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23

Electric motors generally: are easier to maintain are very efficient (80-90% compared to 20-30% for ICEs) have a very wide range of operating speed, so need no gears, or fewer gears, to move through their full speed range make it easy to incorporate regenerative braking. can provide full torque from stationary Consequently, heavy-duty applications such as ...


16

I agree with everything in EnergyNumbers' answer, but would like to add some more: (Other) Advantages of Electric Motors Along the lines of "easier to maintain", an electric motor is likely to last much longer, for example, in an automotive application, than an internal combustion engine (ICE). An EV traction motor may very well last 1,000,000 miles, ...


9

From the general principles outlined in Sustainable Energy--without the hot air by David J.C. MacKay (http://www.withouthotair.com/c20/page_118.shtml): In short-distance travel with lots of starting and stopping, the energy mainly goes into speeding up the vehicle and its contents. Key strategies for consuming less in this sort of transportation are ...


9

Ok (1.5 hours later). Going by this reference for bag GWP and EPA values for burning petrol, I've got 1.57 kg CO2-eq per plastic bag, 271 kg CO2-eq for cloth bags, and 2.35 kg CO2-eq per L of petrol. Putting those together with variables for how much gas is saved by delivery and how many total trips you want to consider, here's the data I come up with: ...


7

There are, obviously, two options here: recycling, and reusing (basically anything else you had mentioned in the question). Recycling For recycling one can look for recyclers who would pick up the vehicle, and pay for it. Big truck like F-350 could fetch up to $1000 depending on the market, because it has a lot of iron in it. Those recyclers usually would ...


6

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 was what to do about horse manure. Rutgers University has a fact sheet about horses and manure. It states that a 1000 lb horse will produce about 9.1 tons of ...


6

Looking through some of your sources and thinking about the problem, it sounds like there isn't necessarily a definite answer, but a set of tradeoffs. NOx is associated with smog and acidification, particulates are related to respiratory health, and fuel efficiency is related to global warming (among other things like cost). This problem would seem to be ...


5

You can use scrubbers to remove NO2 (or better NOX) and SO2 from exhaust gas emissions. Scrubbers are used in large industrial facilities, power plants, and large ships to clean-up the exhaust gas emissions -- mainly in order to comply with emission thresholds. They are not applied in small-scale combustion facilities such as cars or residential heating ...


5

Three routes: A: Your van has all your worldly possessions. B: In addition you have a place you can store stuff. C: Use a car towable R.V. A: Everything is in your van. Consider removing the back doors and buiding a box that fits into this space. The back panel folds down to make a table. A propane tank and a gas stove is how you cook. Or you have ...


5

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 most efficient way to commute it is to use public transport, for which the weight-of-vehicle to weight-of-passenger ratio is lowest. For trains, the amount of ...


4

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 that drive more than 20,000 miles a year. If there is a benefit to electric vehicles per mile driven, that benefit will be realized more quickly by someone who'...


3

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 costs are very low; the car costs more to buy, but costs less to run. The point at which owning an electric vehicle becomes more economical than an ICE one ...


3

This site links to a number of enclosed human powered vehicles but the only one that is available for me to purchase locally is the ELF. What could be more fun than riding your ELF? Riding with friends on board, of course! The ELF 2FR allows multiple passengers to ride along with you, seated on a comfortable padded seat behind the driver’s seat. A ...


3

There are recumbent bicycles that shield you from rain and wind, for example: Image by Gandalf24 at da.wikipedia - Own work, Public Domain The shielding is called fairing. According to this Wikipedia article: Fairings are also available for upright bikes, but are much less common I'm not sure if they refer to a fairing that completely shields the biker ...


3

exploring the problem I've asked around on the Claverton Energy Group for some help on this. Thanks to John Baldwin, I learnt that biogas tends to be about 65% methane, with a lot of carbon dioxide, and some oxygen and hydrogen sulphide. Whereas gas as supplied for industrial, commercial and residential use is 90%+ methane, plus gases such as propane and ...


3

The only option that I can see which would be win-win would be to take public transport to the supermarket and use my reusable bags. Hardly. I present, the bike trailer: For five years, I actually had a trailer specifically for hauling my two kids around in (the Cheetah Chariot 2 kid version, now owned by Thule), but it would do double-duty as a stroller ...


3

I have two words for you, "Project Car". Seriously, though, donate it to the auto-tech department of your county career center or community college. The students get experience by fixing it up, then proceeds from the sale fund operation of the auto-tech department.


2

I don't have the perfect answer but as you said, even though it's not really fuel-efficient, it might be more ecological than creating a brand new car. Especially if we consider that it could be used occasionally by someone who wouldn't need to drive a lot, this could always help that person. (Maybe it could be recycled, could it be?) EDIT: Remember than ...


2

Fuel consumption is typically 70-90% of a vehicle's lifecycle energy consumption and greenhouse gas (GHG) emissions, so there are lots of circumstances where upgrading to a significantly more energy-efficient vehicle makes a lot of sense. See, for details TRL VR6 and The UK Automotive Sector: Toward Sustainability. If the vehicle being replaced gets a very ...


2

An electric scooter would be ideal. Bicycles suffer from a peculiar characteristic of humans, namely that they produce power at a ridiculously low RPM. Power is force times speed. If speed is low, to get any useful power, you need huge amounts of force. The rotational equivalent is that power is torque times RPM, very similar to the linear equation. Let's ...


2

Given the high price of the enclosed pedal powered vehicles described above, it seems that the better option is to get an e-bike (so you can ride in heavy clothing without sweating too much and carry all the gear with you), and fit panniers so that you can carry your wet weather gear at all times. You could afford to really go to town on clothing and still ...


2

A self-contained solar-powered car is not viable. There simply isn't enough area for the solar panels. Take a Honda Civic as an example: it's got about eight square meters of top surface that solar panels could be installed on, for a peak theoretical generation of 8 kW. That same Honda Civic has a 92-kW engine, meaning that for each second of maximum ...


1

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 course this demand scales up linearly with the number of fuel cells you want to produce. There is ongoing research into development of alternative anode ...


1

In general, any two or three wheeler with a one-speed transmission and no manual clutch, or with a two-speed automatic transmission, and a ~50cc engine, is a moped. Some states don't require tag and insurance but most states require a driver's license. Also, the top speed of the moped is likely required to be 30 MPH. Note that only "most states" require a ...


1

Just found a patent for this: https://www.google.com/patents/US20070154374 Method for removing sulfur dioxide and other acid gases, mercury, and nitrogen oxides from a gas stream with the optional production of ammonia based fertilizers


1

Emissions per passenger kilometre will be high in your van, unless you carry more people! Consider picking up hitchhikers or doing ride sharing :)


1

Specific to electric vehicles in the USA, the Union of Concerned Scientists created a good comparison in 2009. Here's the latest update, from 2018-03-08: https://blog.ucsusa.org/dave-reichmuth/new-data-show-electric-vehicles-continue-to-get-cleaner Based on data on power plant emissions released in February 2018, driving on electricity is cleaner than ...


1

I think you had pretty much of advice pro electrical. I do not preach combustion is better than electrical, but would like to make some side notes in favor of combustion. Energy efficiency: The energy for your electrical engine must come from somewhere. These sources are probably combustion engines, so basically you are adding an extra conversion which ...


1

I have driven a hybrid since 2000 and noted that I get 39.6 miles per gallon. This is primarily due to the fact that I do mostly freeway driving. I do get much better gas mileage when using city streets. This is because at lower speeds the hybrids will use the battery for power in place of gas. So when looking at a car you may want to take into account your ...


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