Twenty Two Months in Our Nissan LEAF
Twenty two months and twenty thousand miles behind us and we still love our Nissan LEAF. No other car that we could have chosen two years ago would have done what this car has done for us. In combination with our home's solar panels, our fuel costs for driving those 20,000 miles have been zero. Yes, ZERO. I know that I've mentioned this in almost every post for the past two years, but I still can't believe it.
The LEAF has been completely reliable and it works well for the majority of the trips that we do. The combination of our LEAF with our Toyota Prius works perfectly for us. We take the LEAF when it has enough charge to make our planned trip, and we take the Prius for other trips, including our long distance trips. But sometimes the Prius is driven for simple convenience, or because my wife chooses to take the Prius because she assumes that I'll want to keep the LEAF at home because it's "my car". It turns out that the LEAF is driven about 60% of our miles. Also, our LEAF lease has a mileage limit of 12,000 miles per year, and we are driving the car 91% of those miles. So we could drive the LEAF a bit more than we are currently, but not significantly more without paying lease mileage penalties. We may try to increase our LEAF trips over the remaining 17 months of our lease. After all, we're paying for them in our lease, and the miles are free of fuel cost.
So, great stuff and a lot of positive thoughts about the LEAF, but what is life with an electric car really like? I want to devote the rest of this post to some real world discussion about the changes that driving electric brings to our lives, and the choices that we need to make, as well as my impressions of the degree of success of the recent EV movement in the US so far.
The LEAF is a Real Car
First of all, I need to tell you that the LEAF is a real car. It is roomy, well appointed, reliable and well equipped, with very good electronic displays, navigation, trip computer and infotainment features. Driving it is every bit as normal as driving any small to medium size family sedan. It accelerates well, in fact better than most cars at traffic lights, because of the electric drive train's instant torque. In the morning, I just unplug the car and get in and drive. It isn't slow like a golf cart. The LEAF keeps up with traffic just fine, including climbing hills. In fact, it's more fun to drive than most cars in its size class. It has a top speed of over 90 mph. So let's forget the notion that modern EVs like the LEAF are far out experiments whose time hasn't yet come, or forced sacrifices in the quality of our daily driving. Don't forget that we've put over 20,000 miles on this car in 22 months. These miles have been driven on daily errands, doctor appointments, family visits, shopping trips and pleasure drives, a full 60% of our driving, or more. If this car was a marginal experiment, it wouldn't have been possible for us to use it for so much of our family's driving.
We Have to Plan our Driving More than with a Gas Car
My planning starts each night, with a decision whether to charge the car or not, and whether to charge it fully or to only 80%, which Nissan calls long battery life charging. When making these decisions, I think about the current state of charge of the LEAF's battery pack and how far I plan to drive the following day. I take into account the number of miles I can drive the LEAF on a fully charged pack. In doing so, I take into account how much range the car has lost due to battery aging, whether the weather is going to be cold enough, or the roads wet, whether there are hills along my planned route, and whether I'll be driving on freeways which will limit my range due to higher speeds.
This planning may sound like a pain, but it becomes routine and it is not a big deal. Since the battery is full each morning, even though the "gas tank" is smaller than the gas tank in an ICE car, I can always drive 60 or 70 miles a day. Considering that our average driving day is about 30 miles, the range is usually no problem.
We Tend to Drive Slower and Use the Heater Less to Maximize Range
Above about 45 mph, the LEAF's driving range drops with increasing speed. If my planned route includes a total of 50 miles or more of freeway driving, even on a fully charged battery, I tend to drive more slowly, between 60 and 65 mph, and in the right hand lanes, in order to make my full round trip. If it is cold out, to drive the same distance, I usually choose to dress warmly and skip using the heater, because the heater on the 2011 and 2012 LEAF uses a lot of battery power. And if it is raining, using the defroster in the 2011/12 LEAF also turns on the air conditioner or heater, which saps range. Improvements in the 2013 LEAF solve these problems. Seat heaters and a steering wheel heater in the 2012 and later models help with creature comfort and they use less power than the main cabin heater. If I'm sure that I'll have plenty of range for my day's driving, I'll drive as fast as I want and use the heater freely.
How does this affect our driving pleasure? Well, I have to be frank and say that I'd rather drive as fast as the other traffic and I'd like to be able to use my heater when I want to. Believe me, this car is certainly fast enough to keep up with and pass other traffic. And with my LEAF festooned with "Electric" badges and my personalized license plate, I hate having to drive it slowly in the right lane of the freeway, essentially affirming for passing drivers the misconception that EVs are slow.
The So-Called "Cost Penalty" of EVs is Often an Illusion
Journalists often try to do a simple cost comparison of an EV or hybrid against an "equivalent" car with a gasoline engine, trying to come up with a timeline to pay off the purchase cost premium of the hybrid. The problem with this exercise for EVs is that an electric version of a similar car often turns out to be a much more satisfying vehicle because of the EV's superior acceleration, better handling due to a lower center of gravity, electronic amenities and smooth, quiet driving experience. So the simple math doesn't apply. An EV should be compared with a more satisfying luxury or sport version of the car, if such a car exists. And when that calculation is done, the supposed cost penalty of the EV can disappear.
Whether a given car is worth the cost to a given purchaser is an individual decision. A BMW 3 Series costs more than a Toyota Camry. They are both four door sedans, and they get similar fuel economy, but most people find value in the engineering, prestige and superior driving experience of the BMW, so the extra cost is worth it to them. When journalists try to peg the additional cost of an EV only upon the savings in fuel and maintenance costs, they are missing the point that the ownership experience of the EV can be very much worth the extra expense to some customers. Beyond lower operational costs and the improved driving experience that I detailed above, other motivators might be a desire to have a fuel source that is domestic, more predictable and free from the control of the oil markets and foreign governments, or a desire to reduce carbon emissions, or an attraction to a more technically interesting vehicle.
Usable Range is Less than Full Battery Charge
"How far can you drive?" That is one of the top three questions that EV drivers always get. Well, like any car, it depends on how fast you drive and how aggressively, whether the roads are wet or whether there are steep hills or overall altitude gain along the route. But for EVs, hills and altitude gain have an even greater effect on fuel mileage, very cold temperatures reduce range, and there is more of an impact if the heater is used. While for ICE cars gas mileage is better at freeway speeds, exactly the opposite is true for EVs. Moderate speeds around 45 mph and dry, flat roads are perfect for EVs, and LEAF drivers in some parts of the country have routinely gotten more than 100 miles of range under these conditions, with new cars and their fresh battery packs.
But can you at least use the full available charge of the battery? Well, technically, yes. But realistically, most people will want to play it safe and look to end the journey with a few miles left, when the LEAF's low charge warnings start sounding off. Nissan has chosen to be conservative in having the battery charge bars disappear and the low charge warnings sound when there are still about ten miles of range left in the battery pack (assuming moderate speeds and temperatures). Also, Nissan recommends that to extend battery life, whenever possible, we should charge to only 80% rather than giving the battery a full charge. And finally, as batteries age, they lose capacity.
So at our usual driving efficiency of an indicated 4 miles/kWh, our full driving range to empty is about 60 miles on an 80% charge and 70 miles on a full charge. This can be compared with about 85 miles on a full charge when the car was new. But with the low charge warnings going off with ten miles of range still left in the battery, our comfortable usable range is now closer to 50 miles on an 80% charge and 60 miles on a full charge. (It should also be noted that we haven't yet lost any of our battery's indicated 12 capacity bars, as have some drivers in hot desert regions.)
Does all of this make the car less useful to us? Not in a big way, but I'd have to say yes. Here's an example. Last Sunday, we had no plans, so I charged to just 80% on Saturday night. In the afternoon, we decided to go out to a late lunch/early dinner at one of our favorite restaurants which is 25 miles away. With an 80% charge, our full range to empty was 60 miles, so we could have made the round trip of 50 miles. No side trips, mind you, but we could have made it. But the route home goes over the local coastal hills and we would have hit the "Very Low Battery" warning as we went up that hill, needing to coast down toward home "on (electric) fumes". I gave my wife the choice of which car to take and she chose our hybrid instead of the LEAF. It just wasn't worth it to her to take the LEAF and return home on the edge of running out of charge. Had I known that we might want to take such a trip, or if there was no concern about battery life by doing full charges, I would have charged the LEAF fully on Saturday night and we would definitely have taken the LEAF for our impromptu trip out to dinner.
Public Charging is Hit and Miss
Public charging is one of the ways in which EVs can gain more usefulness. There has certainly been a big surge in the last year in the number of Level 2 (240 Volt) public charging stations installed at shopping centers and workplaces. Public charging is handy when you find available charging stations, and this type of charging can certainly add usefulness to an EV and reduce the owner's dependence on home charging.
But can we depend on public charging to make trips that are beyond the EV's "tether" to its home garage? The key word in that question is "depend", and the answer is usually no. If the charging station is in working order, which they usually are, and hasn't been vandalized, the parking space might be "ICE'd" (blocked by a car with a gas engine), or occupied by a plug-in hybrid with a small battery, whose owner hasn't had the courtesy to move it when its small battery was full.
Various improvements in the public charging networks have improved things somewhat. Some charging stations now charge money per hour of use, discouraging those who want to park there all day and block use by those who need to charge. Mobile phone apps now show whether many public stations are in use or not, which gives drivers more confidence when choosing where to head in search of a station. Some networks offer the ability to reserve a charging spot for a given period of time.
But can we rely on a public charging station being available, enough to decide to drive the EV instead of the other car, when the EV's charge is too low to make the round trip? The only policy that will make the answer "yes" is the ability to reserve a charging spot. Otherwise, unless there are enough charging stations at a given locale that they are almost never full, we can't count on being able to get a charge without waiting when we arrive. And that wait may make the difference between a successful trip and a maddeningly delayed one.
For example, consider arriving at a movie theater in time for the movie, but without enough charge on board to make the return trip home because you didn't plan ahead or because you already drove the car down to a low level of charge. If a charging station is available, you just plug in and go to the movie. But if the charging station is in use or blocked or out of service, you can't afford to wait or to drive around looking for a charging solution. You need to get to the movie. Therefore, if you can't count on being able to charge, you'll choose to take your other car instead of your EV. This is a wasted opportunity to drive emissions free miles, just due to the uncertainty of having the charging station available.
What about public DC quick charging? Well, the roll-out of these high voltage, high amperage chargers has been slower than hoped and expected, to say the least. Two years ago, the Federally funded EV Project had some highly optimistic claims about the number of DC quick chargers they would install in Southern California. To date, the actual number installed has been very low. I know of only one of these stations installed by the EV Project in Southern California, and this one station is way out in Eastern San Diego County, away from most drivers' routes. There are a few other DC quick chargers in Southern California, installed by individuals or small start-up companies, and a few more in the San Francisco Bay Area.
The good news is that positive change is coming. Nissan announced recently that many of their dealers will be installing DC quick chargers. This makes a lot of sense, since many dealerships are located along major travel routes. With 30 to 40 minute quick chargers located conveniently, LEAF drivers will have a realistic way to charge en route or when an unexpected errand crops up. This will be a great selling point for prospective LEAF buyers who are anxious about range. Also, California will also be adding a new network of charging stations, planned to begin in 2013, most of them in the most heavily populated areas, many of them quick chargers, as part of a settlement agreement between NRG Energy and state government.
The LEAF (like most EVs) isn't a Road Trip Car, But That Doesn't Make it Useless
Some people have said that unless an EV can do everything that an ICE car can, including taking road trips, the EV isn't worth owning. For one-car families who make many road trips and for whom it doesn't make sense to rent a car for long trips, that is probably true. But EVs can fit in well in two-car families, as ours does. When a family has two cars, as millions of American families do, the EV can be very useful for local trips. As with our LEAF, the EV can actually do the majority of the family's annual miles.
The point to EVs is that they are only one of the solutions to our transportation challenges. Hybrid models will continue to be popular and will greatly increase the national fleet's mpg as more hybrids are introduced from more manufacturers. This includes hybrid electric delivery and work trucks. Driving plug-in hybrids will introduce many new owners to electric fueling while sparing them from range anxiety and the daily planning needed to live with full battery electric cars. Hydrogen fuel cell cars will begin entering the market within a few years. And improvements in the efficiency of traditional ICE and diesel vehicles will further reduce the US fleet's fuel usage.
As a vital part of this overall solution, EVs will play their role as zero tailpipe emission family transportation for commuting and local driving, and as a way to efficiently drive on green and renewable energy sources such as wind, solar and hydro power. As battery technology improves, costs will drop and driving range will increase. By putting EVs into daily use, the industry and the nation are gaining valuable knowledge and critical mass that will make more efficient cars possible in the near future. Since the world supply of cheaply and safely available petroleum will eventually run lower, it makes sense that EVs and other alternative fuel cars are part of our fleet today.
So even though EVs are not very good for making road trips, they are great local cars, and as such they can replace millions of miles per year that are currently driven on gasoline. In this way, EVs can take an important position in the overall solution to the problems of reducing our dependence on foreign oil, lowering our driving costs and reducing emissions from transportation.
Conclusion: Is the EV Movement a Success So Far?
To sum up my impression of the EV movement to this date, I have to say that I think that it is a limited success. The two strongest selling EVs, the LEAF and the Chevy Volt, are selling reasonably well, and they are available in all of the United States. (Argue whether the Volt is an EV if you wish, but the Volt can cover almost as many electric miles as our LEAF, with its two year old battery pack). Public charging stations are growing in number across the nation. Millions of electric miles have been driven over the past two years, with zero tailpipe emissions from any of those miles. While some emissions have come from electric power plants to support some of those miles, reliable studies show that the emissions from those plants are lower in most locales than tailpipe emissions from gasoline cars driving the same mileage. The 2013 models of the LEAF and the Volt show significant technical improvements compared with the 2011 versions, demonstrating steady technological improvement. Six new EVs and five new plug-in hybrids have come into the market, with more models of both types announced for introduction over the next two years. Clearly, the EV movement is gaining steam, and as gas prices continue their predicted rise, more and more people are looking for alternatives. And as drivers see more EVs on the roads, plug-in cars provide a viable option.
Efficiency Improvements Due in the 2013 LEAF
Details have been announced about the soon-to-be-available 2013 LEAF. While some of the changes are cosmetic, such as new paint, enhanced entertainment options and interior colors and leather seating, some of the changes will improve energy use and driving efficiency. It is even possible that driving range will increase in some models under some circumstances. These improvements include reduced vehicle weight, reductions in the power and torque ratings of the motor, doubling in the power of the on-board charger and shortening of the length of the charger cooling plumbing, improved regenerative braking, and improvements in the efficiency of the heater.
In the Japanese home market tests, the driving range of the 2013 LEAF improved by 14%, but US writers expect lesser improvements for the LEAF in the US EPA range tests. This is partly due to changes in the EPA tests since the 2011 and 2012 LEAF ranges were determined.
Our Electricity Costs
It looks like our utility (SCE) may have figured out the communications issue between our smart meter and their main system. At least, I was able to access an electronic bill on the SCE website for our January usage.
We had a pretty sunny January. In fact, this month was our most productive January by a few percent for solar power production since we installed our system six years ago. After our December "bill" (we are on net annual metering, so we only pay our bill once at the end of month 12 of our year) was about $62, I was pleasantly surprised that our January bill was only $36.56. That leaves a remaining credit balance of $30.72 for February's usage, the remaining month of our net metering year. Given that February is a short month, temperatures are getting warmer and solar hours are longer, I'm now predicting that we'll end our net metering year with a final bill of about zero. Our bill last year was less than $7 for all of our household usage and car charging, So this will be the second year of essentially zero cost for all of our electric power.
The Numbers: January 2013
2011 Nissan LEAF SL Placed in Service: March 30, 2011
All Home Charging Done Using: 240 Volt Aerovironment/Nissan Level 2 EVSE
Home Solar PV System: 24 Sunpower 215W panels totaling 5.16 kW DC mounted on a 20 degree South facing roof.
Total Solar PV Power Generated for Net Metering Year Ended February 2012: 8,568 kWh
Month: January 2013
Total Miles at Month End: 20,052 miles
Miles Driven in Month: 730 miles
Electric Power Used for Charging in Month: 237.5 kWh (measured at wall power source, includes public charging)
Public Charging in Month, Power Use: 0 kWh
Charging at Home in Month, Power Use: 237.5 kWh
Energy Efficiency, Month of January: 3.07 miles/kWh (wall to wheels)
Energy Efficiency, Month of January: 3.94 miles/kWh (in car main dash display, battery to wheels)
Efficiency Wall to Wheels in Month at 240 Volts: (3.07/3.94) = 77.9%
Energy Efficiency, Lifetime: 30.5 kWh/100 mi (wall to wheels)
Number of Home Charging Days in Month: 22
Most Electric Energy Used for Charging in a Day in January: 18.9 kWh (5.0 charging hours)
Most Electric Energy Used for Charging AT HOME in a Day in January: 18.9 kWh (5.0 charging hours)
Least Electric Energy Used at Home for Charging in a Charging Day in January : 4.4 kWh (1.16 charging hours)
Average Electric Energy Used for Home Charging in a Charging Day in January: 10.8 kWh (2.8 charging hours)
Household Power Used for Month: 657 kWh (without car charging)
Total Power Used for Month: 894 kWh (includes car charging)
Solar PV Power Generated for Month: 553 kWh
Net Power Used or Sent to Grid for Month: 341 kWh net used
January Electric Bill, So Cal Edison, Schedule TOU-D-TEV: $ 36.56
Solar Net Metering Year Total Cumulative kWh Used at Month #11: 2,070 kWh (Estimated Total kWh net used for the net metering year. This is total household and EV charging usage minus solar PV generation. Figures are from my tracking, SCE's tracking is messed up at this time.)
Solar Net Metering Year Total Cumulative Cost at Month #11: -$30.72 (Total energy and delivery costs for all power usage for the net metering year adds up to a credit balance after month #9 of our net metering year. This credit balance will pay for debits for future months when sunshine is less and Peak daytime credits are less beneficial.)
Cost for Charging Car in January: $0.00
Cost per Mile: $0.00
Cost for Charging Car, Lifetime: $0.00
Cost per Mile, Lifetime: $0.00
(If We Didn't Have Solar Power, Est Cost for Charging Car in January: $35.27)
(If We Didn't Have Solar Power, Est Cost per Mile in January: $0.048)
Maintenance and Repair Costs to Date: $98
Average (Mean) Miles per Driving Day in January: 26.1 miles
Average (Median) Miles per Driving Day in January: 28 miles
Longest Day's Driving in January: 64 miles (included a mid-day home charging session)
Longest Day's Driving in January Without Mid-Trip Charging: 64 miles
Shortest Day's Driving in January 5 miles
Number of Times we Took the Prius Instead of the LEAF Due to Low Charge: 5
Unexpected Low Charge and Unable to Reach Destination: Never
The LEAF has been completely reliable and it works well for the majority of the trips that we do. The combination of our LEAF with our Toyota Prius works perfectly for us. We take the LEAF when it has enough charge to make our planned trip, and we take the Prius for other trips, including our long distance trips. But sometimes the Prius is driven for simple convenience, or because my wife chooses to take the Prius because she assumes that I'll want to keep the LEAF at home because it's "my car". It turns out that the LEAF is driven about 60% of our miles. Also, our LEAF lease has a mileage limit of 12,000 miles per year, and we are driving the car 91% of those miles. So we could drive the LEAF a bit more than we are currently, but not significantly more without paying lease mileage penalties. We may try to increase our LEAF trips over the remaining 17 months of our lease. After all, we're paying for them in our lease, and the miles are free of fuel cost.
So, great stuff and a lot of positive thoughts about the LEAF, but what is life with an electric car really like? I want to devote the rest of this post to some real world discussion about the changes that driving electric brings to our lives, and the choices that we need to make, as well as my impressions of the degree of success of the recent EV movement in the US so far.
The LEAF is a Real Car
First of all, I need to tell you that the LEAF is a real car. It is roomy, well appointed, reliable and well equipped, with very good electronic displays, navigation, trip computer and infotainment features. Driving it is every bit as normal as driving any small to medium size family sedan. It accelerates well, in fact better than most cars at traffic lights, because of the electric drive train's instant torque. In the morning, I just unplug the car and get in and drive. It isn't slow like a golf cart. The LEAF keeps up with traffic just fine, including climbing hills. In fact, it's more fun to drive than most cars in its size class. It has a top speed of over 90 mph. So let's forget the notion that modern EVs like the LEAF are far out experiments whose time hasn't yet come, or forced sacrifices in the quality of our daily driving. Don't forget that we've put over 20,000 miles on this car in 22 months. These miles have been driven on daily errands, doctor appointments, family visits, shopping trips and pleasure drives, a full 60% of our driving, or more. If this car was a marginal experiment, it wouldn't have been possible for us to use it for so much of our family's driving.
We Have to Plan our Driving More than with a Gas Car
My planning starts each night, with a decision whether to charge the car or not, and whether to charge it fully or to only 80%, which Nissan calls long battery life charging. When making these decisions, I think about the current state of charge of the LEAF's battery pack and how far I plan to drive the following day. I take into account the number of miles I can drive the LEAF on a fully charged pack. In doing so, I take into account how much range the car has lost due to battery aging, whether the weather is going to be cold enough, or the roads wet, whether there are hills along my planned route, and whether I'll be driving on freeways which will limit my range due to higher speeds.
This planning may sound like a pain, but it becomes routine and it is not a big deal. Since the battery is full each morning, even though the "gas tank" is smaller than the gas tank in an ICE car, I can always drive 60 or 70 miles a day. Considering that our average driving day is about 30 miles, the range is usually no problem.
We Tend to Drive Slower and Use the Heater Less to Maximize Range
Above about 45 mph, the LEAF's driving range drops with increasing speed. If my planned route includes a total of 50 miles or more of freeway driving, even on a fully charged battery, I tend to drive more slowly, between 60 and 65 mph, and in the right hand lanes, in order to make my full round trip. If it is cold out, to drive the same distance, I usually choose to dress warmly and skip using the heater, because the heater on the 2011 and 2012 LEAF uses a lot of battery power. And if it is raining, using the defroster in the 2011/12 LEAF also turns on the air conditioner or heater, which saps range. Improvements in the 2013 LEAF solve these problems. Seat heaters and a steering wheel heater in the 2012 and later models help with creature comfort and they use less power than the main cabin heater. If I'm sure that I'll have plenty of range for my day's driving, I'll drive as fast as I want and use the heater freely.
How does this affect our driving pleasure? Well, I have to be frank and say that I'd rather drive as fast as the other traffic and I'd like to be able to use my heater when I want to. Believe me, this car is certainly fast enough to keep up with and pass other traffic. And with my LEAF festooned with "Electric" badges and my personalized license plate, I hate having to drive it slowly in the right lane of the freeway, essentially affirming for passing drivers the misconception that EVs are slow.
The So-Called "Cost Penalty" of EVs is Often an Illusion
Journalists often try to do a simple cost comparison of an EV or hybrid against an "equivalent" car with a gasoline engine, trying to come up with a timeline to pay off the purchase cost premium of the hybrid. The problem with this exercise for EVs is that an electric version of a similar car often turns out to be a much more satisfying vehicle because of the EV's superior acceleration, better handling due to a lower center of gravity, electronic amenities and smooth, quiet driving experience. So the simple math doesn't apply. An EV should be compared with a more satisfying luxury or sport version of the car, if such a car exists. And when that calculation is done, the supposed cost penalty of the EV can disappear.
Whether a given car is worth the cost to a given purchaser is an individual decision. A BMW 3 Series costs more than a Toyota Camry. They are both four door sedans, and they get similar fuel economy, but most people find value in the engineering, prestige and superior driving experience of the BMW, so the extra cost is worth it to them. When journalists try to peg the additional cost of an EV only upon the savings in fuel and maintenance costs, they are missing the point that the ownership experience of the EV can be very much worth the extra expense to some customers. Beyond lower operational costs and the improved driving experience that I detailed above, other motivators might be a desire to have a fuel source that is domestic, more predictable and free from the control of the oil markets and foreign governments, or a desire to reduce carbon emissions, or an attraction to a more technically interesting vehicle.
Usable Range is Less than Full Battery Charge
"How far can you drive?" That is one of the top three questions that EV drivers always get. Well, like any car, it depends on how fast you drive and how aggressively, whether the roads are wet or whether there are steep hills or overall altitude gain along the route. But for EVs, hills and altitude gain have an even greater effect on fuel mileage, very cold temperatures reduce range, and there is more of an impact if the heater is used. While for ICE cars gas mileage is better at freeway speeds, exactly the opposite is true for EVs. Moderate speeds around 45 mph and dry, flat roads are perfect for EVs, and LEAF drivers in some parts of the country have routinely gotten more than 100 miles of range under these conditions, with new cars and their fresh battery packs.
But can you at least use the full available charge of the battery? Well, technically, yes. But realistically, most people will want to play it safe and look to end the journey with a few miles left, when the LEAF's low charge warnings start sounding off. Nissan has chosen to be conservative in having the battery charge bars disappear and the low charge warnings sound when there are still about ten miles of range left in the battery pack (assuming moderate speeds and temperatures). Also, Nissan recommends that to extend battery life, whenever possible, we should charge to only 80% rather than giving the battery a full charge. And finally, as batteries age, they lose capacity.
So at our usual driving efficiency of an indicated 4 miles/kWh, our full driving range to empty is about 60 miles on an 80% charge and 70 miles on a full charge. This can be compared with about 85 miles on a full charge when the car was new. But with the low charge warnings going off with ten miles of range still left in the battery, our comfortable usable range is now closer to 50 miles on an 80% charge and 60 miles on a full charge. (It should also be noted that we haven't yet lost any of our battery's indicated 12 capacity bars, as have some drivers in hot desert regions.)
Does all of this make the car less useful to us? Not in a big way, but I'd have to say yes. Here's an example. Last Sunday, we had no plans, so I charged to just 80% on Saturday night. In the afternoon, we decided to go out to a late lunch/early dinner at one of our favorite restaurants which is 25 miles away. With an 80% charge, our full range to empty was 60 miles, so we could have made the round trip of 50 miles. No side trips, mind you, but we could have made it. But the route home goes over the local coastal hills and we would have hit the "Very Low Battery" warning as we went up that hill, needing to coast down toward home "on (electric) fumes". I gave my wife the choice of which car to take and she chose our hybrid instead of the LEAF. It just wasn't worth it to her to take the LEAF and return home on the edge of running out of charge. Had I known that we might want to take such a trip, or if there was no concern about battery life by doing full charges, I would have charged the LEAF fully on Saturday night and we would definitely have taken the LEAF for our impromptu trip out to dinner.
Public Charging is Hit and Miss
Public charging is one of the ways in which EVs can gain more usefulness. There has certainly been a big surge in the last year in the number of Level 2 (240 Volt) public charging stations installed at shopping centers and workplaces. Public charging is handy when you find available charging stations, and this type of charging can certainly add usefulness to an EV and reduce the owner's dependence on home charging.
But can we depend on public charging to make trips that are beyond the EV's "tether" to its home garage? The key word in that question is "depend", and the answer is usually no. If the charging station is in working order, which they usually are, and hasn't been vandalized, the parking space might be "ICE'd" (blocked by a car with a gas engine), or occupied by a plug-in hybrid with a small battery, whose owner hasn't had the courtesy to move it when its small battery was full.
Various improvements in the public charging networks have improved things somewhat. Some charging stations now charge money per hour of use, discouraging those who want to park there all day and block use by those who need to charge. Mobile phone apps now show whether many public stations are in use or not, which gives drivers more confidence when choosing where to head in search of a station. Some networks offer the ability to reserve a charging spot for a given period of time.
But can we rely on a public charging station being available, enough to decide to drive the EV instead of the other car, when the EV's charge is too low to make the round trip? The only policy that will make the answer "yes" is the ability to reserve a charging spot. Otherwise, unless there are enough charging stations at a given locale that they are almost never full, we can't count on being able to get a charge without waiting when we arrive. And that wait may make the difference between a successful trip and a maddeningly delayed one.
For example, consider arriving at a movie theater in time for the movie, but without enough charge on board to make the return trip home because you didn't plan ahead or because you already drove the car down to a low level of charge. If a charging station is available, you just plug in and go to the movie. But if the charging station is in use or blocked or out of service, you can't afford to wait or to drive around looking for a charging solution. You need to get to the movie. Therefore, if you can't count on being able to charge, you'll choose to take your other car instead of your EV. This is a wasted opportunity to drive emissions free miles, just due to the uncertainty of having the charging station available.
What about public DC quick charging? Well, the roll-out of these high voltage, high amperage chargers has been slower than hoped and expected, to say the least. Two years ago, the Federally funded EV Project had some highly optimistic claims about the number of DC quick chargers they would install in Southern California. To date, the actual number installed has been very low. I know of only one of these stations installed by the EV Project in Southern California, and this one station is way out in Eastern San Diego County, away from most drivers' routes. There are a few other DC quick chargers in Southern California, installed by individuals or small start-up companies, and a few more in the San Francisco Bay Area.
The good news is that positive change is coming. Nissan announced recently that many of their dealers will be installing DC quick chargers. This makes a lot of sense, since many dealerships are located along major travel routes. With 30 to 40 minute quick chargers located conveniently, LEAF drivers will have a realistic way to charge en route or when an unexpected errand crops up. This will be a great selling point for prospective LEAF buyers who are anxious about range. Also, California will also be adding a new network of charging stations, planned to begin in 2013, most of them in the most heavily populated areas, many of them quick chargers, as part of a settlement agreement between NRG Energy and state government.
The LEAF (like most EVs) isn't a Road Trip Car, But That Doesn't Make it Useless
Some people have said that unless an EV can do everything that an ICE car can, including taking road trips, the EV isn't worth owning. For one-car families who make many road trips and for whom it doesn't make sense to rent a car for long trips, that is probably true. But EVs can fit in well in two-car families, as ours does. When a family has two cars, as millions of American families do, the EV can be very useful for local trips. As with our LEAF, the EV can actually do the majority of the family's annual miles.
The point to EVs is that they are only one of the solutions to our transportation challenges. Hybrid models will continue to be popular and will greatly increase the national fleet's mpg as more hybrids are introduced from more manufacturers. This includes hybrid electric delivery and work trucks. Driving plug-in hybrids will introduce many new owners to electric fueling while sparing them from range anxiety and the daily planning needed to live with full battery electric cars. Hydrogen fuel cell cars will begin entering the market within a few years. And improvements in the efficiency of traditional ICE and diesel vehicles will further reduce the US fleet's fuel usage.
As a vital part of this overall solution, EVs will play their role as zero tailpipe emission family transportation for commuting and local driving, and as a way to efficiently drive on green and renewable energy sources such as wind, solar and hydro power. As battery technology improves, costs will drop and driving range will increase. By putting EVs into daily use, the industry and the nation are gaining valuable knowledge and critical mass that will make more efficient cars possible in the near future. Since the world supply of cheaply and safely available petroleum will eventually run lower, it makes sense that EVs and other alternative fuel cars are part of our fleet today.
So even though EVs are not very good for making road trips, they are great local cars, and as such they can replace millions of miles per year that are currently driven on gasoline. In this way, EVs can take an important position in the overall solution to the problems of reducing our dependence on foreign oil, lowering our driving costs and reducing emissions from transportation.
Conclusion: Is the EV Movement a Success So Far?
To sum up my impression of the EV movement to this date, I have to say that I think that it is a limited success. The two strongest selling EVs, the LEAF and the Chevy Volt, are selling reasonably well, and they are available in all of the United States. (Argue whether the Volt is an EV if you wish, but the Volt can cover almost as many electric miles as our LEAF, with its two year old battery pack). Public charging stations are growing in number across the nation. Millions of electric miles have been driven over the past two years, with zero tailpipe emissions from any of those miles. While some emissions have come from electric power plants to support some of those miles, reliable studies show that the emissions from those plants are lower in most locales than tailpipe emissions from gasoline cars driving the same mileage. The 2013 models of the LEAF and the Volt show significant technical improvements compared with the 2011 versions, demonstrating steady technological improvement. Six new EVs and five new plug-in hybrids have come into the market, with more models of both types announced for introduction over the next two years. Clearly, the EV movement is gaining steam, and as gas prices continue their predicted rise, more and more people are looking for alternatives. And as drivers see more EVs on the roads, plug-in cars provide a viable option.
Efficiency Improvements Due in the 2013 LEAF
Details have been announced about the soon-to-be-available 2013 LEAF. While some of the changes are cosmetic, such as new paint, enhanced entertainment options and interior colors and leather seating, some of the changes will improve energy use and driving efficiency. It is even possible that driving range will increase in some models under some circumstances. These improvements include reduced vehicle weight, reductions in the power and torque ratings of the motor, doubling in the power of the on-board charger and shortening of the length of the charger cooling plumbing, improved regenerative braking, and improvements in the efficiency of the heater.
In the Japanese home market tests, the driving range of the 2013 LEAF improved by 14%, but US writers expect lesser improvements for the LEAF in the US EPA range tests. This is partly due to changes in the EPA tests since the 2011 and 2012 LEAF ranges were determined.
Our Electricity Costs
It looks like our utility (SCE) may have figured out the communications issue between our smart meter and their main system. At least, I was able to access an electronic bill on the SCE website for our January usage.
We had a pretty sunny January. In fact, this month was our most productive January by a few percent for solar power production since we installed our system six years ago. After our December "bill" (we are on net annual metering, so we only pay our bill once at the end of month 12 of our year) was about $62, I was pleasantly surprised that our January bill was only $36.56. That leaves a remaining credit balance of $30.72 for February's usage, the remaining month of our net metering year. Given that February is a short month, temperatures are getting warmer and solar hours are longer, I'm now predicting that we'll end our net metering year with a final bill of about zero. Our bill last year was less than $7 for all of our household usage and car charging, So this will be the second year of essentially zero cost for all of our electric power.
The Numbers: January 2013
2011 Nissan LEAF SL Placed in Service: March 30, 2011
All Home Charging Done Using: 240 Volt Aerovironment/Nissan Level 2 EVSE
Home Solar PV System: 24 Sunpower 215W panels totaling 5.16 kW DC mounted on a 20 degree South facing roof.
Total Solar PV Power Generated for Net Metering Year Ended February 2012: 8,568 kWh
Our LEAF's Longest Range Full Charge to Empty ("Turtle"): 86.5 miles (at 4.0 mi/kWh on dash), April 2011.
Our LEAF's Most Recent Range, Full Charge to Turtle: 75 miles (at 4.1 mi/kWh on dash), July 2012
NOTE: Longer maximum range is possible if the LEAF is driven more conservatively. LEAF owners have achieved range of well over 100 miles.
NOTE: Longer maximum range is possible if the LEAF is driven more conservatively. LEAF owners have achieved range of well over 100 miles.
Total Miles at Month End: 20,052 miles
Miles Driven in Month: 730 miles
Electric Power Used for Charging in Month: 237.5 kWh (measured at wall power source, includes public charging)
Public Charging in Month, Power Use: 0 kWh
Charging at Home in Month, Power Use: 237.5 kWh
Energy Efficiency, Month of January: 3.07 miles/kWh (wall to wheels)
Energy Efficiency, Month of January: 3.94 miles/kWh (in car main dash display, battery to wheels)
Efficiency Wall to Wheels in Month at 240 Volts: (3.07/3.94) = 77.9%
Total Charging Energy Used, Lifetime: 6,117 kWh (Includes public charging)
Energy Efficiency, Lifetime: 3.28 miles/kWh (wall to wheels)Energy Efficiency, Lifetime: 30.5 kWh/100 mi (wall to wheels)
Number of Home Charging Days in Month: 22
Most Electric Energy Used for Charging in a Day in January: 18.9 kWh (5.0 charging hours)
Most Electric Energy Used for Charging AT HOME in a Day in January: 18.9 kWh (5.0 charging hours)
Least Electric Energy Used at Home for Charging in a Charging Day in January : 4.4 kWh (1.16 charging hours)
Average Electric Energy Used for Home Charging in a Charging Day in January: 10.8 kWh (2.8 charging hours)
Household Power Used for Month: 657 kWh (without car charging)
Total Power Used for Month: 894 kWh (includes car charging)
Solar PV Power Generated for Month: 553 kWh
Net Power Used or Sent to Grid for Month: 341 kWh net used
January Electric Bill, So Cal Edison, Schedule TOU-D-TEV: $ 36.56
Solar Net Metering Year Total Cumulative kWh Used at Month #11: 2,070 kWh (Estimated Total kWh net used for the net metering year. This is total household and EV charging usage minus solar PV generation. Figures are from my tracking, SCE's tracking is messed up at this time.)
Solar Net Metering Year Total Cumulative Cost at Month #11: -$30.72 (Total energy and delivery costs for all power usage for the net metering year adds up to a credit balance after month #9 of our net metering year. This credit balance will pay for debits for future months when sunshine is less and Peak daytime credits are less beneficial.)
Cost for Charging Car in January: $0.00
Cost per Mile: $0.00
Cost for Charging Car, Lifetime: $0.00
Cost per Mile, Lifetime: $0.00
(If We Didn't Have Solar Power, Est Cost for Charging Car in January: $35.27)
(If We Didn't Have Solar Power, Est Cost per Mile in January: $0.048)
Maintenance and Repair Costs to Date: $98
Average (Mean) Miles per Driving Day in January: 26.1 miles
Average (Median) Miles per Driving Day in January: 28 miles
Longest Day's Driving in January: 64 miles (included a mid-day home charging session)
Longest Day's Driving in January Without Mid-Trip Charging: 64 miles
Shortest Day's Driving in January 5 miles
Number of Times we Took the Prius Instead of the LEAF Due to Low Charge: 5
Unexpected Low Charge and Unable to Reach Destination: Never
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