We're around 10 days in, and we've had enough time now to form some general observations about the cost.
On the highway, as a pure hybrid, the volt gets around 32 mi/gal. Not bad, and that is a worst-case scenario for a hybrid. This really only impacts us when we go on a long trip, but it is almost 10 mi/gal better than the van, and 5 mi/gal better than the old Passat.
As a pure EV, we seem to be getting just under 2.2 mi/kW-hr. That's spectacularly bad for an EV. The Fit EV (which we have dubbed the Blueberry in a nod to Psych) gets 4 even with my lead foot driving style. Tesla claims 3 for the Model S - even with its ginormous battery. 2.2 mi/kW-hr is just over 70 MPGe.
Chevrolet, in their informational data shown either on the web or in-car, shows a downright obsession with MPG - which they calculate by dividing the odometer reading by the amount of gasoline consumed. They do keep a cumulative kW-hr intake that you can view on a charging detail page, but the prominent placement of MPG seems intended to fool you into believing that electric miles are somehow free.
We live in Santa Clara. We have perhaps the lowest electric rates in California. Even so, the top tier is 10.2 ¢/kW-hr, which is the equivalent of $3.41 per gallon in energy equivalent terms. That's cheap, yes, but hardly "free." Now, granted, some charging stations - like the ones we have at work - are free, but this is going to be the wife's car, and she's likely to do the overwhelming majority of her charging at home.
So what are the final numbers? In terms of money per mile, the Fit EV is 2.55 ¢/mi. The Volt as a pure EV is 4.63 ¢/mi. On the highway, as a hybrid, with $4/gal gas, it's 12.5 ¢/mi. Of course, that's purely the cost of energy, and it assumes all kW-hr are 10.2 ¢ and all gas is $4/gal.
Clearly, "don't believe the hype" would be overstating it. As an EV, the Volt is almost 3 times less expensive per mile than it would be as a hybrid. But I do think that Chevy's pushing straight MPG is a bit disingenuous.
Showing posts with label auto. Show all posts
Showing posts with label auto. Show all posts
Wednesday, December 11, 2013
Tuesday, December 10, 2013
What is the plural for "Hydra?"
There are now two Hydras in the world.
We got my wife a Volt, so we are now a two EV family. And instead of installing a second charging station, I built us a Hydra. We spent a week moving the plug back and forth, but I was always nervous that I'd forget to charge one of the cars. And if it was the Blueberry, that would be a particular problem (that's our name for the Fit EV).
There were no particular surprises, but a couple lessons learned:
1. The new Leviton cables don't have a proximity wire in them. That's not good for Hydras, though they do still work. The new cables are also thicker, so they probably require a CG-17 instead of the 16 from Polycase. I don't know if it was that it is cold tonight or the cables are new, but they're quite stiff.
2. I simply must remember to watch out for protrusions near the edge of the internal panel. Two standoffs wound up colliding and I had to use a Dremell to cut them off.
3. I cut myself stripping the outer jacket. It wouldn't be a Hydra if I didn't bleed making it I guess.
4. I had originally used a right-angle plug for the i2c LCD connector, but that hit a standoff for the LCD, so I had to bend it up.
5. The new box I chose from Polycase has much more room inside, but at the cost of, well, being bigger.
I had intended to take a bunch of pictures to make a tutorial on building a Hydra... but then I got into actually building it and forgot.
We got my wife a Volt, so we are now a two EV family. And instead of installing a second charging station, I built us a Hydra. We spent a week moving the plug back and forth, but I was always nervous that I'd forget to charge one of the cars. And if it was the Blueberry, that would be a particular problem (that's our name for the Fit EV).
There were no particular surprises, but a couple lessons learned:
1. The new Leviton cables don't have a proximity wire in them. That's not good for Hydras, though they do still work. The new cables are also thicker, so they probably require a CG-17 instead of the 16 from Polycase. I don't know if it was that it is cold tonight or the cables are new, but they're quite stiff.
2. I simply must remember to watch out for protrusions near the edge of the internal panel. Two standoffs wound up colliding and I had to use a Dremell to cut them off.
3. I cut myself stripping the outer jacket. It wouldn't be a Hydra if I didn't bleed making it I guess.
4. I had originally used a right-angle plug for the i2c LCD connector, but that hit a standoff for the LCD, so I had to bend it up.
5. The new box I chose from Polycase has much more room inside, but at the cost of, well, being bigger.
I had intended to take a bunch of pictures to make a tutorial on building a Hydra... but then I got into actually building it and forgot.
Sunday, December 1, 2013
Scarlet's new Chevy Volt
Anyone who lives in Santa Clara really ought to have an electric car. Santa Clara's municipal electric utility, Silicon Valley Power has maybe the cheapest rates in the entire state. The upper tier of 10.2 ¢/kW-hr equates to around $3.40 per gallon of gas equivalent. And, of course, an electric car is about 3 times more efficient than a gasoline car.
But unless you buy a Tesla, it's impractical (at least today) for a family to do entirely without gasoline power. So when it came time to trade in Scarlet's car, we looked purely at plug-in hybrids. Unfortunately, that cuts way down on the choices. It amounts to choosing between Chevy, Toyota and Ford. We wound up going with the 2014 Chevrolet Volt. We went with the cheapest model, which was around $7500 (or so) less than the tricked out version.
What we miss with the lower model is some of the new high tech driving stuff, like parking assist, lane departure warning and (I think) radar assisted cruise control and built-in navigation. The Volt does have OnStar assisted turn-by-turn navigation, but the way that works is that they download the directions as a set of GPS waypoints. The car doesn't actually have a map at all. If you go off-route far enough, it tells you that you need to phone home again to get updated routing. It's good in a pinch, but if you want an actual map, you need to use your phone.
I took a trip to San Francisco. Highway driving is where EVs and Hybrids actually don't do so well. 11 kW-hr of electricity took me just under 30 miles at 75 mi/hr, and the gasoline engine was able to get around 32 mi/gal after that. Not bad, and it sets expectations for the occasional road trip. But apart from those road trips, it's quite likely that Scarlet won't use a drop of fuel, and will get more like 3 mi/kW-hr or so (the equivalent of around 100 mi/gal), again, at a "fuel" cost of under $3.50/"gal".
Oddly, the cabin is configured as 4 bucket seats. Where normally you'd be able to squeeze 3 small folks into the back seat, that's not an option here. However, the back seat does come with a center console of a sort, and the hatchback area is opened to the back seat. There's also power outlets for both rows of seats, as well as a power port in a little cubby on top of the dashboard (I guess for standalone GPS units?), and the front also has a USB jack nearby used for connecting to the entertainment system (and, yes, it does charge an iPhone with the Lightning cable). Connected that way, it can also control Pandora running on the phone, which is quite nice. Siri works more or less as you'd expect (via Bluetooth), but you must engage her by using the home button on the phone.
I'm not sure how I feel about OnStar. They can place hands-free phone calls for you, but they charge extra for that, and you're not using your phone to make the call (so I'm not sure what the caller ID shows for the people you call), so we didn't opt for that. You can ask them to send down navigation routes, but there's no map. They also have an emergency response system built-in, so they know when the airbags deploy and stuff like that.
The efficiency displays are slightly disingenuous, since they talk about an overall miles/gallon, which they calculate by dividing the odometer by the amount of actual gasoline used. The implication there is that the electricity you "pour" into the car has no cost, which isn't really accurate. Chevrolet salesmen perpetuate this little bit of faulty arithmetic as well. It's true that (at least today) many public charging stations are free, but that's certainly not the case for charging at home.
The only other gotcha we ran into was that by default the Volt is set for a "charging cable theft alarm." What that means is that if you disconnect the J1772 plug without the key being nearby the car alarm will go off. That happened at 10 PM the first night when I moved the plug to the other car, and I turned that nonsense right the heck off.
Anyway, so far it's going pretty well.
But unless you buy a Tesla, it's impractical (at least today) for a family to do entirely without gasoline power. So when it came time to trade in Scarlet's car, we looked purely at plug-in hybrids. Unfortunately, that cuts way down on the choices. It amounts to choosing between Chevy, Toyota and Ford. We wound up going with the 2014 Chevrolet Volt. We went with the cheapest model, which was around $7500 (or so) less than the tricked out version.
What we miss with the lower model is some of the new high tech driving stuff, like parking assist, lane departure warning and (I think) radar assisted cruise control and built-in navigation. The Volt does have OnStar assisted turn-by-turn navigation, but the way that works is that they download the directions as a set of GPS waypoints. The car doesn't actually have a map at all. If you go off-route far enough, it tells you that you need to phone home again to get updated routing. It's good in a pinch, but if you want an actual map, you need to use your phone.
I took a trip to San Francisco. Highway driving is where EVs and Hybrids actually don't do so well. 11 kW-hr of electricity took me just under 30 miles at 75 mi/hr, and the gasoline engine was able to get around 32 mi/gal after that. Not bad, and it sets expectations for the occasional road trip. But apart from those road trips, it's quite likely that Scarlet won't use a drop of fuel, and will get more like 3 mi/kW-hr or so (the equivalent of around 100 mi/gal), again, at a "fuel" cost of under $3.50/"gal".
Oddly, the cabin is configured as 4 bucket seats. Where normally you'd be able to squeeze 3 small folks into the back seat, that's not an option here. However, the back seat does come with a center console of a sort, and the hatchback area is opened to the back seat. There's also power outlets for both rows of seats, as well as a power port in a little cubby on top of the dashboard (I guess for standalone GPS units?), and the front also has a USB jack nearby used for connecting to the entertainment system (and, yes, it does charge an iPhone with the Lightning cable). Connected that way, it can also control Pandora running on the phone, which is quite nice. Siri works more or less as you'd expect (via Bluetooth), but you must engage her by using the home button on the phone.
I'm not sure how I feel about OnStar. They can place hands-free phone calls for you, but they charge extra for that, and you're not using your phone to make the call (so I'm not sure what the caller ID shows for the people you call), so we didn't opt for that. You can ask them to send down navigation routes, but there's no map. They also have an emergency response system built-in, so they know when the airbags deploy and stuff like that.
The efficiency displays are slightly disingenuous, since they talk about an overall miles/gallon, which they calculate by dividing the odometer by the amount of actual gasoline used. The implication there is that the electricity you "pour" into the car has no cost, which isn't really accurate. Chevrolet salesmen perpetuate this little bit of faulty arithmetic as well. It's true that (at least today) many public charging stations are free, but that's certainly not the case for charging at home.
The only other gotcha we ran into was that by default the Volt is set for a "charging cable theft alarm." What that means is that if you disconnect the J1772 plug without the key being nearby the car alarm will go off. That happened at 10 PM the first night when I moved the plug to the other car, and I turned that nonsense right the heck off.
Anyway, so far it's going pretty well.
Sunday, April 7, 2013
Enter the Honda Fit EV
I've leased a 2013 Honda Fit EV.
I'm not really one for "green" thinking. I've said more than once that I think that most of the things that are supposed to be good for the planet are either foolishly costly or ineffective or both. But if you find a way to save me a dollar, you have my attention.
I've talked about this a bit of Facebook, but I think it's worth adding a bit here about the math.
A gallon of gasoline has 33.4 kW-hr of energy in it.
Silicon Valley Power rates are 8.877¢ per kW-hr for the first 300 kW-hr and 10.205¢ for kW-hrs after that. 300 kW-hr isn't a lot, so let's assume the worst and say that it's the 10.205 rate. If you were to magically turn electricity into gasoline at 100% efficiency, you'd be able to gas up that way for $3.41 per gallon. That's not such a big difference, but it is a pretty good deal. But still, the cost of the energy isn't where the big difference is.
Gasoline car efficiency is traditionally measured in miles per gallon. EVs are measured in either miles per kW-hr or kW-hr per 100 miles. The EPA rates the Fit EV as a combined city/hwy of 29 kW-hr/100mi, or 3.44 mi/kW-hr. Convert that into mpg and you get about 115 MPGe.
Despite that, the Fit EV is almost a muscle car in its ability to launch itself off the line. I'd love to take a day off some day to make a trip up to Sonoma to try the quarter mile (of course, it means stopping in San Francisco to charge up... It's just always an issue). I'm pretty confident it could turn in a sub-15 second time. I'm an unapologetic lead-foot and this car is a downright joy to drive. If you put it in "sport" mode, you get a full 123 horsepower and a healthy 189 ft-lb of torque. That's only a little less than Volkswagen's TDI engine (140 hp and 256 ft-lb of torque, but the torque curve of a diesel engine is far narrower than an electric motor).
Though using electricity is a very efficient way to obtain motive power, it's horrendously slow to deliver it and difficult to store. The 20 kW-hr battery represents the energy in less than 2/3 of a single gallon of gasoline and weighs more than 800 pounds. By contrast, an 18 gallon gasoline tank is 600 kW-hr. If I had a 600 kW-hr battery, I'd be able to go almost 2000 miles between charges.
But even that isn't the big issue. The charger built-in to the car is rated at 6.6 kW. In other words, 6.6 kW-hr per hour. So it takes 3 hours to charge completely from empty. Recharging the mythical 600 kW-hr battery above at that rate would take 90 hours - almost 4 days. Even the CHAdeMO HVDC chargers they have now are 62.5 kW - 10 times faster (though it should be noted that the Fit EV isn't equipped with a CHAdeMO port, and frequent use of high-power charging will decrease battery life long term). But those require 3 phase 480v power feeds. My house has a 200A @ 240V service panel - that's only 48 kW, and that's my whose house.
With these sorts of limitations, EVs are reasonable "second cars." But you can't seriously consider taking one on a road trip. No, not even a Tesla. Tesla's strategy is to deploy so-called "supercharger" stations at strategic locations to enable road trips. They have one at Harris Ranch, one in Bakersfield, as well as in Los Angeles.
I'm sure Elon Musk has thought about this longer than I. But I think this strategy is misplaced for a couple of reasons. Let's use my occasional trips to San Diego as the basis for my argument. The trip is 450 miles and takes a total driving time of about 7 hours. It takes longer than that for the trip because of refueling stops (for the car and the driver). In a gasoline car, I've been known to make it in 8 hours or less. Refueling takes about 15 minutes.
The range of a model S is not particularly relevant unless it doesn't make it between Supercharger stations or unless it can "skip" one (no way). Tesla knows this and placed them strategically along I-5. They say they can charge about half way in half an hour. But half a charge won't get you to the next station.
This strategy will only work if the cars stay rare, which clearly is the opposite of Tesla's goal of selling cars (duh). But setting that aside, the trip to San Diego will require 3 intermediate stops for refueling, which will take around an hour each. So the 8 hour trip is now 11 hours.
No. It's just not going to work.
The only solution to this conundrum is temporary auxiliary power provisioning for long trips. This means one of three things:
- Liquid fuel powered pusher trailers
- Liquid fuel powered generator trailers
- Swappable battery pack trailers
Petroleum powered pusher trailers are actually a fairly mature idea. Many tinkerers out there have taken a front-wheel drive vehicle, chopped off the back half, locked the steering, added a trailer hitch and attached it to an EV.By contrast, the idea of using an engine and generator to power the car isn't so great. Scooting down the highway, the car requires something like 20-30 kW just to maintain highway speed. A 20 kW generator is going to be one heck of a trailer. Still, it has been done before (note, however, that the EV hauling this monster is an SUV).
I think the battery pack trailer has the best long-term prospects. Tesla could replace their supercharger stations with a trailer exchange station. Trading out trailers would take probably less time than filling the tank of a conventional car would. The problem there is that 40 kW-hr of battery weighs a good 800 pounds. That's bound to have an impact on the car's performance. Still, 3 100 mile battery swaps, plus the car's internal 150 mile range (remember, we're talking about a Tesla model S) is the 450 miles of the benchmark trip.
However you decide to provision auxiliary power, I think having it be available for temporary rental for road trips is the way to go. If the APU is petroleum (or methanol) powered, the agency renting it will be on the hook for proper maintenance of the emissions controls. Additionally, a rental fleet can be turned over more quickly as technology improves.
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