Diatribes of Jay: Sun-Powered Driving

[For a 2018 Thanksgiving Message, click here. For a list of links to recent posts in reverse chronological order, click here.]
[For a five-day post update on the following post, click here.]
Faithful readers of this blog know I’ve been considering what electric car to buy for over eleven years. For over five years, I’ve had a 6-kilowatt ground-mounted solar array, which produces far more energy than I need to run my home. Since I installed it, I’ve not paid a penny for electricity. Instead, I get a check from my power company every month.

But I’ve long waffled on the electric car to go with the solar array. My fiancée called it “the great dither,” but it’s now over. The “solution” turned out to be the same as I first entertained eleven years ago: the Chevy Volt.

That car also turned out to be far cheaper than I’d figured. With the Volt, I’m driving nearly entirely on the Sun’s energy, at least while at home in Santa Fe. And I’m doing so on a budget. Here’s how.

The first trick was leasing, not buying. GM has incredibly good leasing deals. Your total outlay depends on your credit rating, but if you have a good one the deals are hard to resist.

I walked out of the showroom with a brand new 2018 Chevy Volt for a total down payment of $1,980.33. That’s less than an old, beat-up used car would cost! Monthly payments on a three-year, 10,000 mile-per-year lease have been less than $386. (They vary a bit each month, so I can’t put my payments on billpay autopilot.)

My total outlay over the three-year lease will be about $15,876. When the lease expires, I can buy the car outright for about $20K more. Or I can turn it in and buy a Tesla Model 3—which by then may have worked out its production and start-up kinks. The Volt has already worked out it’s own start-up kinks: it’s now in its third generation. Instead of its original 35 mile electric-only range, it now has a 56-mile electric-only range when fully charged.

And what a sweet piece of engineering it is! There’s a big, steep hill south of Santa Fe called “La Bajada”—“The Incline” in Spanish. With my fiancée and a bunch of luggage in the car, I put it in cruise control at 82 MPH (the most I thought I could get away with in a 75 MPH zone) and zipped up the hill with ease. Since everything in the car runs electrically or electronically, the cruise control didn’t dither, as I had in deciding what electric car to get. It worked like, well, an electronic machine. And ordinary driving is quick and responsive, if not quite as much so as in a Tesla Roadster.

One of the most exciting things about the Volt is its noise, or lack thereof. It makes almost no sound in electric mode, and of course it produces no exhaust. You can run the electric motors in your garage, as long as you like, with the garage-door closed, and not worry about carbon monoxide.

The Volt’s electric operation is so quiet that an external sound generator kicks in whenever it’s going less than 18 MPH, so as not to blindside pedestrians or your kids playing in the driveway. The neatest sounds are a little artificial “whoosh” that the dashboard makes when you turn the car on, and a similar “shutting down” sound when you turn it off.

Although the Volt is a small car, I found listening to music while traveling on the highway to be an entirely new experience. I could hear all the musical highs and lows that booming of the engine and exhaust prevented me from hearing in other cars. The only sounds you hear with the Volt in electric mode are wind and tire noise.

The Chevy Volt is a “serial hybrid.” That means it has a small internal combustion engine (“ICE”), which doesn’t connect directly to the wheels. Instead, the engine drives a big electric generator in “series” with the electric motors, which charges the battery. The electricity from the ICE’s generator can also directly power the two electric-drive motors that move the car, one for each front wheel.

This is how diesel locomotives work in the railroad industry. The diesel engine just drives a big generator, which powers electric motors on the wheels. Thus the Volt has no transmission. Have you ever heard a subway car change gears?

When it runs, the ICE runs at a constant speed, optimized for generating the right amount of electricity. This operation produces far less wear and tear on the engine than in a conventional car, with all the strain of starting, slowing, shifting and stopping the ICE’s crankshaft directly. While driving up La Bajada, I could barely hear the ICE running hard to supplement the big battery’s charge, which then was almost depleted.

I could go on about the car’s electronics. It has two USB ports to keep the driver’s and front passenger’s cell phones charged. It has the usual “hand’s free” Bluetooth-to-cellphone feature. The audio system can play songs stored on your cellphone, iPod or iPad automatically. The front console can keep some cell phones charged inductively, i.e., without hooking them up. And computer screens can let you see all four tires’ pressure levels plus the main coolant’s temperature from the driver’s seat, as well as local speed limits.

But since my other car is nine years old, I’m probably too impressed by what now may be standard electronic displays. So let’s talk about Sun-powered driving.

Even with my home solar array, Sun-powered driving takes a little extra effort because the solar array only generates electricity during the day. It can charge the Volt best between the hours of 7:30 am and 5:30 pm daylight time.

So I have to force the car to charge itself only during those hours. Otherwise, the car would charge itself mostly on coal, which produces the vast majority of conventional electricity in northern New Mexico. (I hope our new Democratic governor will have something to say about this dismal picture, in one of the sunniest and windiest of American states.)

Fortunately, the Volt has a feature, designed for another purpose, that can be adapted to Sun-powered driving. An on-board computer allows you to set the charger to run only during your power company’s “off-peak” hours. Normally, those are hours when electricity usage is generally low and therefore so are electricity prices per kilowatt-hour.

Those times occur mostly at night, but the computer has a twenty-four hour clock. So you can set them during the day if you choose.

That’s exactly what I do. I set the car to charge during “off peak” hours only, and I set the “off peak” hours as my solar array’s 7:30 am to 5:30 pm peak period (daylight time). I thus force the car to charge itself only on the Sun, and it does so automatically. I just plug the car into my garage wall when I get home and double-check the computer settings. The on-board computer does the rest, and a little green LED on the dash signals, by blinking, how charging is going.

I can Sun-drive so easily because I’m retired and don’t go into town every day. If I were still working every day, I would have to buy a Tesla Powerwall battery to store my solar array’s energy output during the day and save it for car-charging at night.

If you have a Volt but not a solar array, you may not be able to Sun-drive. But here’s the thing. You can still avoid oil-driving and so flip the bird to the Saudis, Vladimir Putin, and all their oil reserves.

Oil generates virtually no electric power in any power company, only on cars, planes and ships. So every time you charge your car from your own electrical outlet you will be saving oil. You will also be redressing our geopolitical power balance with nations whose chief claim to greatness is the fortuity of having 100-million-year-old dead trees buried under their land.

If you want to go a bit further and reduce the acceleration of global warming, you’ll have to take an extra step. You’ll have to find out whether most of your local electricity comes from coal, as it does in my part of New Mexico. If so, you’ll have to install a solar array (or a windmill) to charge the car. Otherwise, you’ll be driving on coal, not the Sun’s energy. Coal produces about twice as much carbon dioxide per mile of driving as either gasoline or natural gas and so contributes doubly to accelerating global warming.

But you don’t have to drive on the Sun’s power. Even if you don’t have a solar array or windmill, and even if you charge your Volt, Tesla or other electric vehicle from your electric line, you’ll still be doing the environment, our planet’s climate, and geopolitics a favor, as long as your electricity doesn’t come from coal.

If your electricity comes from nuclear or hydroelectric power, you won’t be producing any greenhouse gases at all. If it comes from natural gas, you’ll be producing slightly less greenhouse gas than you would driving on gasoline, and a lot less smog. As long as your electricity doesn’t come from coal, you can help reduce greenhouse gases, help oil reserves last, and reset the imbalance of geopolitical power that random oil deposits create. You can find out from your electricity bill (which sometimes says where your electricity comes from) or from Web research, how much coal, if any, your local power company uses.

As for me, my Volt now lets me enjoy Sun-powered driving nearly all the time. I had to use some gasoline to “reposition” it from the Bay Area, where I leased it, to Santa Fe, where I live. But even on that long trip, the car’s computer reported well over 40 MPG efficiency, in part because I charged the car from B-n-B outlets during our trip.

Once we got to Santa Fe, I used only a couple of gallons of gas over two months. I could drive up another big hill at highway speeds to and past town, toodle around town, and drive back, all on electricity derived from the Sun. Only once, as I was driving up to my long home driveway, did the ICE at last kick in. The computer reported an average of 240 MPG.

That’s not perfect, but it’s good enough. It’s a lot better than driving on coal or rewarding the Saudis for brutally murdering a talented journalist living and working in our country and supposedly protected by us. And when you add the quiet, smooth, powerful, and even drive to all the electronic goodies, Sun-powered driving is positively Nirvanic.

Footnote. The Volt uses lots of different fluids, most of which are specialized. Its main coolant, which appears to serve both the main battery and the engine, is not water. Instead, it’s a synthetic liquid that doesn’t boil over until 265℉. I discovered this while reading the manual after stopping by the road while going through Arizona at 80 MPH on a very hot day, when the coolant’s temperature read well above the boiling point of water, 212℉.

Endnote on Charging Stations. Some people with electric cars obsess a lot over charging stations. You don’t have to do that if: (1) you only travel locally, well within your car’s all-electric range; (2) you drive farther only along major Interstate highways, which have charging stations strategically located for long-range (250-miles) all-electric cars like the Teslas and Chevy’s Bolt; or (3) you have a Volt. If you keep a third of a tank of gasoline in the Volt, as its manual recommends, that will give you well over a hundred extra miles of emergency gasoline driving range and so avoid both range anxiety and getting stranded.

In the end, that’s the main reason I eventually settled on the Volt after my long dither. Earlier, I had nixed the Volt because I wanted to be an electric-car “purist.” I didn’t want to carry a heavy ICE around with me if I didn’t intend to use it often.

But I changed my mind on discovering that most of my driving would be within the Third-Generation Volt’s longer all-electric range. Having the extra gasoline range for emergencies would avoid searching for charging stations whenever I wanted to travel farther, for example, from my home near Santa Fe down to Albuquerque and back, about 120 miles round trip. (With a full charge and a full gas tank, the Volt’s total range is 420 miles.)

On my first such trip I discovered another good reason having the extra range: standardization. Tesla charging stations use their own plugs, and other stations use a variety of payment mechanisms, rather than a simple credit card. I’m now in the process of researching which one(s) is/are the best in my area (the Southwest) for me to sign up with.

One of the greatest joys of owning an electric car is “gassing up” in your own garage, without ever having to go to a gas station (or hardly ever!). With the extra margin of range that a few gallons of gasoline provides, I can have that joy for a number of months without worry. On the other hand, if your main long drive is a long commute to work or to an alternative work location, or to a special store or a relative’s or friend’s home, it’s not hard to research the needed charging stations for a known route and order the necessary cards or payment mechanisms. That’s not my case.

Another small consideration in leasing the Volt was weight. The big Teslas with long range weigh about 5000 pounds empty. That seemed, and still seems, excessive for dragging around my 150-pound body.

The Volt has a much smaller main battery, about one-fifth as heavy, just a few hundred pounds. Its ICE weighs far less than the other four-fifths of a longer-range battery, which probably tops 3000 pounds. That’s so even if you throw in the few gallons of gasoline that the manual recommends for the Volt’s extra range in routine all-electric use.

If you’re the kind of person who wants to have a hugely heavy car to bash the other car (and save yourself) in an accident, by all means go for it! But the engineer in me can’t help seeing all that extra weight as waste, even if only the Sun’s power drags it around.

To each his own. That’s why we have such a big car market. But all things being equal, I’d prefer a lighter car, even if its cornering may sometimes seems less solid without all the Tesla’s low-center-of-gravity ballast. So that’s what I got.

Overall, and at the current stage of development of the electric-car market, I see the Volt as the best tradeoff among range, range flexibility, weight, price, performance and having worked out all the kinks. My two months of use so far have only confirmed that choice. Kudos to Bob Lutz, the retired GM manager and car guy most responsible for the Volt, and for announcing the corporate decision that began the electric-car stampede! Update on weight, efficiency and per-mile running cost, five days post-publication
Two practical points are worth making, one implicit, one unmentioned. First, if you don’t like wasting energy in any form (even if it comes from the Sun), the Volt is a better choice than a luxury Tesla or its equivalent. The reason is weight. The curb weight of a 2018 Volt is, on average, 3,531 pounds. The curb weight of a Tesla model S is, on average, 4,794 pounds. So what you pay for the Tesla’s extra 200 miles or so of range is an extra 1,243 pounds, or almost half the curb weight of a subcompact car.

You don’t pay in performance for that extra weight, because the roughly five times larger battery overcompensates, providing lots of oomph on acceleration. But you do pay for the extra weight in efficiency. You take roughly a third more electrical energy to drive a luxury Tesla a given distance than the Volt.

If your electricity comes from your own solar array or windmill, that’s only a theoretical injury. It hurts nothing but your pride and conscience. Yet if your electricity comes from a nuclear or hydroelectric power plant, or from commercial renewable sources like solar arrays or windmills, your excess weight and electricity usage deprive others of electricity and drive up rates. If your electricity comes from fossil fuels, you are also increasing the acceleration of global warming and probably bringing the runout time of natural gas closer. In any of these cases, driving the lighter electric car conserves power and generating capacity more and, if fossil fuels are used, produces fewer greenhouse gases.

The Tesla Model 3 has a similar but smaller infirmity. Its average curb weight is 3,955 pounds, only 424 pounds heavier than the Volt’s. A couple of big passengers could make that up.

So the Model 3 uses only about a tenth more energy to travel a given distance than the Volt. From the point of view of conservation and efficiency, it’s a much more reasonable choice than the high-ticket, high-performance luxury Teslas offering the same 250-mile electric range. The only trouble is having to wait two or three years for Tesla to work off its production backlog (unless you already have a reservation).

The second point is easy to make in a table: mileage cost. The Volt costs less per mile to run than a comparable ICE car, and the cost of electricity is much less likely to change drastically than the cost of oil and gasoline. The calculations require only simple arithmetic, as follows:

Energy Cost of Driving, in Cents per Mile
for 2018 Volt and Comparable ICE Car

Energy Source	Underlying Price Parameter	Underlying Mileage Parameter	Cents per Mile Driven
Electricity	12 ¢/kWh	2.93 mi/kWh	4.1 ¢/mi
Gasoline	$2.493/gal	40 mi/gal	6.23 ¢/mi
Gasoline	$3.556/gal (CA)	40 mi/gal	8.9 ¢/mi

Notes: The price parameter of 12 ¢ per kilowatt hour is the national average residential price for electricity, but local prices vary considerably. The electric-car mileage parameter is the 2018 Volt’s fully-charged range (54 mi) divided by its battery’s capacity, or 18.4 kWh. The gasoline price parameters are for unleaded regular gas for November 30, 2018. The lower parameter was the national average for that day; the higher was the average California price for that day [roll cursor over state]. The mileage parameter of 40 MPG is about the highest that even hybrid ICE cars can achieve reliably in regular service.

Of course, higher mileage figures would produce lower mileage costs. But even if mileage reached 50 MPG—a figure that the president just found too high to ask car makers to achieve by 2025—that would only reduce the respective per-mile cost figures to about 5 ¢/mi and 7.1 ¢/mi, respectively, still both higher than the Volt’s 4.1 ¢/mi.

The moral of the story is that you don’t have to be rich or lay out $70K for a car to drive on the Sun’s energy or avoid fossil fuels. You can do so on a budget and avoid running down the world’s rapidly dwindling supply of oil. If you live in a non-coal-generating area, you can drive without using any fossil fuels or at least drive on natural gas, which produces slightly fewer greenhouse gases and a lot less smog and promises to be around longer.

Links to Popular Recent Posts

Diatribes of Jay

26 November 2018

Sun-Powered Driving

[For a five-day post update on the following post, click here.]

Update on weight, efficiency and per-mile running cost, five days post-publication

Links to Popular Recent Posts

3 Comments:

About Me

Previous Posts