000 worldwide. To keep those numbers in perspective, though, EV’s currently make up less than 1% of the cars being sold.
3) Charging infrastructure has grown at an extremely rapid pace, from less than 2,000 public charging stations in the U.S. in 2011, to well over 20,000 today, with many more coming into service daily. This has included a huge rise in the number of DC fast chargers, which can charge a vehicle like a Leaf to about 80% in about 30 minutes. A year ago Vermont had zero of these fast chargers, but today we have six, with more on the way. Further advances in charging technology are also on the way, one being inductive charging, which can charge an EV without a direct connection to the vehicle. As demonstrated by a bus system in operation in Seoul, South Korea, inductive charging systems can also be embedded in roadways and function while the vehicles driving above it are in motion.
4) Most EV’s are powered by lithium-ion batteries, and the price for these batteries has fallen dramatically in the past five years, from well over $1,000 per kwh, to about $500 per kwh today. Prices are expected to continue to drop, partly due to Tesla’s new “Gigafactory”, currently under construction. Tesla’s founder, Elon Musk, has predicted Li-ion battery prices in the $250/kwh range by 2015. (Nissan just announced $270/kwh prices for replacement Leaf battery packs.) Combined with economies of scale as EV production increases, I suspect that EV’s will approach outright cost-parity with gas-mobiles in the decade to come. Research is currently proceeding apace on all manner of battery technology, and these advancements have the potential to disrupt power companies, as well as automobile markets.
5) No battery lasts forever, but indications so far seem to show that EV batteries are exceeding expectations. Battery longevity is strongly influenced by many factors, such as average battery temperature, charging and discharge rates, depth-of-discharge, and the average state-of-charge during storage, and some of these are factors that owners can control. When the capacity of EV battery packs does drop below what is considered usable (typically considered to be 70% of its original capacity), power companies have working prototypes of grid-storage options that utilize used EV battery packs. Then, when EV batteries finally do reach the end of their useful life, virtually 100% of the materials in them can be recycled. Today the market value of lithium is such that it is not currently recovered, though the nickel and cadmium and other metals are. I suspect that this will change in years to come, though world reserves of lithium are quite ample, with the bulk of them in the “ABC Triangle”, an area in Argentina, Bolivia, and Chile. (See article “The Lithium Battery Recycling Challenge”).
6) It is becoming easier and easier to build net-zero homes (post- “Net-Zero is Possible”), but what’s really exciting is that it’s now quite possible to build a home that produces enough power for both the house AND for electric-powered transportation. In fact, I currently know of at least three houses that fall into this category. With building and transportation together making up nearly 90% of U.S. energy use, this is truly an exciting development. And since PV panels operate with DC electricity, as do EV batteries, companies like Honda are working on equipment that allows EVs to charge with DC from PV panels, which avoids the conversion losses incurred by inverters.
7) EV’s have a huge potential role with regard to how sustainable power grids will function in the future. This is sometimes called “Vehicle-to-grid”, or “V2G”. A starting point for this is charging equipment that allows power from an EV to go in two directions, either into the vehicle to charge the battery, or out of the vehicle to power the house or grid. Several companies, including Nissan, already have such products on the market. With such a connection, an EV can serve as backup power during a power outage. Then, when this technology is coupled with smart meters, EV’s can serve a key role in reducing generation costs for power companies. In times of peak demand, a power company could remotely stop EV’s from charging, in order to lower peak demand, or, conversely, turn on chargers to soak up excess generation during off-peak hours. Power companies will likely pay customers for the right to control their chargers and EVs in this way, and several pilot projects are already underway. V2G capability also opens up the possibility that EV owners can charge their cars with cheap off-peak power, and sell this power back to the grid during hours of peak-demand.
8) Now, a bit of an aside, but I’ll come back to EV’s in just a bit—as we get higher and higher penetration rates of renewable power into the grid in the years to come, the nature of electricity pricing will steadily change. In the 1970’s it was thought that nuclear power would make electricity “too cheap to meter”. That did not happen, but it has indeed happened recently due to solar. Germany, with its huge amount of solar and wind production, has already seen wholesale electricity prices on sunny days dip into the negative. As these power production curves shift, it will present challenges to power companies. A visual of these upcoming changes was recently released by California ISO (ISO’s, or “Independent System Operators”, are groups that manage grid-power in particular regions), in the now-infamous “duck graph”—
Proponents of renewable power delight in this graph, seeing steadily decreasing peak energy prices and less fossil-fuel use, whereas skeptics argue just as vehemently that these structural changes in generation will cripple the system. At the very least, the chart does imply (and CA-ISO says as much) that much more flexible conventional generation will be required, such as natural gas plants. (Coal and nuclear plants are notoriously difficult to ramp up and down. This is one of a complicated mix of reasons that Germany, for all of its solar and wind generation, has had difficulty, so far, in actually reducing its carbon emissions.) (Economist article.) The duck graph could also point to a need for more thermal solar plants that can use molten salt to store power into the evening, like the new 280 MW Solana plant in Arizona. (A “middle-of-the-road” take on the “duck graph” here, and for further thoughts on how we might deal with increased renewable power generation, see my post “Cloudy Day Pause”).
But, back to the role of electric vehicles. As these changes in generation occur, how people (or smart grids) can most economically use their EV’s will change. To take the two extremes—today, EV owners who use the grid can charge their vehicles at night, during off-peak hours. As I’ve heard a power company official say, off-peak usage is currently so low that nearly everyone in the U.S. could charge an EV at night, with no increase in the number of generation plants that would be required, and no increase in the number of transmission lines. Now, in a decade or two, perhaps spurred by prices on carbon (post– “A Price for Carbon: Ask and You Shall Receive?” ) , we could see huge levels of renewable generation, and daily electricity prices that are the exact opposite of today’s—near zero in the daytime, and quite high at night. In this case market forces will push EV owners to charge not at night, at home, but during the day, at work. In both situations, the greater the difference between peak and off-peak electricity prices, the more it will pay to develop and implement grid-scale storage, whether such storage uses EV’s or not. The good news, hidden in all of this, is that these market forces will keep daytime prices from going too low, regardless of how much solar is generated, and will keep nighttime prices from going too high, regardless of prices on carbon. Electric vehicles, via V2G systems, could play a key role in this. This role for EV’s is actually a bit hard to imagine today, but eventually there will be millions and millions of EV’s in service. Coupled to the grid with V2G technology while parked, these millions of EV’s will play a key role in our move toward full implementation of renewable power generation, and sustainable systems in general.
9) Lastly, self-driving or autonomous vehicle capability will be coupled with EV’s in ways that could dramatically change in the way we move ourselves from place to place. Autonomous vehicles developed by companies such as Google have already driven over 700,000 miles without direct human control, and are legal in four U.S. states (NV, CA, FL, and MI). By some accounts, self-driving vehicles promise to be dramatically safer, by removing human-error as a cause of accidents. These systems will be implemented gradually, first with things like self-parking cars and adaptive cruise control systems, which could be on the market as soon as 2016. Eventually, however, we will be able to send our cars to retrieve our children from school, or use our smart phones to command our cars to unpark themselves and come retrieve us from the front of some venue, and we will be able to do something other than drive on our commutes to and from work (heaven forbid, work even more?). When all vehicles are self-driven (and likely voice controlled), they will be much lighter, as much of today’s heavy crash-protection aspects will be able to be eliminated. Body panels could be made of lightweight plastics instead of steel, and these lighter vehicles will be far more efficient. Perhaps, with inductive charging built into roadways, EV’s could get by with smaller battery packs, and become lighter still. Autonomous vehicles will also be able to drive themselves at high speeds at quite close distances, and this too results in multiple efficiencies, allowing far more vehicles to use a given road at a given time, and reducing wind drag. Here’s Volvo’s video of an actual road train in Europe (it looks like a breakfast cereal commercial for a second, but it’s not…)—
With these efficiencies from lighter vehicles and less wind drag, and perhaps in-roadway inductive charging, autonomous EV’s might even make high-speed rail obsolete.
Autonomous vehicles might also change our paradigms about personal car ownership. Imagine today’s Zip cars, but where all the vehicles are self-driving EV’s that can go park and charge themselves when not in use. It could be that in the future there will be less and less reason to own your own vehicle—when you need one, you just call one up on your phone and it comes to get you, which would also eliminate parking at your destination. (I suppose taxis do this today, but without drivers to pay, autonomous “taxis” should end up being cheaper.)
So— EV’s are about more than just saving fossil fuel. They do that, and they’re fun and efficient. But what’s really important is the ease at which they can be powered with renewable energy, the roles they will play in our future renewable-energy power grids, and their potential to dramatically change how we move from place to place. In fact, I can’t imagine a future sustainable world without them. We aren’t going back to horses and buggies, and, at the other end, we don’t have cold fusion. But we do have solar panels, and power lines, and wind turbines, and computers, and electric cars. And when we put all of those things that we already have together, we’re going to change the world.
Leslie Science Center image: John Hritz, Flickr Creative Commons at https://www.flickr.com/photos/jhritz/480699585 , image has been cropped.