atdlzpae Posted October 7, 2019 Share Posted October 7, 2019 3 hours ago, Retrovertigo said: the transport that has the third least impact on the environment after walking and cycling I'm pretty sure PLEV's are the first, before walking and cycling. It's way less impactful/cheaper/easier to generate 1kWh in the form of electricity. And prices reflect that - 1kWh in food (2 chocolates) == $2 while 1kWh in electricity == $0.15. Add a fact that electric engines have like 90% efficiency, while human body has around 25% and the difference is staggering. ###################### According to a random "walking calorie calculator" my calories per 50km is 5500kcal. One charge of MSX is around 2kWh. So about 3 times less CO2 and way cheaper energy source. :-) Bicycle is better, but still worse - 2800kcal per 50km. And requires way more square meters in soil than an equivalent solar panels. 2 Quote Link to comment Share on other sites More sharing options...
LanghamP Posted October 7, 2019 Share Posted October 7, 2019 I would guess PEV are far less energy efficient than walking or bicycling, if the cost of construction is included. Batteries are energy and material intensive, and realistically we're not recycling lithium ion batteries but landfilling them, with all the exigent environmental consequences that entails. 1 Quote Link to comment Share on other sites More sharing options...
Chriull Posted October 7, 2019 Share Posted October 7, 2019 11 hours ago, atdlzpae said: I'm pretty sure PLEV's are the first, before walking and cycling. It's way less impactful/cheaper/easier to generate 1kWh in the form of electricity. And prices reflect that - 1kWh in food (2 chocolates) == $2 while 1kWh in electricity == $0.15. 100g chocolate has about 550 calories. Thats about 550*4.18 Joule(=Ws)~2300Ws=0,64Wh. (1kcal ~1.16 Wh=0.00116kWh) So 1kWh of chocolate would be about 150kg... Quote Add a fact that electric engines have like 90% efficiency, while human body has around 25% and the difference is staggering. Electric engines can have about 90% efficiency (and above) - at a specifique load and rotational speed. Beside this maximum efficiency gets quickly to "horrible" numbers - as we have widely varying torque and rpm values with the EUC the efficiency is mostly/in average way below 90%. Additionally there is the efficiency of the controller and the li ion batteries and the charger and charging to be considered. Quote ###################### According to a random "walking calorie calculator" my calories per 50km is 5500kcal. One charge of MSX is around 2kWh. So about 3 times less CO2 and way cheaper energy source. :-) So 50km walking burn 5500kcal~6.3Wh ~ 1kg of chocolate (maybe not the most efficient way to "fuel" the body for walking with chocolate...) And with your above number of 25% efficiency this would mean ~4kg chocolate for 50km walking... I would not go anywhere but to the hispital after 4kg chocolate - i'd assume the human body works very different... (Or i had some faults in my calculations, too...) Quote Bicycle is better, but still worse - 2800kcal per 50km. And requires way more square meters in soil than an equivalent solar panels. That's about 3.2Wh - imho a great number - and 50km biking a day is about feasable, with normal food consumption... 1 Quote Link to comment Share on other sites More sharing options...
Kens Posted October 7, 2019 Share Posted October 7, 2019 4.5 kg XXL Toblerone chocolate bar for scale.. Now how much calories did I burned to read this topic? Quote Link to comment Share on other sites More sharing options...
Seba Posted October 7, 2019 Share Posted October 7, 2019 1 hour ago, LanghamP said: I would guess PEV are far less energy efficient than walking or bicycling, if the cost of construction is included. Batteries are energy and material intensive, and realistically we're not recycling lithium ion batteries but landfilling them, with all the exigent environmental consequences that entails. But if you include environmental impact of food production & distribution, things are getting more complicated. And lithium ion batteries are more and more often reused in energy storage systems, especially in EV charging stations. 1 Quote Link to comment Share on other sites More sharing options...
atdlzpae Posted October 7, 2019 Author Share Posted October 7, 2019 (edited) 1 hour ago, Chriull said: 100g chocolate has about 550 calories. Thats about 550*4.18 Joule(=Ws)~2300Ws=0,64Wh. (1kcal ~1.16 Wh=0.00116kWh) So 1kWh of chocolate would be about 150kg... 100g of chocolate has about 550,000 calories. ;-) So 1kWh of chocolate would be about 150g. 1 hour ago, Chriull said: So 50km walking burn 5500kcal~6.3Wh ~ 1kg of chocolate (maybe not the most efficient way to "fuel" the body for walking with chocolate...) And with your above number of 25% efficiency this would mean ~4kg chocolate for 50km walking... 5500kcal == 1kg of chocolate is for walking while hauling 120kg of fat - it already includes all inefficiencies. So I'd need to eat 1kg of chocolate, not 4kg to be energy neutral. Edited October 7, 2019 by atdlzpae 1 Quote Link to comment Share on other sites More sharing options...
Chriull Posted October 7, 2019 Share Posted October 7, 2019 2 hours ago, atdlzpae said: 100g of chocolate has about 550,000 calories. ;-) So 1kWh of chocolate would be about 150g. chocolatinterestinz. Google search shows 540 calories for 100g. The wikipedia article shows 540kcal for 100g (candies/milk chocolate) according to "Full Link to USDA Database entry" and mentions 540 calories for 100g in the next paragraph again... The USDA database shows 535kcal again... Also the serious sites with calorie tables... I should learn to not thrust google search... ... Seems to be messed up in the internet.... So the factor 1000 is solved (for me) i take everything back and Claim the opposite 3 hours ago, Chriull said: 5500kcal~6.3Wh And here 6.3kWh.... Quote Link to comment Share on other sites More sharing options...
Mono Posted October 7, 2019 Share Posted October 7, 2019 3 minutes ago, Chriull said: chocolatinterestinz. Google search shows 540 calories for 100g. The wikipedia article shows 540kcal for 100g (candies/milk chocolate) according to "Full Link to USDA Database entry" and mentions 540 calories for 100g in the next paragraph again... The USDA database shows 535kcal again... Also the serious sites with calorie tables... I should learn to not thrust google search... ... Seems to be messed up in the internet.... It's just that in the context of food, calories (AKA food calorie or large calorie, abbreviated as Cal) refers to kcal, see https://en.wikipedia.org/wiki/Calorie 1 Quote Link to comment Share on other sites More sharing options...
Mono Posted October 7, 2019 Share Posted October 7, 2019 15 hours ago, atdlzpae said: I'm pretty sure PLEV's are the first, before walking and cycling. I agree, with the caveat that the environmental impact of batteries is fairly difficult to judge. And I would think that cycling is second before walking. 1 Quote Link to comment Share on other sites More sharing options...
LanghamP Posted October 8, 2019 Share Posted October 8, 2019 2 hours ago, Mono said: I agree, with the caveat that the environmental impact of batteries is fairly difficult to judge. And I would think that cycling is second before walking. A bicycle is about five times more efficient than walking. I'm probably in the minority, but I consider the bicycle to almost be Man's greatest achievement. "When man invented the bicycle he reached the peak of his attainments. Here was a machine of precision and balance for the convenience of man. And (unlike subsequent inventions for man’s convenience) the more he used it, the fitter his body became. Here, for once, was a product of man’s brain that was entirely beneficial to those who used it, and of no harm or irritation to others. Progress should have stopped when man invented the bicycle.” Elizabeth West, ‘Hovel in the Hills’ 1 Quote Link to comment Share on other sites More sharing options...
Mono Posted October 8, 2019 Share Posted October 8, 2019 7 hours ago, LanghamP said: A bicycle is about five times more efficient than walking. Taken into account the bicycle production? What's the assumed lifetime mileage? Quote Link to comment Share on other sites More sharing options...
Seba Posted October 8, 2019 Share Posted October 8, 2019 (edited) 11 hours ago, Mono said: And I would think that cycling is second before walking. I think this is out of question Cycling allow to use the same energy in much more efficient way. Edited October 8, 2019 by Seba Quote Link to comment Share on other sites More sharing options...
Mono Posted October 8, 2019 Share Posted October 8, 2019 (edited) 31 minutes ago, Seba said: I think this is out of question Cycling allow to use the same energy in much more efficient way. Same question: how do you take into account the production of the bicycle? Or, in other words, what is the break even mileage where walking and cycling have the same balance lifetime efficiency? If we cannot answer this question we can't possibly know whether cycling or walking is more efficient overall. Edited October 8, 2019 by Mono 1 Quote Link to comment Share on other sites More sharing options...
LanghamP Posted October 8, 2019 Share Posted October 8, 2019 5 hours ago, Mono said: Same question: how do you take into account the production of the bicycle? Or, in other words, what is the break even mileage where walking and cycling have the same balance lifetime efficiency? If we cannot answer this question we can't possibly know whether cycling or walking is more efficient overall. A single speed bike is cheaper than five pairs of shoes, while its tires last several thousand miles. Even its sunk cost isn't precisely sunk because you can always sell a bicycle that isn't completely rusted out, while the same cannot be done with used shoes. A single speed costs between $50 to $100, requiring tire replacement every 2000 miles. New shoes cost $10 (you shop at Aldi), and wear out every 100 miles, so the break even cost is around 500 to 1000 miles. 1 Quote Link to comment Share on other sites More sharing options...
Mono Posted October 8, 2019 Share Posted October 8, 2019 (edited) 3 hours ago, LanghamP said: A single speed bike is cheaper than five pairs of shoes, while its tires last several thousand miles. Even its sunk cost isn't precisely sunk because you can always sell a bicycle that isn't completely rusted out, while the same cannot be done with used shoes. A single speed costs between $50 to $100, requiring tire replacement every 2000 miles. New shoes cost $10 (you shop at Aldi), and wear out every 100 miles, so the break even cost is around 500 to 1000 miles. Right, I had more thought about energy/environmental efficiency, as the OP seems to suggest, but I guess cost is a reasonable zero order approximation. Edited October 8, 2019 by Mono Quote Link to comment Share on other sites More sharing options...
LanghamP Posted October 9, 2019 Share Posted October 9, 2019 On 10/8/2019 at 2:32 PM, Mono said: Right, I had more thought about energy/environmental efficiency, as the OP seems to suggest, but I guess cost is a reasonable zero order approximation. I was surprised to see how destructive mining for minerals is. Basically, you use a bunch of chemicals to extract minerals from stone, and then try to store that contaminated solution in a toxic lake, which invariably leeches out or overflows. I was reading about Montana's extraction industry which for every dollar the mining industry makes, ten must be spent just in cleanup costs. So bicycling can be dirty but one could just use a very small amount of aluminum, I would think. Walking would use less materials initially. Interestingly, most micro plastic waste (what all plastics eventually end up as) is from automobile tires being used up, so all the plastic conservation is probably doing hardly anything. Although that study is the Bay Area, I'm sure other places will soon find out their plastic pollution is even worse because they drive more miles, have more cars, and drive faster. My opinion is that any micro transport will be minimal is both energy and environmental impact. Quote Link to comment Share on other sites More sharing options...
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