I took a closer look at the Town’s report on leaf mulching and re-did my table of the vehicle-miles required to gather and dispose of Vienna’s leaves. The conclusion remains the same — all the options require roughly the same number of vehicle-miles.
But it’s also now crystal clear that most of the mileage comes in trucking the leaves out to Loudoun Composting.
I decided to ask the obvious question: How much fuel could be saved by taking the leaves to the closer-in I-66 solid waste transfer station, and how much more would that cost (due to the higher disposal fee).
Ultimately, the question is, would that be a reasonable way to reduce the Town of Vienna’s C02 emissions? And the answer is a resounding no. That would cost over $2000 per ton of C02 emissions avoided, far above typical benchmark rates in the $50 to $150 per ton range.
It would be an expensive way to make a modest environmental statement. If there is a goal of reducing greenhouse gas emissions, there are options that would yield a much bigger bang for the buck.
Details follow.
I don’t know if this would even be feasible, but I just thought I’d try to work out the fuel consumption difference between the current proposal (truck the leaves to Loudoun Composting) against an alternative of trucking them to the Fairfax County I-66 solid waste transfer station.
The facts are these, from the Town’s report (and a little more research).
- Loudoun now charges $30 per ton disposal of leaves.
- Fairfax currently charges $44 per.
- The round trip to Loudoun is 33 miles.
- The round trip to the I-66 transfer station is 18 miles.
Finally, the Town collects about 7500 cubic yards of leaves, which at 350 lbs per cubic yard, works out to (roughly) 1300 tons of leaves, and 375 trips to dispose of that via trucks with 7,000 lb capacity. (The Town’s report used a slightly higher figure, averaging the last three years of leaf pickups.)
The only big unknown is the fuel economy of those trucks. The Town gives that in terms of cost per hour. I’d like to know it in terms highway miles per gallon of diesel. And, unlike cars, it’s ridiculously hard to find reliable fuel economy numbers for heavy-duty trucks. (The Town uses tandem-axle dump trucks.)
My only option is to take an educated guess. Based on a few models of tandem-axle dump trucks, I’m guessing the Town’s trucks might be able to get 9 MPG on the highway.
So now, it’s just a matter of math. The I-66 landfill is closer, but charged a lot more for leaf disposal. Going there reduces fuel consumption/CO2 emissions, but dramatically raises disposal fees. How does that all shake out in terms of the cost of reducing our CO2 emissions?
With that, I calculate that using I-66 instead of Loudoun Composting would cost more than $2000 per ton of C02 emissions avoided. Typical benchmark or threshold levels are more like $50 to $150 per ton. Changing the delivery site would be a ridiculously inefficient way to try to reduce the Town’s total greenhouse gas emissions.
A real-life example to put that into perspective.
My wife bought a new car a few months back. After researching the market, we decided that buying a plug-in Prius (the Prius Prime) was an absolute no-brainer. The battery has a range of a bit over 30 miles, but that’s been enough to electrify nearly all of our car transport. There’s no “range anxiety”, because once the battery is discharged, it’s just a standard Prius. And it plugs into a regular wall outlet, so we didn’t need to rewire the garage to use it.
Best of all? Factoring in the Federal tax credit, it’s was cheaper to buy a Prius Prime than to buy a standard (non-plug-in) Prius. Courtesy of our generous Uncle Sam, the plug-in capability was “free”. (Meaning, somebody else paid for it.)
Let me now roughly work out my cost per ton of C02 emissions avoided by the decision to buy a Prius Prime over a regular Prius, ignoring the Federal tax credit.
Ignoring tax credits, the plug-in version of the Prius (the Prius Prime) costs about $3600 more than a standard Prius. (With the Federal tax credits, it’s actually slightly cheaper to buy a plug-in Prius).
Over a 150,000 mile vehicle lifetime, a standard Prius will produce about 31 tons of C02 emissions, based on the EPA estimate of 52 MPG, and roughly 21 pounds of C02 per gallon of gas burned. My calculation is that in Virginia, electrically-powered miles in the Prius Prime result in a 60 percent reduction in C02 emissions, relative to gasoline-powered miles. (That will, of course, vary by state.) And, as of today, I estimate that at least 75% of our vehicle miles are now powered by electricity.
Throw all that into a calculator, and you’ll find that the decision to buy a Prius Prime instead of a regular Prius results in an average cost of about $250 per ton of C02 emissions avoided. (Ignoring the Federal tax credit, and using the carbon-intensity of the Virginia grid, which is now somewhere around 0.7 pounds C02 per KWH.)
In short, we had an every-day opportunity to purchase a reduction in our carbon footprint for $250 a ton. Or about one-eighth the cost of reducing the Town of Vienna’s carbon footprint by diverting leaves from far-away Loudoun Composting to the much nearer I-66 solid waste transfer station.
Changing from a conventional Prius to a plug-in hybrid has been odd experience. At first, electrical transport was unsettling. The car goes whir instead of vroom. And “Honey, did you remember to plug in the car?” did not quite sound normal, somehow.
But after just a few months, it’s now the electrical portion of the car that seems normal, and it’s unsettling to have to deal with the gas engine.
Last week, we filled the gas tank, and almost had to get the owner’s manual out to do it. The last time we’d gotten gas was October 2021. Both of us had forgotten where the release button was for the fuel filler door. All things considered, if that’s our worst problem with a (mostly) electric car, I’d have to judge this a success.
Yeah, the paragraph above is just so much humble-bragging. But I hear so much whining about how difficult it is to go electric, that at some point, I think there’s value in saying nope, it’s not. If my wife’s Prius Prime has taught me anything, it’s that you can slide from old-fashioned gasoline-powered transport to electrical transport and not miss a beat.
Plus or minus forgetting where you put the gas in the car.
But wait, there’s more …
Above, I focused solely on the capital cost. But if I’m talking about costs, I forgot about the operating cost, that is, the cost of the fuel. As in, the stuff that actually makes the car run.
Duh. And as gas prices go up, against a constant-to-declining price of electricity … you can probably fill in the rest.
For 150,000 miles, at about 50 MPG, a standard (non-plug-in Prius) would use 3000 gallons of gas. At today’s average U.S. cost of …
Source: AAA.com
… let’s call that $US 4.25 per U.S. gallon, if I were to drive three-quarters of that lifetime vehicle mileage on gasoline, that amounts to $9600 in gas.
But if I substitute three-quarters of that for electrically-drive transport, the fuel cost is far lower.
I pay roughly $0.15 per KWH from my power provider, Dominion Power. That’s the all-in rate, including (e.g.) all fixed costs and distribution charges. The Prius Prime seems to get somewhere between 5 and 6 miles per KWH, as I drive it. And so, if I drive three-quarters of the expected vehicle lifetime on electricity, that amounts to $3375 in electricity.
Th upshot is that my $3600 investment in PHEV (plug-in hybrid electric vehicle) nets me an expected total cost saving … let me say that again … saving … of about $6000 in fuel cost over the life of the vehicle.
And so, for those of you capable of doing simple math, and familiar with the “lifetime-cost-of-ownership” concept, converting to electrical auto transport doesn’t cost me anything. Even ignoring the Federal tax subsidy, it pays me to convert.
My $3600 investment in a bigger battery for the Prius, converting it into a plug-in Prius Prime, results in a net reduction in the lifetime cost-of-ownership of a little over $2000. That’s the $3600 higher capital investment up front, less the lifetime fuel cost savings of $6000 at current prices.
No-brainer, indeed.
I can’t quite figure out why PHEV (plug-in hybrid electrical vehicle) isn’t a more popular option. It minimizes the use of the expensive new component (the battery). It means you have no range anxiety. It means that a standard 20-amp household circuit can recharge your car in a few hours. And it saves you thousands of dollars, to boot.
Why on earth PHEV doesn’t dominate the new car market, I just cannot understand.
