Electric vehicles

[TominDales]

Energy density per litre and per kilo is the main problem. 900Wh/litre seems to be the current pinnacle of battery technology. Unfortunately they measure fossil fuel energy in different units, but it seems that batteries currently offer about 1% of the energy density of fossil fuels, and this may increase to 10%, when we reach the pinnacle of battery technology.

The good news is that electric motors are more efficient, so it's not quite as awful as the numbers suggest. It's still pretty dreadful though. A nice article on why jumbo jets can't ever be fueled by batteries: Flying Without Fossil Fuels: The Need For High Energy Density

About three years ago there were a few announcements about using atmospheric carbon dioxide to make liquid fuels - I haven't heard anything since, but that might be a better use of our time than chasing what seems to be a bit of a unicorn.

A quick search gave me a Forbes article, which says using the current technology the cost is about $4/gallon, which is not too far away from conventional fuel. Certainly not orders of magnitude higher. Carbon Engineering - Taking CO2 Right Out Of The Air To Make Gasoline

The key point with engineering solutions is its horses for courses. So a mix of EV, hydrogen, SAF, etc will be the solution.

At the moment battery technology seems the most cost effective and convenient solution for vehicles. Its beggining to look like its will also be a solution for trucks and HGVs but the R&D and innovation is still at an early stage to be sure. Fuel cells seem to be on the waine for HGVs in favour of EVs. recent announcement by Scania to that effect.

For airlines, SAF is the proffered opti on SAF - Sustainable Aviation Fuels. The name has been chosen carefully as many supposedly sustainable solutions have bad side effects. So for instance growing maze (US Corn) to produce ethanol as a bio fuels uses water, fertilizer and other resourses and may effect global food supply. whereas the reference you make taking CO2 from the air is sustainable. US airlines have recently announce this is there preferred option. Major U.S. Airlines Commit to Net-Zero Carbon Emissions by 2050 | Airlines For America,
as you point out, SAF has good energy density and is a drop in replacement needing very little change to the aircrafts engineering.

There are programmers looking at turning CO2 into fuels, most are taking waste CO2 from industrial processes such as steel making, petrochemical refining etc as this have high concentration of CO2 and so the pumping costs (pressurisation of the CO2) are relatively low and more affordable. The example you gave of CO2 from air is very energy inefficient as the air only has 400ppm of CO2, so is likely to be way down the list of viable projects. A way of making negative carbon is to take CO2 emitted from fermentation such as brewing or the big bioethanol plants that make pure CO2 which has been derived from the atmosphere - it mostly goes into make fizzy drinks. Nottingham university has found a bug that can eat Hydrogen and use it to turn CO2 into ethanol. Once you have ethanol you can use conventional chemistry to make SAF.

Having said all that, Boeing, Airbus and Rolls are looking at all electric planes for short hall hops of say 100 miles for light planes. As you point out a plane needs a lot of power, an Airbus A320 needs 20mW to take off, so its unlikely that will come from EV in the short term. However SAFs and jet engines cause noise pollution and NOX, so another option is to see if the plane can take off with electric ie lots of fans and once in the sky the jets open up to take people on long-hall.
Its horses for courses with many combined technologies

 

[TominDales]

I haven't needed to change a bulb on any of the vehicles in at least 25 years though I dread to think of the cost involved if my car headlights develop a fault. LED matrix intelligent light system, sounds like mega bucks.

Um as its fairly new tech, you may be unlucky. LEDs being semiconductors will pretty well last forever - ca 20k to 30,000 hrs and some. The problem is the ballasts - power supply and the electronic controls. That's why most home LEDs fail. Auto companies plan on a design life of about 10 years for cars, so likley to have high quality ballast designed to take the power and heat for 10 to 15 years of use (bearing in mind vehicles don't get a lot of use). Not so sure about motorhomes, campervans etc which should have a longer planned service lifetime, but I suspect they are built on modified car designs. Probably one to take on the chin.

 

[Rorschach]

Um as its fairly new tech, you may be unlucky. LEDs being semiconductors will pretty well last forever - ca 20k to 30,000 hrs and some. The problem is the ballasts - power supply and the electronic controls. That's why most home LEDs fail. Auto companies plan on a design life of about 10 years for cars, so likley to have high quality ballast designed to take the power and heat for 10 to 15 years of use (bearing in mind vehicles don't get a lot of use). Not so sure about motorhomes, campervans etc which should have a longer planned service lifetime, but I suspect they are built on modified car designs. Probably one to take on the chin.

It is probably design more than anything that causes failures. LED's are very sensitive to heat. In an effort to keep costs down and give maximum light output companies overdrive the LED or at least run it it right on the limit of what it can handle. This causes a lot of heat and heat damages the LED or the electronics around it, causing premature failure.

BigClive did an excellent video recently on Dubai(?) LED bulbs which have a much better design and should last far longer than a generic bulb and use less energy too, but they are much more costly to manufacture of course and produce less light.

 

[D_W]

It is probably design more than anything that causes failures. LED's are very sensitive to heat. In an effort to keep costs down and give maximum light output companies overdrive the LED or at least run it it right on the limit of what it can handle. This causes a lot of heat and heat damages the LED or the electronics around it, causing premature failure.

BigClive did an excellent video recently on Dubai(?) LED bulbs which have a much better design and should last far longer than a generic bulb and use less energy too, but they are much more costly to manufacture of course and produce less light.

I've noticed the same about LEDs in general - the early LEDs are cool running. I have a green flashlight from around 1996 or so. It'll be working in 2036. The light output isn't high and it's from a period prior to when white LEDs were widely available, but it does its thing without drama. I vaguely recall that it was about $27 back then (which was a princely sum for a small flashlight that only makes a bit of light) and blue was 10% more. Red was also available (But the buddy who had these early on was a pilot looking for a light he could use often and a lot of the lines are red, so red LED was a no-no. Thus, we have green.

It's still the flashlight that I use when I rifle through a few high output lights when the power goes out only to find that something no longer works on them. Old greenie always lights up and goes somewhere between 100 and 200 hours on a pair of batteries.

 

[Spectric]

was putting a set of points in a neighbours Morris Minor a few days ago. (For those under the age of 60 a set of points are contacts driven by a cam from the distributor to provide properly timed pulses of 12-volt electricity to the ignition coil.

Almost there, the basic principle of producing a Hv spark from an autotransformer(coil) is known as the kettering principle, the spark is produced when the points open and the magnetic field in the coil collapses, the capacitor is used to ensure the current flow is interupted abruptly without arcing across the points as they open. Easy when you have worked on the design of automotive ignition systems and CDI systems for two stroke motorcycles and yes I am near sixty.

 

[TominDales]

It is probably design more than anything that causes failures. LED's are very sensitive to heat. In an effort to keep costs down and give maximum light output companies overdrive the LED or at least run it it right on the limit of what it can handle. This causes a lot of heat and heat damages the LED or the electronics around it, causing premature failure.

BigClive did an excellent video recently on Dubai(?) LED bulbs which have a much better design and should last far longer than a generic bulb and use less energy too, but they are much more costly to manufacture of course and produce less light.

Yes that's the issue with household and budget lighting, made on a budget and relatively poor heat management. Although the main brands seem to last quite well there is a lot of cheap chinses supply these days. Its still usually the ballast that fails - at least that's what the Thorn (Zumtoble) lighting guys in Spennymoore tells us. Bright LED lights are really quite specialist for automotive use so i'd expect them to have really good ballast and heat management, but its relatively new technology so there will be some dud products.

 

[Lons]

Um as its fairly new tech, you may be unlucky. LEDs being semiconductors will pretty well last forever - ca 20k to 30,000 hrs and some. The problem is the ballasts - power supply and the electronic controls. That's why most home LEDs fail. Auto companies plan on a design life of about 10 years for cars, so likley to have high quality ballast designed to take the power and heat for 10 to 15 years of use (bearing in mind vehicles don't get a lot of use). Not so sure about motorhomes, campervans etc which should have a longer planned service lifetime, but I suspect they are built on modified car designs. Probably one to take on the chin.

I won't have the car that long, it's 3 1/2 years old with 19k on the clock now which is the longest I've had a car for a while and I'd have changed it by now but have to pay for my wife's foot operation soon, just as well I changed hers in September or she would be waiting for her new Mini instead. The motorhome isn't an issue neither is the other little Skoda.

 

[TominDales]

Almost there, the basic principle of producing a Hv spark from an autotransformer(coil) is known as the kettering principle, the spark is produced when the points open and the magnetic field in the coil collapses, the capacitor is used to ensure the current flow is interupted abruptly without arcing across the points as they open. Easy when you have worked on the design of automotive ignition systems and CDI systems for two stroke motorcycles and yes I am near sixty.

The Charles Kettering ignition system was a wonder of its day in 1911 and won the UKs prestigious Dewar Trophy for allowing cars to not need to be cranked

 

[Spectric]

Can you imagine when you actually had a flame as the source of ignition, hard to imagine having to light your car and now we are dreaming of all transport becoming electric.

 

[D_W]

Can you imagine when you actually had a flame as the source of ignition, hard to imagine having to light your car and now we are dreaming of all transport becoming electric.

How about steam cars having to build steam (they didn't keep too big of a boiler, but relied on high heat output, but it still wouldn't have been 15 seconds), and then the instructions when you had a fire on a steam car not to stop (the car will burn to the ground), but rather cut fuel and speed up on remaining steam to blow the fire out.

 

[Terry - Somerset]

I'm not sure if steam cars had the same "safety" systems as some steam trains - in the event of overheating or a failure of the pressure relief valve, you could dump the contents of the firebox on the track.

Somewhat less damaging than an explosion.

 

[Spectric]

I love the smell and sound of a good old steam train, reminds me of the fact that great britain was once upon a time really great.

 

[Woodmatt]

I love the smell and sound of a good old steam train, reminds me of the fact that great britain was once upon a time really great.

Great Britian was great,you must have a long memory

 

[Spectric]

No it just reminds me of the history I have learnt over the years, we have certainly been going down the pan during Elizabeths reign, I wonder if Victoria ever pays her a ghostly visit to rub it in.

 

[chrisdt]

Probably not good to think about the past too much but I was watching the "Smart Motorway" Highways England "Education ad on TV and I wondered how that rather portly gentleman managed to remove himself from the passenger door, let alone jump over the barrier. I went to one of the last vintage car rallies before lock down. My 1936 Jowett was of the road so I went in a friends 57 Ford Zodiac. What a lovely car to drive. No big plastic lump in the middle with numerous lights telling you what the weathers like in Mombasa or the Air conditioning needs attention and other useless information. Just a lovely long bench seat positive column change and basic instrument panel. Easy to change light bulbs. Easy to check oil level with a dipstick (note BMW and others) A cam chain that lasted the life of the car albeit a bit noisy and errrm so easy and and quick to slip out of the passenger door before a 40 ton Freightliner sent you to the promised land. That ad on TV seems to refer only to a breakdown. What if.......A lone driver feels really really poorly. He just might be able to pull on to a hard shoulder but not drive to an emergency bay which could be up to a mile away (HE have admitted lying about the distance apart)

 

[Spectric]

Easy to change light bulbs. Easy to check oil level with a dipstick

What you want a vehicle that you can change bulbs without taking the light unit out, what next do you realise you could be doing your local garage out of a job!
Just think yourself lucky that they do not have to plug the vehicle into a computer to be told what bulb needs changing.

I can remember being told by a bean counter, ok a senior bean counter that as an engineer we must design for manufacturing and not for repair or maintainance that should only occur out of warranty anyway.

 

[Geoff_S]

Probably not good to think about the past too much but I was watching the "Smart Motorway" Highways England "Education ad on TV and I wondered how that rather portly gentleman managed to remove himself from the passenger door, let alone jump over the barrier. I went to one of the last vintage car rallies before lock down. My 1936 Jowett was of the road so I went in a friends 57 Ford Zodiac. What a lovely car to drive. No big plastic lump in the middle with numerous lights telling you what the weathers like in Mombasa or the Air conditioning needs attention and other useless information. Just a lovely long bench seat positive column change and basic instrument panel. Easy to change light bulbs. Easy to check oil level with a dipstick (note BMW and others) A cam chain that lasted the life of the car albeit a bit noisy and errrm so easy and and quick to slip out of the passenger door before a 40 ton Freightliner sent you to the promised land. That ad on TV seems to refer only to a breakdown. What if.......A lone driver feels really really poorly. He just might be able to pull on to a hard shoulder but not drive to an emergency bay which could be up to a mile away (HE have admitted lying about the distance apart)

A few years again my wife and I went to Malmsebury for a "history weekend". Not being very interested in the Tudors and stuff (my wife is and I've been beaten to death with it), I took a trip out to a local car museum. And it was really, really interesting seeing a really nice collection of old museum cars ..........

...... until I realised how many of them I had owned and had known. I had officially become a museum piece.

 

[Jameshow]

Probably not good to think about the past too much but I was watching the "Smart Motorway" Highways England "Education ad on TV and I wondered how that rather portly gentleman managed to remove himself from the passenger door, let alone jump over the barrier. I went to one of the last vintage car rallies before lock down. My 1936 Jowett was of the road so I went in a friends 57 Ford Zodiac. What a lovely car to drive. No big plastic lump in the middle with numerous lights telling you what the weathers like in Mombasa or the Air conditioning needs attention and other useless information. Just a lovely long bench seat positive column change and basic instrument panel. Easy to change light bulbs. Easy to check oil level with a dipstick (note BMW and others) A cam chain that lasted the life of the car albeit a bit noisy and errrm so easy and and quick to slip out of the passenger door before a 40 ton Freightliner sent you to the promised land. That ad on TV seems to refer only to a breakdown. What if.......A lone driver feels really really poorly. He just might be able to pull on to a hard shoulder but not drive to an emergency bay which could be up to a mile away (HE have admitted lying about the distance apart)

That's progress for you!

I really think we should have had greater say over such an important matter.

Cheers James

 

[Amateur]

In not buying one till the batteries are smaller and I can clip them in my Makita 18v charger every night.

 

[Droogs]

For those interested in some amazing engineering, here is the worlds first PHEV