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Tuesday, May 21, 2013

Take that, Exxon!: EV insights, Day 21

We've had our Mitsubishi MiEV electric auto for three weeks as of today.  Current mileage totals for our "fleet":

EV: 629
Prius: 240

Total: 869
Gallons of gasoline consumed: 4.8
Gallons of gasoline displaced through trade-in of Honda Insight hybrid for EV = 14.5
Fleet mileage: 869/4.8 = 181 miles per gallon
Fuel savings @ 4.5 cents per EV mile = 629*4.5 = $28.31

These numbers suggest annual gasoline displacement of roughly 250 gallons and fuel savings (counting the electricity consumed) of about $500.  As previously mentioned, that's based on trading in a 40-mpg auto, so for a 20-mpg auto, those numbers could be doubled.

- The EV is performing very nicely--it's now clear that we can consistently drive it twice to "town" (the "micropolitan" area consisting of Hanover, Lebanon, White River Junction, and Norwich) each day, with overnight fillups, even at the "slow" charging rate (using a regular 110 outlet), for at least several days without running low on battery charge.  We've used it exclusively, except when we have multiple commitments that conflict or overlap.

- As with the Honda we traded in, the range indicator is flighty--after the car is fully charged (the "charging" indicator light goes out), the range has so far read anywhere from 72 to 81 miles. It seems to go down faster when it's 81 than when it's 72, but that could just be my imagination--variables such as temperature, precipitation, cargo weight, headlight use, etc., all make it difficult to get precise, comparable measurements.  In any event, the lowest the range has gotten is about 40, except for the deliberate deep discharge described in my previous post.  While the EV takes 22 hours to charge from 0 to full, 10 hours of charging will take it from 40 miles on the range indicator to more than 70, so the charging fits well into a regular daily schedule.

I'll write a bit more about the MiEV's transmission settings in a future post.

Sunday, May 12, 2013

Take that, Exxon!: EV insights, Day 12

So, I've been out of town for most of the past week, but want to set down a few more thoughts while they are fresh. At this point, the mileage numbers since our EV arrived April 30 look like this:

EV: 367
Prius: 147

Not quite the 80 percent I was hoping for (71.4 percent), and I'm sure that was a little unrealistic. Still, the improvement over our previous transportation mix (two hybrids, one getting 50 mpg and the other 40 mpg) is obvious:

Previous: 514 miles, average 45 mpg = 11.4 gallons of gasoline
Current: 514 miles, 147 fueled by gasoline, average 50 mpg = 2.9 gallons

Another way to put it: we've gone from averaging 45 mpg to averaging almost 175 mpg (514 divided by 2.9), which I think is pretty cool. That in turn leads to the conclusion that the  mpge (miles per gallon of gasoline equivalent) rating doesn't tell the whole story. The mpge rating emphasizes that the EV is still consuming energy (certainly important to keep in mind), but doesn't communicate the full benefits in terms of gasoline use.  While the MiEV's mpge rating is 112, its actual mpg is, of course, infinity, and our average mpg is limited only by how many miles we can load onto it.

Yesterday, we fulfilled one of the basic MiEV battery requirements--a fairly deep discharge. The manufacturer advises driving it until the fuel gauge drops below two bars and then recharging it fully. After two trips Friday and charging overnight, its range indicator read 55 miles.  Two more trips yesterday took it down to 19, and then I drove it enough to take it to two bars (12 or 13 miles on the indicator) and then home.  It was exciting!  We live on the side of a hill, and the range indicator drops steadily when driving uphill.  The refuel warning was flashing steadily and I had visions of falling a few hundred yards short, which would have been a minor disaster. In the end, I eased it into the garage with 5 miles still on the indicator.  Whew.  Won't be doing THAT again anytime soon (the manufacturer says it needs doing every two years).

Some additional stats:

367 miles on the EV, fuel savings 4.5 cents/mile = total savings to date $16.51 (not too impressive, but we traded in a 40-mpg hybrid--if you replace a 20-mpg auto, the savings would be 9 cents/mile). For the fuel savings calculation, see this previous post.

Thursday, May 2, 2013

Take that, Exxon!

I posted here not long ago about taking a ride in a friend's electric vehicle, and how attractive it was. Well, after some dithering, we took the plunge and ordered one for ourselves. It arrived late Tuesday and we have just finished Day 2 of owning/driving.  It's great!

The perfect car for someone like me who likes to dig into the numbers.  So, here are a few early insights:

- This is a Mitsubishi i MiEV (we call it the mee-EHV) and it is rated by EPA to have a 62-mile range and fuel economy of 112 mpge (miles per gallon of gasoline equivalent).  What does that mean?  Well, EPA figures 33.7 kilowatt-hours (kWh) of electricity for the gallon of gasoline equivalent, so for that many kWh, the MiEV is supposed to travel 112 miles (as the saying goes, your mileage may vary).

- This means that the MiEV's battery "tank" only holds a bit over half a gallon of gasoline equivalent (62 divided by 112).  And it also means that the MiEV gets about 3.3 miles per kWh.  A kWh, in our neck of the woods, costs about 15 cents, so the cost per mile for fuel is 15/3.3 = 4.5 cents.  This compares with the cost of gas for the Honda Insight we traded in--$3.60 per gallon for 40 mpg, or 9 cents/mile.  And that's for a 40-mpg hybrid.

- The MiEV will also cost less to maintain, as it has a much less complicated motor (no oil changes). And I'm guessing that, as we focus on making it our main car for local driving, the wear and tear on our other auto, a Toyota Prius with just under 137,000 miles, will be drastically reduced.

As of Day 2, we've had five trips to town for meetings, work, etc.  We were able to take four of them with the EV, which has so far traveled 66 miles, leaving one for the Prius (18 miles).  I'm hopeful that over the long term, that ratio (close to 80% of local travel with the EV), can be maintained.

- 66 miles on the EV amounts to about 20 kWh, which is substantial--it's pretty clear that our total electricity bill is going to go up, perhaps nearly double, but that's because our previous usage was quite low.  At the same time, obviously, our gasoline spending is going to plummet.  Take that, Exxon!

OK, so enough geeky stuff.  

How does it look?  See above--you can be the judge.  I drove a VW Beetle for about 25 years, so a car's looks are not high on my list of required attributes.  

How does it handle?  Fine, drives like a normal car.  

What happens when you're merging onto a freeway and you need extra speed?  I think this is an interesting question, because I've been asked it a couple of times, in almost exactly the same words--evidently it is something that really preys on some drivers' minds.  Hasn't happened yet, but the pickup is quite good and ... I drove a Beetle for 25 years.

This post is already fairly long, so I'll leave it at that for now--I can provide more specifics about the transmission settings and gauges later.  We have a bare-bones version of the MiEV--to find out more about the deluxe version, see the excellent series of blog posts that begins here.

Other questions?  Ask away.

Sunday, April 21, 2013

When 'head-on' isn't really

"City tackles climate change head-on" reads a recent article in the La Crosse, Wis., Tribune.  Sounds exciting, doesn't it?  But the story that follows is a letdown--enough so to inspire this brief blog post.

What La Crosse is doing:

- Hosting a climate change workshop "to build consensus about pragmatic adaptations authorities can make to changing weather."  I assume this involved some serious dissemination of information about climate change's impact, so that's a good thing.

- Adding more green spaces on the city's south side to handle the runoff from heavy rain events.

- And ... that's it.  Oh, perhaps not--the story makes a point of noting that La Crosse "made clear in its application that climate change a distinct challenge to [its] future."

And that seems to be the point of the headline: the city actually came right out and said, in effect, that it thinks climate change is real.

That too is a good thing, but in fact, "tackling climate change head-on" means, in the simplest of terms, reducing fossil fuel use.  Everything else is just papering over the problem.  In this instance (the extra green space), it's a little like giving someone with a broken arm aspirin, because his arm hurts.

Energy efficiency and non-fossil energy, as much as possible, as soon as possible, is what we need to do, or as Joe Romm puts it, "deployment, deployment, deployment" of technologies that reduce fossil fuel use.  As Mr. Romm puts it here

"The crucial climate strategy is aggressive deployment of every last bit of available low-carbon technology starting ASAP.  Anyone who isn’t in favor of that strategy understands neither climate science nor the current state of clean energy.  Sadly, that covers most of the traditional media and so-called intelligentsia."

Sunday, April 7, 2013

Inferno (the imaginary one)

No, this is not a post about the southern U.S. in ... 2030?  2040?  It's about an enjoyable science fiction (actually, perhaps more fantasy) novel, Inferno, by Larry Niven and Jerry Pournelle, published a number of years ago.

Inferno is about a science fiction writer, Allen Carpenter (who goes by the name Carpentier to lend an air of sophistication).  Carpentier dies falling out of a hotel room window while trying to impress fans at a convention and finds himself in what turns out to be a large bronze bottle.  He's there for a long time, and ultimately screams, "For the love of God, someone help me!"  Presto, he's out of the bottle and in the vestibule of Hell--or rather, Hell as described in Dante's Inferno.  After a lengthy and entertaining journey through its various levels, he helps a fellow resident make his way out, and vows to stay and help others do the same.

So that's a very brief synopsis. Two points about this book come to mind when I think about global warming.

First, at one point, Carpentier encounters a priest who has been in Hell since the Middle Ages, when he was condemned for selling false "indulgences" (essentially, tickets by which the rich could supposedly buy their way into Heaven).  Carpentier stops to talk to the priest, whose punishment is to wear a (massively heavy) solid gold robe.  The priest says little and starts to walk away, whereupon Carpentier asks why he can't stop and sit down.  The priest answers:

"I could fall on you. But it may be that you do not know what you say.  If I stop, this robe grows hot.  It is too hot now.  It grows hot slowly, and it grows cool slowly.  Now, goodbye." [emphasis added]

That's the thing about global warming--the Earth grows hot slowly (the good news). The bad news is that it grows cool slowly as well--it's irreversible, on a time scale of centuries.  Also, the good news is not really that good, in that it has lulled us into a false sense of security--it's been 25 years since the heat wave of 1988, and we are just now beginning to see the weather extremes pile up.

Second, once Carpentier has figured out that Hell is real, and not just a stupendous feat of futuristic engineering, he focuses on a larger question--why does God allow it to exist at all?  People are undergoing infinite torture as punishment for the finite sins, however loathsome, they committed during their lives.  In the end, he finally decides on the answer:

"There's only one possible excuse for Hell, and I almost missed it in the ravings of a crazy psychiatrist.  It has to be the final training ground.  If nothing can get a soul into Heaven in its life, there's still Hell, God's last attempt to get [its] attention.  Like a catatonic in a hotbox, like me in that bottle, if Hell won't make a man yell for help, then it was still worth a try."

Hell, in Inferno, is like the climate.  We can ignore it, deny that it's changing, lose ourselves in sports and celebrities and politics and ethnic/religious hatred and all sorts of other distractions--but the climate doesn't care.  It's just going to keep getting worse and worse, year after year, until we can't look away any longer.  For all our sakes, I hope that day is soon.

Saturday, April 6, 2013

Solar system turns 2000! (kWh)

I've been meaning to provide updates on the output of our backyard solar system, but have fallen behind due to the press of other activities (relating to wind power and climate change).

In any event, while the winter months were, predictably, very slow, electricity production has picked up in the past six weeks, and our system currently stands at 2.42 MWh (megawatt-hours), or 2,420 kilowatt-hours).

So, let's run the numbers again.

In terms of energy, it's the equivalent of 72 gallons of gasoline, or enough to drive one of our hybrid autos about 3,200 miles.

In terms of generating electricity, the numbers are bigger, because the combustion process for fossil fuels wastes energy.  2,420 kWh is equivalent to burning about 2,400 pounds (more than a ton) of coal, or 142 gallons of diesel oil (New England, where we are located, still burns plenty of diesel oil to generate electricity).

In terms of carbon dioxide (CO2) emissions, the New England utility system gives off about 0.9 pounds of CO2 per kilowatt-hour of electricity, so our 2,420 kWh means about 2,200 pounds of carbon dioxide has been kept out of the atmosphere.

From February 15 to March 15, our system generated 208 kWh, just over two-thirds as much electricity as we used (308 kWh).  Looking forward to seeing our utility bills dip below zero this month.

Sunday, March 24, 2013

EV or not EV? That is (not really) the question

My wife and I got a ride last evening in a Mitsubishi MiEV and were very impressed. It's a small but reasonably roomy 100 percent electric 4-person vehicle, range 50-60 miles, 22 hours to charge (from zero to full) on 110, 7 hours to charge on 220.  Talking with its owner brought out an aspect to those numbers I hadn't considered, which is that if you drive it 20 miles, it can probably be fully charged again overnight because it won't be down to zero.  Duh. Which means, in turn, that if your commute is not too long, you may be able to use it every day for several days ...

Anyway, that prompted a discussion, because my wife had seen a reference somewhere recently to how EVs (electric vehicles) may not be as clean as hybrids, depending on the fuels that the utility system in your region uses to generate electricity. I've also seen this issue raised a number of times, perhaps most prominently in a New York Times article discussing a Union of Concerned Scientists (UCS) study on the issue.

I have a beef, not with UCS--which is a great organization--but with the implications that can easily be drawn from such a study, specifically the implication that anyone, anywhere, should feel free to go ahead and buy a gasoline auto if the utility system in the region depends heavily on coal.  Don't do it!

I say not so, and here's why.  The problem with carbon emissions from an EV, such as they are, is not inherent with the EV, it's a problem with the utility system, and a problem that can actually be fixed, by the utility building or purchasing more renewable energy (solar, wind, hydro, biomass) power plants.  The problem with carbon emissions from a gas auto is inherent with the auto, and you're investing in a (small) piece of infrastructure that will never get better until it goes to the junkyard at the end of its useful life, 10 to 20 years from now.

The Times article, and the UCS study itself, suggest how easy it is to misread the issue.   The article ends as follows: "'To prevent the worse consequences of global warming,' the report concludes, 'the automotive industry must deliver viable alternatives to the oil-fueled internal combustion engine, i.e., vehicles boasting zero or near-zero emissions.'" (emphasis added)  But what about the utility industry?  It's remarkable that it isn't mentioned, given the subject of the study. More importantly, it's remarkable because using electricity to break into the transportation energy market is a huge potential opportunity for electric utilities to expand their business.  Geez.

(I've had at least one argument on the Web about a closely related topic.  The people involved were very environmentally conscious, and dissing the idea of driving entirely for the same reason, saying that bicycling is the only way to go.  In essence, I told them, "If you want to see gasoline autos for the indefinite future, just keep belittling EVs and that is what you will get.")

Luckily, it turns out that our region (northeastern U.S.) has a relatively low-carbon generating mix, and so an EV tops the best hybrid, which means there is a good chance we will pop for one.  To me, it's a no-brainer, not only because of the reasoning above, but because buying or leasing it helps demonstrate there is a market and sends a message to other drivers who see it around town.

The one (very minor) downside?  Owning an EV will boost our electric bills a tad, just as we are beating them into submission with a backyard solar system.  Still, that's a minor issue, as driving an EV costs roughly 1/4 as much per mile as driving a gasoline auto.

Misinformation in Vermont's wind power debate

Vermont's State Senate is currently debating a bill, S. 30, that would impose a set of new restrictions on the siting of renewable energy facilities in the state.  I'm opposing this bill, which would throw another roadblock in the path of efforts to reduce greenhouse gas emissions.  If you would like more information on this debate, a good basic resources is the Vermont Public Interest Research Group's Support Wind page.

This specific post responds to a post on the Norwich, Vermont, town listserve by Ms. Clare Holland, of Sharon, Vt., who is a supporter of S. 30.  I've responded briefly on the listserve, but said I'd add some comments here for those who want more detail.

A few errors and omissions from Ms. Holland's posting:

- Ms. Holland makes much of the fact that only 4% of Vermont's carbon dioxide emissions are from electricity generation. In fact, consumption of electrical power in Vermont accounts for much more than that, because all marginal consumption is provided by fossil plants elsewhere in the region. Vermont uses/consumes 5.6 billion kilowatt-hours of electricity a year, which at the marginal New England emissions rate of 0.943 pounds per kilowatt-hour equals 2.64 million tons of CO2 attributable to electricity consumption in Vermont. Adding that to the 6.3 million tons of CO2 actually emitted in Vermont means electricity consumption accounts for 30% of Vermont’s CO2 emissions, not 4%.  The cost of operating a wind farm is very low, so whenever the wind is blowing, the electricity it generates displaces electricity from the most expensive (usually oldest and most polluting) power plant on the New England ISO utility system.

- New renewable energy power plants in Vermont are already subject to the same aesthetic and other standards as are contained in Act 250.  The key difference is that under Section 248, the Act-250-like permitting regulation that governs power plants and infrastructure, there is no local veto.  Why?  Because a balance must be struck between finding a way to produce the energy we all need and the rights of people to object to projects "in their back yard."  Section 248 represents that balance, negotiated over a number of years through the legislative process.  Now the State Senate, after a few weeks of discussion which have been notable for the circulation of wild misinformation about wind, proposes to toss that process out the window.

- With respect to bird fatalities at wind farms, the answer is simple: wind farms are not a threat to birds in general.  A recent study estimates that U.S. cats kill 2.4 billion birds a year, while a summary of studies from more than 100 wind farms results in a finding that less than 200,000 die as a result of colliding with wind turbines.  In short, cats kill more birds in one hour than all U.S. wind farms do in a year.