Walkability/New construction
If walkability was achieved by building brand-new neighborhoods, how long would it take to "break even" considering the carbon emissions of building the new homes/buildings?
Simplified model:
- consider the carbon footprint of making a new building, per person living there.
- assume a full extreme lifestyle change: people go from "USA average" amount of driving, to zero driving.
In such a case, it would take about 7-8 years to pay itself off:
building.construction_ghg_by_floor_area
530.43 kg/m^2
CO2 emissions involved in making a building, per unit of floor area
Includes all materials and construction processes.
But probably doesn't include furnishings.
Source:
Case Study on Carbon Footprint Life-Cycle Assessment for Construction Delivery Stage in China
by Xiaojuan Li, Chen Wang, Mukhtar A. Kassem, Shu-Yi Wu, and Tai-Bing Wei
https://www.mdpi.com/2071-1050/14/9/5180
Sustainability 2022, 14(9), 5180; https://doi.org/10.3390/su14095180
Quote: "...the area carbon-emission intensity is between 400 and 800 kgCO2/m^2, and the average area carbon emission of the building is 647.99 kgCO2/m^2 compared to other research results for emissions around 412.87 kgCO2/m^2"
So I decided to take the midpoint between both figures.
But probably doesn't include furnishings.
Source:
Case Study on Carbon Footprint Life-Cycle Assessment for Construction Delivery Stage in China
by Xiaojuan Li, Chen Wang, Mukhtar A. Kassem, Shu-Yi Wu, and Tai-Bing Wei
https://www.mdpi.com/2071-1050/14/9/5180
Sustainability 2022, 14(9), 5180; https://doi.org/10.3390/su14095180
Quote: "...the area carbon-emission intensity is between 400 and 800 kgCO2/m^2, and the average area carbon emission of the building is 647.99 kgCO2/m^2 compared to other research results for emissions around 412.87 kgCO2/m^2"
So I decided to take the midpoint between both figures.
gasoline.ghg_by_energy
71.30 kg / million btu
CO2 emissions of burning gasoline
https://www.eia.gov/environment/emissions/co2_vol_mass.php
average_us_vehicle.fuel_usage
489 gallons gasoline/year
The average American vehicle uses this much gasoline (measured in energy units)
Top Numbers Driving America's Gasoline Demand
https://www.api.org/news-policy-and-issues/blog/2022/05/26/top-numbers-driving-americas-gasoline-demand
Note: Since the statistic is mentioned specifically in relation to gasoline, we can '''probably''' assume that it excludes diesel-powered vehicles such as semi trucks. But the website doesn't specify that, so it's anyone's guess.
https://www.api.org/news-policy-and-issues/blog/2022/05/26/top-numbers-driving-americas-gasoline-demand
Note: Since the statistic is mentioned specifically in relation to gasoline, we can '''probably''' assume that it excludes diesel-powered vehicles such as semi trucks. But the website doesn't specify that, so it's anyone's guess.
usa.registered_vehicles
275.9 million
Number of registered vehicles in the USA
Top Numbers Driving America's Gasoline Demand
https://www.api.org/news-policy-and-issues/blog/2022/05/26/top-numbers-driving-americas-gasoline-demand
https://www.api.org/news-policy-and-issues/blog/2022/05/26/top-numbers-driving-americas-gasoline-demand
usa.population
334416477 people
Number of people living in the USA
United States Population (Live) - Worldometer
www.worldometers.info › world-population › us-population
Last updated April 7 2022
www.worldometers.info › world-population › us-population
Last updated April 7 2022
home_space
400 square(feet) per person
private_fraction_of_building
70%
Percent of the building's floorspace that is private living space
The rest is hallways, stairwells, and common rooms.
(calculation loading)
The real-life figure might be higher because...
- can't really expect a full change to zero driving, just a lot less than before
- the calculation didn't include interior furnishings of the building, as far as I know
Or it might be lower because...
- the footprint of heating the new place would probably be lower than the old place
In any case, the carbon payoff of new construction could be worth it if there's no better option for Walkability/Existing housing.