spare_wheel

LCA for driving my nissan leaf using PGE Green Source power versus cycling:

Car
~70 g CO2e/km for electric vehicle manufacturing
~3 gCO2e/km for charging including grid infrastructure (Portland Green Source offsets -- 98% wind 2% geo/solar)
https://shrinkthatfootprint.com/electric-car-emissions

https://ec.europa.eu/transport/themes...fic_study).pdf


Bike

~130 g CO2e/km (assuming ~50 calories burned per mile and the average diet) A meat-centric diet would increase that footprint hugely.
My diet (vegan): ~78 g CO2e/km

https://shrinkthatfootprint.com/shrin...food-footprint

I'm kind of blown away that I likely generate more CO2e biking to work than I would driving to work.

79pmooney

But, if you add to the electric grid and the available hydro and wind power is being used to the max, the additional energy that you are using is coming from the Boardman coal facility. That puts CO2e/km levels right about where regular cars are. And that facility is none too clear for other emisions. Ever driven by it? (Irony, the only time I have is to get to Cycle Oregon.)

Electric cars are not a free ride. It just leaves the problem on someone else's doorstep. (Maybe when we are completely electrical energy eco friendly but that is a long way off.)

Ben

fietsbob

And in a Coal powered Grid , there is that power-plant carbon footprint,
and dont forget Bikes have a pretty large carbon footprint in transportation, not just the high sulfurous Bunker Oil the ships Burn crossing the Oceans

but all the cardboard and plastics used to box & wrap them Up, so to be scratch free for the show room floor..

spare_wheel

Currently, all my kwh are offset using blocks of energy purchased from the following sources:

Sources | Green Power Oregon

IMO, the source at a particular time does not matter as long as I'm replacing my total usage with offsets.

The offsets are approved by the public utility board and are audited by a 3rd party based on DOE standards.
Welcome to Green-e!

And even if I were to use normal grid energy without offsets, coal only accounts for 22% of electricity while non-hydrocarbon sources represent about 40% with the rest being natural gas. This would likely only add ~130 g CO2e/km based on the shrinthatfootprint.org LCA.

I disagree. In a few years boardman will close and over 50% of PGEs energy production will likely be non-hydrocarbon (based on planned renewable sites). The rate at which PGE is adding wind energy generation is simply astonishing and I expect we will approach 70-80% non-hydrocarbon in less than a decade (especially given accelerating conservation).

rockmom

How are you calculating 50 calories per mile? Is that total calories burned per mile, or net after subtracting calories burned while driving?

wolfchild

I am not one of those paranoid global warming alarmists and I don't really care or worry about GHG or climate change.

Roody

Preposterous. You're not "generating" CO2 when you ride your bike. You are at most recycling carbon from a solid (food) to a gas (your exhaled breath) as part of the carbon cycle. There is no long-term net gain or loss of free carbon involved in the process. The amount of CO2 breathed out by all the people and animals of the world are easily converted back into solid carbon through photosynthesis by plants.

Climate change is a result of freeing sequestered carbon from some other source into the atmosphere. As far as I know, the only way to do this is to dig the carbon out of the ground and pump it into the atmosphere--achieved by burning fossil fuels. Therefore, your car does burn carbon fuels, your bike (you) does not. The carbon relaesed by burning fossil fuels exceeds the capacity of photosynthesis. Therefore it remains in the atmosphere and contributes to climate change.

Roody

No, you're just ignoring the problem and leaving it to your children and grandchildren. What a guy!

spare_wheel

Sadly, you are mistaken. Agriculture is a major contributor to ACC and one of the largest contributors is methane (represented above as CO2 equivalents -- CO2e).

spare_wheel

Good point. Estimates for calories consumed while driving range from 3-5 CO2e per km and this should be subtracted. I should note that 50 kcals per mile is a low ball estimate for me...I ride very fast and have a 1000 foot elevation gain.


I should note that I personally have no need to drive and commute by bike every day. Moreover, the LCA analyses I linked to likely do not capture the decrease in CO2e due to better health. (Healthcare has an enormous GHG footprint.)

B. Carfree

Two things: first off, the so-called renewable power sources do have emissions, sometimes substantial. Those dams cause substantial methane production, for instance. Locally, we have a log burning plant that is officially classified as renewable power, but involves massive burning of fossil fuel from harvest to transport (not to mention the damage done by the particulate pollution it produces). I'd like to see a very detailed and honest accounting of the total emissions of the electrical power.

Secondly, on the emissions of cycling, that's kind of BS. A human body requires exercise in order to maintain health. The fact that one can get that exercise while meeting one's travel desires and needs isn't an increase in emissions, it's just making a sensible choice in how to get the required exercise.

Roody

Again, the methane (cow farts) are not net increases in the daily fluctuating amounts of carbon in the atmosphere. It's a feedback thing called the carbon cycle. You should read up on it if you're serious about decreasing your carbon footprint.

As for synthetic fertilizers and fuel used in industrial agriculture--which do increase net atmospheric carbon--are you planning to quit eating when you drive your car? If the carbon footprint of food is something that truly concerns you, I suggest that you quit eating meat, grow your own food, and buy organic food whenever possible.

wphamilton

The CO2 that we breath out is already accounted for in the global balance sheet because it is part of a closed cycle. It was already there in the air before being captured by the plants and converted by photosynthesis, which we return to the air.

prathmann

This would be true if you were getting all your food from naturally growing plants or by catching wild animals. But most of us eat food that's grown on farms where they use lots of 'sequestered carbon' in the form of fuel for the equipment on the farm and to transport it to markets, plus all the fertilizer/pesticides/herbicides used, and additional energy when the food is processed/packaged/etc.

When I ride instead of drive I definitely increase my appetite and eat considerably more food which does require fossil fuels to produce and get to my grocery store.

Roody

Look at it this way. If you did not eat the food, what would happen to it? It would either rot, be burned, or be eaten by somebody else. In any of those cases, the carbon in the food would be emitted to the atmosphere--just the same as if you had eaten it.

What if the food you would have eaten when riding your bike was never even grown? Then the land that the food was grown on would have been uncultivated and covered with native forest or grasslands. The wild plants that grow there would eventually die. At that point, they would either be eaten by animals, decomposed by microorganisms, or burned in a wildfire. In any case, the carbon in these wild plants would end up being emitted into the atmosphere--exactly as they would have been if you had eaten them!

The point is, there is no NET gain or loss in total carbon as a result of eating food. The carbon constantly fluctuates between temporary storage in plants and temporary release into the atmosphere by breathing organisms. This is a very beautiful thing called the carbon cycle, which has been occurring on Earth for billions of years now.

ESRL Integrating Research and Technology Theme: Carbon Cycle Science

Roody

The answer is not to drive a car, which does result in a net increase of CO2 from burning fossil fuels. The answer is to reduce the footprint of your eating habits. Reduce meat consumption, grow your own food organically, and select organic food at the market. I know that's hard to hear, I do love my burgers.

The food we eat probably has a greater impact on AGW than even the transportation we use. IOW, you're probably helping the environment more by becoming vegetarian than by becoming carfree.

But in any case, to say that bikes pollute more than cars is one of the silliest things I've ever heard. And the irony is--the only place I've ever heard it is on this so-called carfree forum!

spare_wheel

You are quite mistaken about methane not having an enormous impact.

Umm...perhaps you should re-read my original post where I state that my diet is vegan (and has been for most of my life).

And I strongly disagree that organic food makes sense from an environmental pollution perspective. Any agricultural system that relies on manure inputs that depend on petro-fertilizer animal feed is not sustainable. If the organic movement allowed nitrogen input synthesized using renewable energy I would be more supportive but, by definition, it does not. Hopefully this will change.

spare_wheel

The ec LCA I cited attempted to account for additional emissions caused by renewable power generation. I also found some specific studies that measured CO2e associated with renweables and the additional emissions were low. I'll add links when I have more time.


As to your second very good point it echoes the point I made previously:
I would love to see someone attempt to account for the improved efficienies of combining exercise with transport...

Roody

Again, all that fancy math and no understanding of the basic carbon cycle. It's all about digging carbon out of the ground and pumping it into the air.

To drive ANY car requires digging more carbon out of the ground than eating amounts of ANY food to account for incremental increases in metabolism from riding a bike. You have totally lost the forest for the shrubbery.

Of course I do compliment you on your vegan diet, selection of an electric car over internal combustion, and use of the bike for some of your trips. You rock, and I'm sure your carbon footprint is much lower than my own!

Ekdog

There's a pie chart on my bill that breaks down the way the electricity I'm buying is produced. This is the breakdown:

Renewable (wind and solar): 40.6%
High-efficiency cogeneration: 0.5%
Cogeneration: 8.3%
Combined cycle natural gas: 10.4%
Coal: 16.1%
Fuel / gas (?): 2.3%
Nuclear: 20.3%
Others: 1.5%

As I've recently learned that in Spain (and throughout the EU, apparently,) one can choose one's electricity provider, I've switched to a new one that produces 100% of its electricity with wind and solar. Still, I'm convinced that cycling is much better for the environment than driving an electric car, so it's pedal power for me.

350htrr

Cycling is certainly better than electric cars, but electric cars are certainly better than gas/diesel vehicles... This statement may seem obvious I'm sure to most here, but not it seems, to others in general for thing would be different by now...

Number400

A 4 wheeled EV takes up the same amount of space that a carbon burning vehicle does. These IC cars are most inefficient at idle and stop and go traffic. A smattering of EV vehicles won't help reduce anything because they are mixed in and the volume still causes traffic jams. Bikes help to ease that but will only really help if enough people ditch their car for the bike for their commute. If bike traffic was separated from EV traffic and EV traffic separated from carbon traffic it might have an impact. Hybrids are a decent idea but until all cars are electric or hybrid then nothing is going to change. The kicker is that with all the cleaning up of emissions in passenger cars over the years, one person driving a smoky old clunker or one poorly running gas powered lawn mower makes more pollution in an hour than 10 cars do all day. On summer Saturdays around here, there are 2-3 old lawnmowers running on the block at any given daylight hour all day. In the winter, it's snow blowers. All of this needs to change and pretty soon.

79pmooney

Two thoughts: Natural gas is putting stored carbon back into the environment and the process of obtaining a real percentage of the natural gas in the US, fracking, may not add to the carbon load but has a host of other issues. And, choosing one's energy sources, like PGE allows us to do in Portland, allows us to live guilt free while the total energy production methods stay the same. We get to pick the cream of the crop, so to speak, while the big industries care little if their huge electrical consumption is provided "cleanly". As long as the "clean" sources cannot meet all of our collective needs, adding to the grid means more dirty fuels being burned..

I make zero claim to being a saint here. I own a house that two of us live in. A car (Prius), two titanium bikes (ti is a very "dirty" metal) and three (much "cleaner") steel bikes, natural gas heating, hot water and stove. And probably a host of other "sins" I am not thinking of at the moment. (Music played through energy intensive tube amplifiers?)

Ben

CliffordK

As others have mentioned, it is mostly a closed cycle, but fertilizer is produced using petroleum. Tractors generally run with petroleum, and there is also transportation costs. Even water often takes energy.

But, one should calculate the difference between energy consumption as a couch potato vs active athlete. Are you driving your EV to the gym to burn some calories?

The best way to reduce your carbon footprint... is to reduce the number of children.

spare_wheel

and it's also about converting biological carbon into methane and releasing it into the air (among other things). i don't know why you keep on claiming that environmental researchers at shrinkthatfootprint.com (widely regarded as fair -- they publicized the negative footprint of mostly coal-powered e-vehicles) do not understand the carbon cycle. that's patently false and unsupported to boot.

FWIW, The only time I use the e-vehicle is to replace trips that my cohabitant insists should be via car (previously an ICE car). She has also agreed to use the e-vehicle for many of her work commutes. She will drive that car far, far more than I do.