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9 votes
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Impact on environment: a million horses vs a million cars

In large numbers, horses are more problematic than cars. According to Eric Morris, in 1898 delegates from around the world gathered to discuss urban planning. The issue they were "desperate" to solve ...
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9 votes

Does it matter where I charge my device?

Yes, it matters, a little, but it also depends on your location. In your car, the process of converting fuel to movement is pretty inefficient (about 25% to 30%, according to this). That movement (...
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7 votes

Can alloy wheels (for a car) pay for themselves through fuel savings?

A quick look doesn't show a clearcut weight difference. The claim is more for a 'rounder' wheel and a 'stiffer wheel' First order approximation fuel economy depends on the weight of the vehicle, ...
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7 votes
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What measures could be taken to decrease the air pollution in a big city?

To encourage people to not use of purchase cars develop a public transportation system that is easily accessible by the to public and caters to the needs of the public so that people will use it. ...
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7 votes
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Does 1 container ship really pollute as much as 50,000,000 cars?

It depends on how you define "pollution". Cargo ships use some of the dirtiest fuels available: bunker fuel is basically what's left over after you refine all the good stuff out of crude oil....
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6 votes

How effective is turning a car's engine off while standing at a traffic light?

I have been using this method for years, on both my Toyota and my Ford Explorer. I save lots of gas, nothing has ever happened to my batteries, and have never had a mechanical problem. You need to use ...
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6 votes
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Does putting an automatic car in neutral when stopped help save petrol?

According to this answer over on mechanics.SE, below a certain engine RPM, your vehicle automatically disengages the torque converter. That is to say, when stopped, there isn't a fundamental ...
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6 votes

To what extent do CO2 emissions from motor vehicles vary?

CO2 is produced by burning the carbon in the fuel, so if your driving style causes you to use twice as much fuel, you will produce twice as much CO2. Driving aggressively can have a big impact on ...
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  • 294
6 votes

Which countries, regions, or cities have set a date to ban the sale of gasoline and diesel vehicles?

The best list is probably wikipedia: Phase-out of fossil fuel vehicles There is a good review from the World Economic Forum here, dated 2017, which discusses some of the different approaches taken, ...
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  • 961
5 votes

Impact on environment: a million horses vs a million cars

I think the main problem is that commuting is almost never "eco-friendly". There's a lot of energy that's needed to carry your behind (and your carriage) from your home to your workplace. I think the ...
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5 votes
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How feasible would a gas-powered electric-engine based car be?

It would work, but there isn't much reason to do it. If you do this without batteries, you are giving up most of the potential advantages. If you simply have an internal combustion engine (petrol or ...
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5 votes
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What is the environmental impact of replacing a vehicle?

According to this reference, up to 12 - 28% of the carbon emissions associated with a vehicles life cycle come from its manufacture and delivery. So starting right now, of the two vehicles, the new ...
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5 votes

Why is the private car still more popular over other forms of transport in the USA?

It is well within any government's power to tax the private automobile into the ground by raising taxes exponentially on the private use of fuel. (...) Not a single major politician, not a single ...
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4 votes
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Why are electrical cars encouraged but is electrical heating discouraged?

There are several reasons why a policy of encouraging electric cars, but discouraging electric heating, might make sense. I can't answer for the specific case of Belgium, which currently has some ...
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  • 14.6k
4 votes

How feasible would a gas-powered electric-engine based car be?

The concept has been used in heavy duty mining trucks for decades. Diesel powered locomotive engines power an electric generator that then powers electric motors located on the rear axles of the ...
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  • 3,207
4 votes

Can chip tuning make a car more fuel-effective?

Yes, many tuning stations offer a range of options. The most popular is to offer power upgrades, usually at the expense of fuel economy, for example improving fuel/air/compression balance at low ...
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4 votes
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How efficient are tiny cars compared to others?

In the USA the Daimler/Mercedes "Smart" Fortwo car is the obvious choice, rated at 41mpg on the highway. Those look silly but are quite safe and very fuel efficient, as well and being ridiculously ...
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  • 3,755
4 votes

What measures could be taken to decrease the air pollution in a big city?

Plant a lot of trees -- assuming you mean partciulate pollution: See for example Estimating the removal of atmospheric particulate pollution by the urban tree canopy of London, under current and ...
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  • 2,037
4 votes
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The more miles a car drives, the more economical battery packs become?

The immediate previous sentence says: The other unknown that BNEF considers is the rise of autonomous cars and ride-sharing services like Uber and Lyft, which would all put more cars on the road ...
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  • 308
4 votes

To what extent (if any) are electric vehicle batteries recyclable?

Li-Ion batteries are worth recycling just for the lithium in them. This material can be re-refined, and made into new batteries. In this use they should show similar cost savings to recycled vs new ...
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4 votes

Are there any unsustainable supply-chain issues unique to hydrogen fuel cell vehicles?

The favored anode catalyst in a hydrogen fuel cell is platinum(1) or another platinum-group element (e.g. palladium). The catalyst is required in small quantities for an individual fuel cell but of ...
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3 votes
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Less energy consumption when we stop using fossil fuels?

tl;dr replacing fossil fuels with clean, sustainable alternatives would save ~17-20% of current total global energy consumption. I'll start by noting that energy efficiency is just a side perk of ...
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3 votes

Fuel efficiency when decelerating on a hill

Generally a driver doesn't know the exact angle of the hill at any point in time, nor do they generally know the exact combination of gear and gas-pedal that will be the most efficient. Maybe some ...
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3 votes

Why are electrical cars encouraged but is electrical heating discouraged?

There are a couple of good answered already, but here's another perspective (who said a question can only have one right answer!). In a possible future world where electricity generation is ...
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3 votes

Why are electrical cars encouraged but is electrical heating discouraged?

The biggest reason is why it is being used. Converting combustion heat into electricity and then converting electricity back into heat is highly inefficient. Better to just create the heat by ...
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  • 187
3 votes

Why are electrical cars encouraged but is electrical heating discouraged?

The first part of your question is about where pollution happens as much as about pollution reduction. Cars emit pollution where people are, while electric generators can be built further away from ...
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  • 3,755
3 votes

Can alloy wheels (for a car) pay for themselves through fuel savings?

Theory The calculation in the other answer is rather naive. I haven't done the calculation myself, but there are a few things to consider. First of all, lighter wheels mean more than just lower ...
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  • 131
3 votes

What measures could be taken to decrease the air pollution in a big city?

This brochure of the European Environmental Bureau gives 12 good tips to reduce air pollution in a city. Here a summary and some extra information I added: Create Low Emission Zones (LEZ): charge or ...
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  • 179
3 votes

How to prevent older Diesel cars from emitting NOx, dust and smell?

By crushing the car and recycling the metal. That's how. Diesel cars are awful and there's pretty much nothing anyone can do about it, if the recent VW diesel cheating scandal hasn't already made ...
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  • 426
3 votes

The more miles a car drives, the more economical battery packs become?

The article is considering the total costs of ownership of electric vs internal combustion engined (ICE) cars, including purchase and running costs. One of the benefits of electric cars is that fuel ...
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