uke

+1. I'd like a Prius, but I'm under no illusions that it would be anywhere near as efficient as my bicycle. It would be, first and foremost, a convenience.

adamtki

Lots of people are posting about how they would've worked out anyway, how its energy intensive to build a Pruius, how food is free, yada yada yada... All that misses the question asked here. Is cycling only twice as efficient energy (or produces half the CO2?) as a Prius for every mile they travel?

I think one question that needs to be answered to help with that is - what does our body do with the extra calories in the food we eat? Does ALL of it get stored or do some of it go straight through (since we have enough)?

I can believe that you can claim to eat the same amount whether you cycle or not if the execess calories go straight through. On the other hand, if our bodies store ALL the calories and fat, then over time, I think cycling will cause us to eat more.

I actually think it's somewhere in the middle.... But I'm no doctor to know exactly how our bodies process food. So cycling is not as efficient as we initiallly thought but it's probably better than twice the efficiency of a Prius.

Treespeed

But you can't just pick and choose which calories to count. If you are going to count the calories burned in creating and transporting food to a cyclist, then you need to count the calories that go into transporting fuel to the Prius. You also need to look at the life cycle costs of creating a car and transporting across the ocean compared to the same costs for a bicycle.

If it makes Prius drivers feel better about their vehicle choice that's great for them, but they are deluding themselves by only looking at a segment of the statistics. It's the same as looking at the fuel costs of a jet cruising at altitude and ignoring the fuel it takes to get the plane to 30,000 feet.

Mr Danw

does the prius driver not eat?

cooker

Miles per gallon is a common way to assess cars.

zeytoun

That's missing the point.

If we're just basing on miles per gallon, that we compare the mpg of the car to the mpg of the cyclist.

A gallon of gasoline has the equivalent of 31,000 calories of food. And most estimates put cyclists at 500-1000 miles per 31,000 calories (less for TDF riders competing, naturally, and more for someone just puttering around a flat neighborhood).

---

Treespeed's point is that, if you start assessing the energy it takes to grow and transport the food that feeds the cyclist, then you need to do it across the board, and calculate the energy it takes to harvest the crude oil and refine it and ship it to the Prius driver.

Szczuldo

exactly my response when I first read the OP..I'm shocked no one else has mentioned it.

On top of that I also realized this post has 7 pages of what probably is ridiculous babble about how much energy it takes to grow potatoes and cows compared to how much energy it takes to get crude oil into gasoline.

feba

This could be true, depending on how the meat is grown (your uncle Ted's farm, or that deer he shot last week are going to have much lower carbon footprints than a factory farm; and the same applies to a Victory Garden vs. a cornfield somewhere in Iowa) and how much driving is done. Also depends on the initial construction footprint (SUV obviously higher there, but it could be bought used; and whether or not you want to count that...)


In general, though, meat takes a lot of energy. Let's use cows as our example. Let's completely ignore the whole 'Methane farts' thing, simply because nobody wants to argue over how bad farting is for the environment. In order for that cow to become a burger, it has to be maintained (at a bare minimum) for quite a few years. That requires machinery for various tasks, but more importantly it requires a huge amount of food. I haven't seen the statistics in a long time, and your best place for looking them up would probably be vegan sites (and PETA), but I clearly remember reading that if all the food that was fed to cows were fed to humans, the idea of (global) hunger would be insane, and food prices would be incredibly low.

Disregarding humanitarian concerns, though, all of that food requires growing. Once it's grown, it could be fed to humans just like that, and probably feed quite a few more humans quite a bit longer than a single cow. So anyway, this cow is constantly eating energy for all the time spent raising them. Of course, a lot of that energy is being crapped out, and a few farms are starting to reclaim that energy, but thanks to physics there is still always going to be a net loss of energy there.

After however many months or years it takes to raise them, they have to be shipped to the slaughterhouse. However far away that is, that's energy spent transporting them. Once they're there, it takes even more energy to run the machinery to slice, dice, Julian fry them, and prepare them for human consumption. After that, they have to be shipped to your local grocery store (which depending on the type of meat and where you live could be a huge cost compared to vegetables which can be grown locally). Once there, they generally have to be kept in freezers ("Non-frozen" food can get surprisingly cold.), and then of course they generally have to be kept in cold storage once they are brought home, until they are prepared for eating.

Compared to that, vegetables will of course need machines to process them, but I believe most of them take significantly less energy to process, in terms of calories, pounds, volume, or whatever else you want to go by, than cattle would. In a grocery store and at home, they can generally be kept at room temperature. If they are kept in cooling, a fridge or cooler is usually more than sufficient. There are of course frozen vegetable, but that is a consumer luxury, not a necessity.

Most of the people I've met who are vegans or vegetarians nowadays actually made that decision for economic or environmental reasons, not animal rights ones. I did too, for awhile (life made that inconvenient, but I have been hoping to go back to it, or at least significantly reduce my meat intake).

EDIT: Oh, and see https://en.wikipedia.org/wiki/Cow#Environmental_impact

Leiniesred

Cows can eat grass. I can't eat grass, but I can eat cows.

Treespeed

But a very simplistic way to look at total energy usage, especially lifecycle energy usage in regards to comparing such very different modes of transport. When discussing global energy impact to not take into account the lifecycle costs of toxic battery packs is disingenuous to say the least. Ten years from now I will still be riding my steel framed Surly, there will be very few original Prius that have not gone through multiple battery packs by then, countless oil changes, etc. The energy and materials goiing into a years worth of tires and oil for a Prius would create a lifetime of such for a bicycle. This is just nonsense, and can be especially proven by having the Prius driver push their car over their commute and compare the energy output to me riding a bike over the same distance.

John Hunt

Is she also counting how much a Prius owner eats.........?

BBnet3000

an incredible amount of energy is lost every time you go up the food chain.

hence the "the earth can support 50 billion vegetarians and 10 billion meat eaters" analysis (i pulled those numbers out of my ass, but i think its currently estimated as something like that)

irregardless, someone should also point out that a lot of people who bike commute dont work out much on the side, wheras people who drive everywhere also have to drive to the gym... bike commuting is athletics, with a purpose besides sport.

Treespeed

[QUOTE=BBnet3000;7526879]an incredible amount of energy is lost every time you go up the food chain.

QUOTE]

Rangeland that can support cattle, or sheep doesn't always translate into farmland.
Plus, millions of people aren't just going to become veggies no matter how "green" it is.

ItsJustMe

Yes, but an incredible amount of "tasty" is gained.

Doohickie

Maybe the Prius guy is right, but in my case the food's already onboard. I'm trying to lose weight, so I'm actually eating less and riding more.

cyccommute 

You need to also include the energy needed to mine the minerals used in making the Prius and its parts, the energy of refining the minerals and making products out of them,t he energy of assembly and shipping the parts, the energy of shipping the Prius (rail, ship and road), the energy of shipping and handling of the used batteries, recycling energy of the batteries, energy of disposal and recycling of the Prius at the end of its use, etc.

Those energies are there for a bicycle too but at a far lower level.

cyccommute 

Often it is even undesirable to even try to make range land into farmland. See, for example, Dust Bowl

In fact, the downfall of the Great Plains was the removal of the American Bison. Bison utilize rangeland about 3 times more efficiently than European cattle do. Removing them resulted in overgrazing by an animal who had not evolved to the unique conditions of the Great Plains.

Pig_Chaser

arrrg irregardless

leadchucker

And don't forget the 'consumables' like, air filters, oil filters, tires, windshield wipers, batteries, etc, etc... those all have to be manufactured, shipped, etc. The number of 'consumables' for an auto are far higher than for bicycle, and the energy needed for their manufacture, shipping, etc, is also far higher.

ItsJustMe

"Irregardless" means the opposite of "regardless" - it clearly SAYS "not regardless" - so it's a synonym for "Regarding that..."

Similarly, "I could care less" means they actually DO care about the point in question. That is exactly what they just said, after all.

Also, "the dog wagged it's tail" means "the dog wagged it is tail" - whatever that means. As a friend of mine likes to say, "an apostrophe is not a warning that an S is coming."

cooker

You guys are so pedantic...and wrong.

"Irregardless" does not mean the opposite of "regardless". It means exactly the same thing as "regardless". It is a non-standard word, frowned upon by purists, but it is not a misuse of a word that means something else. If either of you ever use the word "unravel": now there is a wrong usage. "Ravel" originally meant "to come apart" so "unravel" should really mean "to put together". And the fact that "irregardless" has "ir" at the beginning means nothing. "Flammable" means the same as "inflammable" after all.

"I could care less" and "I couldn't care less" both mean "I don't care". One is hyperbole and the other is irony. "I could care less" is best understood as having an implied "Like" or "As if" in front of it. As if you care.


Now this is a good point. "Its" and It's" are both correct but have different meaning so it is appropriate to distinguish between them.

Febs

https://en.wikipedia.org/wiki/Sarcasm

cooker

Irrecareless.

annc

It had been a rough day, so when I walked into the party I was very chalant, despite my efforts to appear gruntled and consolate.

I was furling my wieldy umbrella for the coat check when I saw her standing alone in a corner. She was a descript person, a woman in a state of total array. Her hair was kempt, her clothing shevelled, and she moved in a gainly way.

I wanted desperately to meet her, but I knew I'd have to make bones about it since I was travelling cognito. Beknownst to me, the hostess, whom I could see both hide and hair of, was very proper, so it would be skin off my nose if anything bad happened. And even though I had only swerving loyalty to her, my manners couldn't be peccable. Only toward and heard-of behavior would do.

Fortunately, the embarrassment that my maculate appearance might cause was evitable. There were two ways about it, but the chances that someone as flappable as I would be ept enough to become persona grata or a sung hero were slim. I was, after all, something to sneeze at, someone you could easily hold a candle to, someone who usually aroused bridled passion.

So I decided not to risk it. But then, all at once, for some apparent reason, she looked in my direction and smiled in a way that I could make heads or tails of.

I was plussed. It was concerting to see that she was communicado, and it nerved me that she was interested in a pareil like me, sight seen. Normally, I had a domitable spirit, but, being corrigible, I felt capacitated--as if this were something I was great shakes at-- and forgot that I had succeeded in situations like this only a told number of times. So, after a terminable delay, I acted with mitigated gall and made my way through the ruly crowd with strong givings.

Nevertheless, since this was all new hat to me and I had no time to prepare a promptu speech, I was petuous. Wanting to make only called-for remarks, I started talking about the hors d'oeuvres, trying to abuse her of the notion that I was sipid, and perhaps even bunk a few myths about myself.

She responded well, and I was mayed that she considered me a savory character who was up to some good. She told me who she was. "What a perfect nomer," I said, advertently.

The conversation become more and more choate, and we spoke at length to much avail. But I was defatigable, so I had to leave at a godly hour. I asked if she wanted to come with me.

To my delight, she was committal. We left the party together and have been together ever since. I have given her my love, and she has requited it.

andrelam

You have to look at full lifecycle cost to have any sort of reasonable comparison. Anything short of a full comparison is completely bogus.

For instantance: I could build a full self sustaining house of 20,000 square feet. It would cost an absurd abount of money and take an absurd amount of energy to build. The owner could claim, look at me, I am living on no net energery comsumption... so my house is better than your 1950's 1000 square foot house that could use more insulation, better windows and a higher efficiency furnace. Saying the huge proposed monster of a house is engery efficient to operate would be true, but you just can't ignore what went into it to building it. The same is true of cars vs. any other sort of transporation.

My 5 mile commute is a perfect example where a hybrid is not all that great. The car still have to warm up. During the 1st few miles a gasoline engine is not very efficient. During the Winter I need ZERO time to warm up on my bike. I just get on and ride. I would love to know how much energy it took to get the car comfy for the rider on those 2F to 15F days we had for a few weeks last Winter. For that matter, in the middle of Summer, the Prius owner better never use the A/C either on those hot muggy Summer days. How many Watts of electricity does that A/C system use. Then there is the electricity that is "waisted" on the daytime running lights. OK I have a generator hub on my bike and have my lights on all year round. I know I generate/use 3 Watts. I guarantee you can't even light up the dashboard on a Prius with 3 watts @ 6 Volts that I generate while riding. The driver also better not use the wind shield wipers, those motors use quite a bit or energy as well. How about the use of the rear defroster on those chilly Fall and Spring mornings. How about clearing the rear view mirrors of condensation or worse yet snow and ice. Defrosters are nothing more than electic heaters... that is going to use quite a bit of energy. The driver better not listen to the radio, because that too uses energy to operate. The driver better sit still and not move. If they move, they will be burning unwanted energy and that would be bad for the planet.

You could go on and on with the silly comparison. As far as I can see it life cycle energy cost is THE most important way to compare. If a Prius owner realy want to save the planet then there are two things they should do:
1. Do NOT reproduce - Putting an other human on the plant will lead to a huge amount of energy to be consumed in a lifetime.
2. Commit suicide (think Logan's Run). In order to not waste any more fossil fuel or "food energy", the environmentally concious person should just end it all and do the planet some good. The person should not be buried or cremated as both would take additional engergy. The body should just be left right where they died so that their bodies can become food for scavengers, and eventualy all kinds or macro and micro scopic life forms can be fed.

OK I am not serious, but you can take any one of these agruements to the rediculous level. What I can tell you is that after I started commuting to work on my bike the following happend:
1. My car is now parked 5 to 6 days a week. I have gone from driving nearly 25,000 miles a year, down to about 9,000 last year. About 1/3 of that mileage was for a family camping vacation, so I am now driving about 6,000 per year. Sure it took a lot of ernergy to make my car, but driving it less uses less energy. I hopefully will also get many more years of use out of the car as it gets far fewer miles.
2. I stopped my Gym membership as I certainly don't have to drive to a club to Spin. I get plenty of that on my daily commute.
3. I will not go out shopping during my lunch break as it takes too long to get to the stores. This is good for a few reasons. A. I prevent wasted mileage. B. I am not buying more "stuff" that I probably didn't need anyways.
4. I eat about the same on a daily basis as I did before I started to ride, but I am now about 10 Lbs lighter. On a day with a long ride I am certainly going to eat a bit more, but before I went to the guy to work out so the extra food argument is kind of a wash.
5. My blood pressure is down from being borderline bad to being normal. The good thing is that I won't need any meds (what kind of energy does it take to make and ship those?). The bad news is that I might live longer... and that could be bad for the planet

Happy riding,
André