Fuel consumption as an area

[exchemist]

4 hours ago, Arthur Smith said:

Z

There is indeed a typo in my comment. I meant "cubic millimetres" where I wrote "cubic millilitres". I believe the arithmetic is correct, though.

And to clarify, I think representing fuel consumption as an area is trivial and unhelpful.

I'd be much more interested in how to compare holding on to a reasonably economic, well maintained IC car or swapping for an all-electric, taking into account all the relevant factors, including the overall carbon footprint.

 

Eta including the carbon cost of manufacturing an electric car and its batteries.

From what I have read, it is better to keep an old IC vehicle as long as you can, before trading it in for an EV, due to the large and unavoidable carbon footprint of manufacturing a new vehicle, of any type. But your next purchase, whenever it is necessary, should be an EV. The longer you can leave it , the greener the EV will be , since the renewable proportion of the electricity it consumes will grow as the years pass. Also the charging network will get better over time. I'm currently running a 19yr old petrol VW Golf, (the 1.4l one with both supercharger and turbocharger, which performs like a 2l but with much better fuel economy). It still works fine and does what I need it to do, so I intend to hang onto it for another year at least. 

Edited October 5, 2023 by exchemist

[Arthur Smith]

1 hour ago, exchemist said:

From what I have read, it is better to keep an old IC vehicle as long as you can, before trading it in for an EV, due to the large and unavoidable carbon footprint of manufacturing a new vehicle, of any type. But your next purchase, whenever it is necessary, should be an EV. The longer you can leave it , the greener the EV will be , since the renewable proportion of the electricity it consumes will grow as the years pass. Also the charging network will get better over time. I'm currently running a 19yr old petrol VW Golf, (the 1.4l one with both supercharger and turbocharger, which performs like a 2l but with much better fuel economy). It still works fine and does what I need it to do, so I intend to hang onto it for another year at least. 

My runabout is a twenty-two-year-old golf 1.6 (naturally aspirated) and I have the same plan: hang on to it until something major breaks while watching developments in electric cars. There is currently also a scheme to subsidize photovoltaic installation, with the ability to sell excess back to the grid. My neighbour already has a roof installation that delivers 9KVA in good daylight. The idea of charging my car with free electricity appeals very much.

[exchemist]

16 minutes ago, Arthur Smith said:

My runabout is a twenty-two-year-old golf 1.6 (naturally aspirated) and I have the same plan: hang on to it until something major breaks while watching developments in electric cars. There is currently also a scheme to subsidize photovoltaic installation, with the ability to sell excess back to the grid. My neighbour already has a roof installation that delivers 9KVA in good daylight. The idea of charging my car with free electricity appeals very much.

That may be a good strategy, as one of the issues not much discussed as yet is the need to rewire entire neighbourhoods to cope with the higher electricity demand, once most people have EVs. If people can generate at least a proportion themselves it could help a lot. 

[Genady]

Almost all my trips are quite short, 2-5 miles each. I guess, battery recharge time would not be an issue in this case. How else would EV and IC cars compare in such use?

Edited October 5, 2023 by Genady

[StringJunky]

26 minutes ago, Genady said:

Almost all my trips are quite short, 2-5 miles each. I guess, battery recharge time would not be an issue in this case. How else would EV and IC cars compare in such use?

At those distances, you'll always be running the car at sub-optimal temps most of the time, I would have thought, which means the the air/fuel ratio will be rich most of the time.

Edited October 5, 2023 by StringJunky

[Genady]

4 minutes ago, StringJunky said:

At those distances, you'll always be running the car at sub-optimal temps most of the time, I would have thought, which means the the air/fuel ratio will be rich most of the time.

Does it matter that our air temp is around 27-32⁰C year around?

[StringJunky]

20 minutes ago, Genady said:

Does it matter that our air temp is around 27-32⁰C year around?

I don't know, but relatively. The operating and maintenance temperature of the cylinder wall is 180c about. Even at 27-32c atmosphere you still have to raise the temp of the engine block 150c.

Edited October 5, 2023 by StringJunky

[studiot]

1 hour ago, Arthur Smith said:

My runabout is a twenty-two-year-old golf 1.6 (naturally aspirated) and I have the same plan: hang on to it until something major breaks while watching developments in electric cars. There is currently also a scheme to subsidize photovoltaic installation, with the ability to sell excess back to the grid. My neighbour already has a roof installation that delivers 9KVA in good daylight. The idea of charging my car with free electricity appeals very much.

Did you miss my last post ?

 

The Uk electricity supply is 230 volts at 13 amps single phase from a single domestic socket. That gives you 3kVA.

More power can be had by using a dedicated 30 amp supply, still at 230 volts. That is equivalent to one ring main direct wiring from a single fuseway in the box. This is nearly 7.5 kVA and is used for say 8 kVA instantaneous showers.

However the charging lead for my brother's car, like most uk electric vehicles limit the input current to 10 amps at 230 volts.

 

So your neighbour has 9 kVA in good daylight. Jolly good if he is a night worker and charges hois car in the day otherwise he would have to layout for storage capacity equal to a day's charge, if he wanted to work in the day and sleep at night. say anothe £15000 on top of the panels and vehicle.

 

1 hour ago, Genady said:

Almost all my trips are quite short, 2-5 miles each. I guess, battery recharge time would not be an issue in this case. How else would EV and IC cars compare in such use?

In which case the EV would be more efficient, if you returned to base between trips.

My other brother is on his second hybrid with a 25 - 30 mile range and does mostly short local trips like you do.

Mainly the batery allows the vehicle to half its fuel consumption or double the miles per litre.

This is again competitive with all electric.

 

22 minutes ago, Genady said:

Does it matter that our air temp is around 27-32⁰C year around?

Some thread back I published an efficiency graph for an EV battery, here at SF.

Their optimum temperature is 23^oC, although the fall off is much less severe at higher temperatures it is still less efficinet at 30 than 23.

[Genady]

15 minutes ago, StringJunky said:

The operating temperature of the cylinder wall is 180c about. Even at 27-32c atmosphere you still have to raise the temp of the engine casing 150c.

Thank you. This goes towards EV.

 

14 minutes ago, studiot said:

In which case the EV would be more efficient, if you returned to base between trips.

I do, so this goes towards EV.

 

15 minutes ago, studiot said:

Their optimum temperature is 23^oC, although the fall off is much less severe at higher temperatures it is still less efficinet at 30 than 23.

This needs to be considered. Thank you.

[studiot]

17 minutes ago, Genady said:

This needs to be considered. Thank you.

Sure.

But beware og these EVs

https://www.bbc.co.uk/news/uk-scotland-67005620

 

 

[Arthur Smith]

9 hours ago, exchemist said:

 If people can generate at least a proportion themselves it could help a lot. 

My house is 42° N, with (maybe too) many sunny days. Plus the grant, zero interest loan and buyback scheme means there is no downside. Unless the plug gets pulled on the buyback scheme.

8 hours ago, studiot said:

Did you miss my last post ?

 

No.

8 hours ago, studiot said:

More power can be had by using a dedicated 30 amp supply, still at 230 volts. That is equivalent to one ring main direct wiring from a single fuseway in the box. This is nearly 7.5 kVA and is used for say 8 kVA instantaneous showers.

However the charging lead for my brother's car, like most uk electric vehicles limit the input current to 10 amps at 230 volts.

Ring mains! I'd forgotten about those. In France domestic sockets are fused at 16A (no ring mains) but single spurs can be 20A. When I lived in UK, the main fuse was rated at 100A. Here, my contract limits me to 9KVA, exceeding that for any length of time causes the system to trip. Just checking my app, I see my average consumption so far today is less than 1KVA. I haven't checked but I've heard one can installa 70KVA home charging point.

8 hours ago, studiot said:

So your neighbour has 9 kVA in good daylight. Jolly good if he is a night worker and charges hois car in the day otherwise he would have to layout for storage capacity equal to a day's charge, if he wanted to work in the day and sleep at night. say anothe £15000 on top of the panels and vehicle.

There's a buyback scheme. Excess electricity is money in his pocket and avoids having a battery storage system.

OK, so charging cables and home charging points are a bit of a minefield. EVs have a maximum charge rate (single phase) that maxes at 7KW for top of the range. A 32A point also gives 7KW. Charging cables vary in carrying capacity, with type 1 capable of handling up to 7KW.