2 HN users recommended this explainer2 months2021–2025score 2
Years with an HN recommendation, 2007–2026
HN commenters cite it in EV and emissions debates for its numbers on when replacing a car pays off.
Engineering Explained compares the lifecycle emissions of keeping an old car with those of buying a new, more efficient one. It weighs manufacturing emissions against emissions from driving, and covers gas versus electric cars.
“Skip to 6 minutes in the video for when he starts showing compiled data of when its better to buy a new car vs keep old.” (HN, 2021)
Engineering Explained youtube channel tackled this question: [this video] The verdict appears to be that the answer to this question is a bit more complicated then a blanket "Its better to buy a new car for the environment" but its highly dependent on gas milage and time of ownership, as well as new gas car vs new hybrid car vs new electric car. He does take into account carbon needed to build the cars too. It seems that in most cases a new EV will be better for the environment then your 10 year old honda in roughly 4 years. Skip to 6 minutes in the video for when he starts showing compiled data of when its better to buy a new car vs keep old.
Compiled data on when buying a new car beats keeping an old one.
A video I watched recently comes to a very different conclusion on almost every point you raised: that buying a new electric car is better for the environment within ~5 years of use, taking into account the 'new car' footprint. I'm not an expert, so I won't claim to know who's correct. But the linked video provides lots of numbers, and you didn't, so I lean in favour of that conclusion. [this video]
Provides numbers showing a new EV pays back its footprint in about five years.
The average age of cars on the road is above 10 years, if I recall correctly. This is plenty of time to rack up enough mileage to offset the carbon cost of manufacturing. Using averages, it seems like replacing a car with average MPG (25) with a car with 35 MPG, it only takes 7 years of driving to be better off CO2 wise. It takes even less for electric cars. I think most people overestimate how much CO2 is produced during manufacturing vs how much CO2 is produced by driving. I'm mostly going off of this video - [this video] Moreover, I don't believe that there is a daily commute that's more than 120 miles each way, and this is well within the capabilities of even reasonably priced electric cars today. If you have a charger at your workplace, you could accommodate even longer trips, however colder weather might make a big dent in the range of most electric cars.
Engineering Explained covered this is a recent video. tldr while it obviously depends on how much you drive, you need a pretty efficient ICE car for sticking to lower carbon overall. [this video]
Concludes only a pretty efficient ICE car beats new on carbon.
I would be curious so see how the Hummer EV compares not based on national average, but in a markets where electricity is not produced via fossil fuels, and in a market where electricity is produced via fossil fuels. Engineering Explained covered this in part, in his video asking whether or not it is better for the environment to keep your current (presumably ICE) car, or buy a new EV. [this video]
Partly covers keeping current car versus buying a new EV.
> From an environmental perspective, I bet I could drive that truck for the rest of my natural life before I consumed more resources or exhausted more pollutants than would be required to manufacture a new one. Unless you drive much less than the avarage this is not true, engineering explained [1] did a video about this, and comparing a 24 MPG to a 35 MPG car you produce more CO2 with the 24 MPG car compared to a new 35 MPG car (including the manufacturing) considering your GMC has much worse fuel efficiency that break even point would be much earlier. This is not even considering the impact of recycling... So the best thing for the environment you could do is buy a new more fuel efficient car. [1] [this video]
Shows a new 35 MPG car emits less CO2 than keeping a 24 MPG one.
Video list and Hacker News comment labels from HackerTube (prompted by @karpathy), released under ODC-By 1.0, built on the open-index/hacker-news archive. Hacker News data is provided by Y Combinator; comments remain the work of their authors. Video titles, channel names and thumbnails belong to their creators and are shown via YouTube. HackerTube Watch is an unofficial edition. Data export of 2026-10-31.
Plays via YouTube's privacy-enhanced embed
7 Hacker News comments
From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.
Read more
Citations, criticism and jokes
Read more
Read more