4 ms·

A small notes: everyone seems to imaging eVTOL for cities, but hey, they are not for them at all. Look at https://www.easa.europa.eu/sites/default/files/dfu/uam

• mmooss 1y ago
  > they fails to accept that a condo consume more natural resources to be built than single-family homes and sheds one per apartment/shop in the condo and also more natural resources to evolve. Do you have something we can read about that? If you mean a smaller unit in a denser city, why would it consume more resources? Flying via eVTOL to the neighbor or to the store, compared to walking down the street or down the hall, seems a lot less efficient. Then there's bicycling, public transit ... those all seem more effficient than eVTOL.
  • kkfx 1y ago
    > Do you have something we can read about that? I'm slowly collecting projects of some condos, homes and shed, along with their docs about resources needed to build them. From the little I've examined just the common areas (elevators, stairs, hallways etc consume more than single family homes roofs and perimeter walls. If they are more than 7-8 stories they consume more ALSO to sustain their own structure. AFAIK very little literature exists on that topic, you can find things like https://archive.is/jIr8J https://archive.is/jIr8J or https://www.helsinkitimes.fi/finland/finland-news/domestic/20911-residents-of-helsinki-have-larger-consumption-footprint-than-many-others.html https://www.helsinkitimes.fi/finland/finland-news/domestic/2... etc but nothing more. And that's anyway is just the "building" part alone; aqueduct in cities and wastewater treatments also demand much more resources than small spread aqueducts exploiting from little local sources. Large covered areas means soil consumption due to watertight cover who suffocate the humus of the soil making the soil evolving in sand, creating liquefaction problems like sinkholes and the mere mass subsidence. > Flying via eVTOL to the neighbor or to the store, compared to walking down the street or down the hall, seems a lot less efficient. The fly yes. The energy and resources to build a road, keep it up, evolve it when the climate change makes people move does consume much more. Useful life of the vehicle itself change much (beside the battery) also keep in mind that food is not produced in the store, it need to be moved there and the higher density the greater distance need to be covered moving goods. Making efficient the last mile ignoring the rest of the supply chain is not really green. We are in a changing world, we can't keep up ground infra, a flying vehicle means just ability to move in a certain radius, a ship similarly means ability to move on water for a certain range maximum, roads and rails means being tied to their design or spending immense amount of resources to build new ones.
    • mmooss 1y ago
      If you have any data, that would be great. As far as I know, the research shows that dense cities are far more efficient per person than less-dense suburbs and rural areas. Many more people share resources, there is economy of scale, and because of the density people use much less road to get to the store, work, and dinner - often none at all if they walk or take the train.
      • kkfx 1y ago
        Well, not for now but... But just for a single building how much "supporting infra" you have, meaning raw materials, and how limited heat-pumps heating you can made there. If you extend that for a whole city it's clear that current research just see one aspect, instead of a TCO. It's like "rails are the most efficient ground transport" and that's true, if we count just a single journey an an already made network. Things dramatically changes if we count how much we need to develop and keep up rails, stations, intermodal exchanges and how much we need to change them. It's hard to compute of course, but it's easy to size a bit.