Electric car + solar panels

Ditzy_Mitzy

AdrianC said:

Belenus said:

Should the bonnet, roof and tailgate of electric cars be made out of solar panels?

It's been tried.
https://blog.toyota.co.uk/introducing-new-prius-plug-in

They aren't nearly big enough, even before you get to any other issues.
https://www.inverse.com/article/34253-elon-musk-tesla-cars-solar-roof

Doesn't stop people throwing it about in their latest hare-brained crowdfunder, though...
https://sonomotors.com/

That Sono thing looks ridiculous.  I've got a solar array on my house, so know that direct sunlight is needed in order for power to be generated.  That car, especially in an urban area, is unlikely to be directly beneath the sun for anything like as long as will be needed for an array of that size to materially charge its batteries.  Not only will it have to cope with the usual solar issues of cloud cover, rain, fog and other adverse weather; it will also have to deal with the fact that it's much shorter than the average building.  Parking it anywhere in the shadow of a building, tree, bridge or other structure will render the solar panels useless.  Not to mention it won't work in covered car parks, garages and so on.  Even open car parks will present an issue: if another car parks next to the Sono, it will block the path between the sun and the panels on the side.  This will reduce the size of the working array.  If another car parks on the other side, the array size reduces further.  There's also the issue that cars get dirty.  The Sono would need to be washed almost daily to ensure effective functioning of the panels.  Even a fraction of an inch of road dirt, mud and dust will block the light.  

ElefantEd

I seem to remember that Nissan Leaf's had an optional solar panel accessory, but it was only used to trickle charge the 12V battery. As such it was a complete waste of time and money.

What makes more sense (in sunnier countries, anyway) is for charging stations to have solar panels (and an electric storage system) so that cars are parked underneath the shade and use the juice for charging.

Bluebell1000

Aptera is getting closer with 10 miles per kWh and solar panels, but (I think) it's ugly, and I would not feel comfortable on a motorway with it being so tiny! https://www.caranddriver.com/news/a34875659/aptera-ev-solar-no-charging-revealed/ 

AdrianC

You want massive efficiency? That's the ONLY way to do it. Very low drag, absolute bare minimum fripperies to keep weight and frontal area to a minimum.

But... That piece says it weighes a ton... Literally. 2200lb = 1000kg. That's the same weight as a brand new normal ICE Corsa. It's 50% heavier than a properly lightweight conventional car like a Citroen AX.

It's good to see distance/kWh getting a bit of focus for a change, though. That's efficiency on a par with miles per gallon. Quoting range is simply like saying how big the fuel tank is in a normal ICE car... It's only relevant if there's an actual problem that restricts use. For BEVs to become mainstream, range anxiety needs to actually be put to bed - and simply quoting range is tacitly admitting it hasn't been.

The fuel tank on my current sensible daily is tiny - 30 litres. 300 mile range. But, of course, replenishing that range takes a couple of minutes without any great hassle. And, yes, in local use, it's trivial. It's filling up every couple of weeks instead of every three - and, yes, for a local-use BEV with adequate charging access, it's similarly trivial-to-irrelevant.

But as soon as you get outside of that local-use only pattern... It's not being able to do that round-journey without a break to replenish. And if that break extends past a handful of minutes, it becomes a positive imposition. And if that break requires a non-trivial diversion or active route planning...

DrEskimo

AdrianC said:

You want massive efficiency? That's the ONLY way to do it. Very low drag, absolute bare minimum fripperies to keep weight and frontal area to a minimum.

But... That piece says it weighes a ton... Literally. 2200lb = 1000kg. That's the same weight as a brand new normal ICE Corsa. It's 50% heavier than a properly lightweight conventional car like a Citroen AX.

It's good to see distance/kWh getting a bit of focus for a change, though. That's efficiency on a par with miles per gallon. Quoting range is simply like saying how big the fuel tank is in a normal ICE car... It's only relevant if there's an actual problem that restricts use. For BEVs to become mainstream, range anxiety needs to actually be put to bed - and simply quoting range is tacitly admitting it hasn't been.

The fuel tank on my current sensible daily is tiny - 30 litres. 300 mile range. But, of course, replenishing that range takes a couple of minutes without any great hassle. And, yes, in local use, it's trivial. It's filling up every couple of weeks instead of every three - and, yes, for a local-use BEV with adequate charging access, it's similarly trivial-to-irrelevant.

But as soon as you get outside of that local-use only pattern... It's not being able to do that round-journey without a break to replenish. And if that break extends past a handful of minutes, it becomes a positive imposition. And if that break requires a non-trivial diversion or active route planning...

Definitely.

That's why it's important to look at both efficiency and charging speed in the context of long range.

On paper a 22kWh Hyundai seems like it suits 'city car' status, but it's high efficient of ~5mi/kWh nearly all year round, plus the fact it can consistently charge at a rate of about 70kW right up to 80% SoC means it can do long journeys really well. Relative to something like a e-208, it will be able to complete a 1000km journey in about the same time, despite the e-208's 50kWh battery and peak charging speed of 100kW.

This is why the Tesla Model 3 is so hard to beat. Great efficiency, great battery capacity, amazing charging speeds AND a relatively numerous and reliable charging network to boot.

Ectophile

This is why the Tesla Model 3 is so hard to beat. Great efficiency, great battery capacity, amazing charging speeds AND a relatively numerous and reliable charging network to boot.

An expensive car usually beats a cheap city car if you don't consider the affordability.

DrEskimo

Ectophile said:

This is why the Tesla Model 3 is so hard to beat. Great efficiency, great battery capacity, amazing charging speeds AND a relatively numerous and reliable charging network to boot.

An expensive car usually beats a cheap city car if you don't consider the affordability.

Except the Hyundai 22kWh is less than half the cost of the e-208.

Also the Jaguar i-Pace, Audi E-Tron, Mercedes EQC and Polestar 2 are more expensive and none of them come close.....

AdrianC

Sorry, which electric Hyundai can you order brand-new for under £15k?

Peugeot e-208 new list price starts at £29,725.
https://offers.peugeot.co.uk/choose-your-peugeot/configure-all-new-208

Hyundai Kona electric list price starts at £30,100
Hyundai Ioniq electric list price starts at £30,950
Hyundai i10 petrol starts at £12,820
https://www.hyundai.co.uk/new-cars

DrEskimo

AdrianC said:

Sorry, which electric Hyundai can you order brand-new for under £15k?

Peugeot e-208 new list price starts at £29,725.
https://offers.peugeot.co.uk/choose-your-peugeot/configure-all-new-208

Hyundai Kona electric list price starts at £30,100
Hyundai Ioniq electric list price starts at £30,950
Hyundai i10 petrol starts at £12,820
https://www.hyundai.co.uk/new-cars

You can't now. It was the old Hyundai Ioniq.

It's been superceded by the 38kWh model that charges at a much slower rate.