Solar PV on electric cars

[Neilm]

Governments earn big bucks from tax on fuel. Do you really think they will let that milk cow go away (*)?

Just tax sunlight.

Adding solar panels also means adding the electronics to step up the output voltage so it can charge the traction battery. That will introduce quite a lot of losses. The best idea I have heard of is car mounted solar panels charging the 12 V battery but it all does sound like solar roadways in a new guise.

[bdunham7]

Is putting solar panels on an EV a good idea?

Already done: https://sonomotors.com/de/sion/
Toyota, Kia and Hyundai use solar panels for the next generation of BEV and PHEV.
https://www.electrive.com/2019/07/04/toyota-testing-hybrid-prius-fitted-with-solar-cells/

wraper mentioned stupid, are Toyota, Kia and Hyundai stupid or just ahead of the rest of the stupid other EV manufacturers ?

I think "not practical" would be a more diplomatic term than "stupid", but wraper doesn't mince words.  The Prius mentioned uses very expensive multi-junction cells (34% efficiency is still pretty expensive) and is a concept test car.  It isn't an economically viable solution yet.  The Sion, AFAIK, is vaporware and I haven't seen a justification for their remarkable claim of 34km/day (in Deutschland no less), so we'll wait and see. 

Meanwhile, my 30 panels on the roof have each been producing that 1.2kWh/day for the past 7 years at a cost that is probably less than 10% of what the equivalent solar panel system on a car would be.  Unless I were desperately needing another 3 or 4 miles of range on my car, it's pretty clear that car panels aren't an economically viable option yet.  They do make a nice sales gimmick for the math-challenged.

[wraper]

You also have to calculate the cost of the battery into the fuel costs because batteries don't have an eternal life.

It's basically equal with vehicle life. Unless you buy crappy Nissan leaf without battery thermal management system. What's for sure they last more than gasoline engines in average. Which is not eternal at all, especially in modern cars where they get pushed to the max while trying to make them cheap at the same time.

Governments earn big bucks from tax on fuel. Do you really think they will let that milk cow go away (*)?

When that happens, they will need to implement something for every car, not just EV. It won't be trivial to implement tax on electricity in a whole. Also by the time when that happens, EV price should go down to ICE level.

[wraper]

Is putting solar panels on an EV a good idea?

Already done: https://sonomotors.com/de/sion/
Toyota, Kia and Hyundai use solar panels for the next generation of BEV and PHEV.
https://www.electrive.com/2019/07/04/toyota-testing-hybrid-prius-fitted-with-solar-cells/

wraper mentioned stupid, are Toyota, Kia and Hyundai stupid or just ahead of the rest of the stupid other EV manufacturers ?

Especially Toyota with their hydrogen dead end.

[hendorog]

Is putting solar panels on an EV a good idea?

Already done: https://sonomotors.com/de/sion/
Toyota, Kia and Hyundai use solar panels for the next generation of BEV and PHEV.
https://www.electrive.com/2019/07/04/toyota-testing-hybrid-prius-fitted-with-solar-cells/

wraper mentioned stupid, are Toyota, Kia and Hyundai stupid or just ahead of the rest of the stupid other EV manufacturers ?

I think "not practical" would be a more diplomatic term than "stupid", but wraper doesn't mince words.  The Prius mentioned uses very expensive multi-junction cells (34% efficiency is still pretty expensive) and is a concept test car.  It isn't an economically viable solution yet.  The Sion, AFAIK, is vaporware and I haven't seen a justification for their remarkable claim of 34km/day (in Deutschland no less), so we'll wait and see. 

Meanwhile, my 30 panels on the roof have each been producing that 1.2kWh/day for the past 7 years at a cost that is probably less than 10% of what the equivalent solar panel system on a car would be.  Unless I were desperately needing another 3 or 4 miles of range on my car, it's pretty clear that car panels aren't an economically viable option yet.  They do make a nice sales gimmick for the math-challenged.

How do you charge your car from your solar panels? My car is not at home when the sun is shining.

[coppice]

EVs actually pay over for themselves. Both from larger initial carbon footprint standpoint and lifetime fuel cost.

The comparisons I have seen so far are highly questionable. Like comparing a RAV4 with an e-Niro, and finding the lifetime cost of the e-Niro is slightly lower. Maybe they could have tried two cars of a similar size, like an e-Niro and a non electric Niro. If that produced good lifetime costs for the electric version it might be a bit more impressive.

[bdunham7]

How do you charge your car from your solar panels? My car is not at home when the sun is shining.

My car often is home whilst the sun shines--but I charge at night.  Thanks to the Electric Grid Bank of Southern California Edison my daytime generated kWh are worth 3X what the night ones are, so on an economic basis, the roof panels are actually 3X more cost effective than even my earlier statement. 

[james_s]

Have the solar panels feed into the grid during the day when they produce excess capacity, charge your car when you get home at night pulling power from the grid during what is then off-peak.


Solar panels on cars is a fairly dumb ideal, although things are getting to the point where I would welcome virtually any car that is remotely unique amongst the sea of bland generic crossovers, fake SUVs that try to be everything and end up doing nothing well and yet they are extremely popular for reasons I will never really understand. It doesn't even really matter what you buy anymore, it's all the same car with a different logo on it.

https://medium.com/swlh/the-zombie-mobile-b03932ac971d

[hendorog]

Governments earn big bucks from tax on fuel. Do you really think they will let that milk cow go away (*)?

Just tax sunlight.

Adding solar panels also means adding the electronics to step up the output voltage so it can charge the traction battery. That will introduce quite a lot of losses. The best idea I have heard of is car mounted solar panels charging the 12 V battery but it all does sound like solar roadways in a new guise.

So in my country we convert the dam power to HV AC, transport it hundreds of km's, change it to HV DC, under a bit of sea, back to AC again, transport another few hundred kms, mix it in with other power to the biggest city.

[bdunham7]

The comparisons I have seen so far are highly questionable. Like comparing a RAV4 with an e-Niro, and finding the lifetime cost of the e-Niro is slightly lower. Maybe they could have tried two cars of a similar size, like an e-Niro and a non electric Niro. If that produced good lifetime costs for the electric version it might be a bit more impressive.

Most comparisons of electric vs gas cars, in whatever aspect, are highly questionable.  The cost of owning a Tesla (any Tesla) for example are sky-high compared to say a Honda Accord--and the Accord arguably has significant advantages for some people.  However, a premium Model S or X costs a lot less than a Ferrari or a Bentley---and also arguably has advantages over those.  So what do you compare it to and how?  The answer is different for every driver--and "cost" is not the main driving factor for most people.

[hendorog]

Have the solar panels feed into the grid during the day when they produce excess capacity, charge your car when you get home at night pulling power from the grid during what is then off-peak.

Ah so you must have a subsidised feed in tariff. Lucky you.

If everyone does what you do, will your approach still work?

Solar panels on cars is a fairly dumb ideal, although things are getting to the point where I would welcome virtually any car that is remotely unique amongst the sea of bland generic crossovers, fake SUVs that try to be everything and end up doing nothing well and yet they are extremely popular for reasons I will never really understand. It doesn't even really matter what you buy anymore, it's all the same car with a different logo on it.

https://medium.com/swlh/the-zombie-mobile-b03932ac971d

That is one reason why I drive an old car. It has more character.

[james_s]

Have the solar panels feed into the grid during the day when they produce excess capacity, charge your car when you get home at night pulling power from the grid during what is then off-peak.

Ah so you must have a subsidised feed in tariff. Lucky you.

If everyone does what you do, will your approach still work?

Solar panels on cars is a fairly dumb ideal, although things are getting to the point where I would welcome virtually any car that is remotely unique amongst the sea of bland generic crossovers, fake SUVs that try to be everything and end up doing nothing well and yet they are extremely popular for reasons I will never really understand. It doesn't even really matter what you buy anymore, it's all the same car with a different logo on it.

https://medium.com/swlh/the-zombie-mobile-b03932ac971d

That is one reason why I drive an old car. It has more character.

I don't personally have solar, but I know people who do and they get paid for energy they generate during the day.

If everyone did that then no, it probably wouldn't work out well but we are not in a situation where anywhere close to everyone is doing it so that is not a problem. If things shift to where too many people are doing it then economic realities will push them in a different direction and it will work out.

I too drive an older car, it will turn 30 next year and it is getting to where I worry something will happen to it and I won't be able to find parts. If I had space to keep them I would buy up and hoard several more, or if I could buy a brand new 80s-90s car today I would. Cars have been bland and boring for the past 15 years or so and getting worse all the time. I really don't even know what I would buy later on if I had to because looking at what is available brand new today I cannot actually think of anything out there that I would want even if it was given to me for free. Car manufactures fret that young people are not as interested in cars as older generations but it's no surprise why, cars are so boring now, there is nothing unique, no character, no individuality, nothing inspiring, why would any kid growing up today be into cars?

[nctnico]

The comparisons I have seen so far are highly questionable. Like comparing a RAV4 with an e-Niro, and finding the lifetime cost of the e-Niro is slightly lower. Maybe they could have tried two cars of a similar size, like an e-Niro and a non electric Niro. If that produced good lifetime costs for the electric version it might be a bit more impressive.

Most comparisons of electric vs gas cars, in whatever aspect, are highly questionable.  The cost of owning a Tesla (any Tesla) for example are sky-high compared to say a Honda Accord--and the Accord arguably has significant advantages for some people.  However, a premium Model S or X costs a lot less than a Ferrari or a Bentley---and also arguably has advantages over those.  So what do you compare it to and how?  The answer is different for every driver--and "cost" is not the main driving factor for most people.

I'd say cost is everything to most drivers. If you look carefully then you'll see that the market for EVs are artificially created by government incentives (even in China where it is easier to get a permit for an electric car compared to an ICE care). Take the incentive away and sales drop to zero. In the Netherlands the sales of the Tesla Model-S went from about 2000 a year until 2018 to 99 in 2019 (so far). 2018 shows a very large sales peak due to the government incentive being stopped in 2019. Other higher end EVs like the Jaguar I-pace show similar trends. People aren't buying EVs because they like them but because they want to drive around cheap due to the government incentives.

[bdunham7]

Ah so you must have a subsidised feed in tariff. Lucky you.

If everyone does what you do, will your approach still work?

Not subsidized per se, in my case--although it is a money-loser for the utility company.  The rule is that SCE has to pay me the exact same amount that they would charge me for the electricity at the time it is provided.  So I've chosen a TOU (Time Of Use) plan that has much higher rates in the day and reasonable (not low) rates at night. My air conditioner would cost $3.00 per hour to run on this rate if I didn't have the solar system.   

Solar generally helps meet the greater daytime demand.  There is an issue called the "duck curve" that has resulted from adoption of solar,  but I think it is more due to commercial solar than private rooftops.  This has resulted in SCE pushing the peak periods later in the day in an attempt to charge me some money, as the evenings have high demand but less solar production.  The answer is that if everyone did it, there would have to be some storage involved either at the utility level or at the home level.  The products are available (Powerwall, etc) but they don't make economic sense yet. 

[wraper]

Other higher end EVs like the Jaguar I-pace show similar trends. People aren't buying EVs because they like them but because they want to drive around cheap due to the government incentives.

Nope, they buy them exactly because they like them. And incentives help buying what they probably would have trouble to afford otherwise. If you just want to drive cheap, Model S/X is very far from something you would go for, even with incentives.

[bdunham7]

I'd say cost is everything to most drivers. If you look carefully then you'll see that the market for EVs are artificially created by government incentives (even in China where it is easier to get a permit for an electric car compared to an ICE care). Take the incentive away and sales drop to zero. In the Netherlands the sales of the Tesla Model-S went from about 2000 a year until 2018 to 99 in 2019 (so far). 2018 shows a very large sales peak due to the government incentive being stopped in 2019. Other higher end EVs like the Jaguar I-pace show similar trends. People aren't buying EVs because they like them but because they want to drive around cheap due to the government incentives.

If cost is the main concern, then Tesla drivers must be bad at math.  As I said, it is much, much more expensive to drive a Tesla than an equivalent-sized Honda.  People may indeed respond to incentives, but that doesn't mean that the cost is actually lower.  Can you say that someone who is willing to spend $50K extra to get a $7500 tax break is "cost sensitive"--or is it something else?  Among EV owners I know, the only cost sensitivity is a form of self-delusion that was needed to talk themselves into an expensive and unnecessary purchase.

[nctnico]

Other higher end EVs like the Jaguar I-pace show similar trends. People aren't buying EVs because they like them but because they want to drive around cheap due to the government incentives.

Nope, they buy them exactly because they like them. And incentives help buying what they probably would have trouble to afford otherwise. If you just want to drive cheap, Model S/X is very far from something you would go for, even with incentives.

Then explain to me why people stop buying them when the incentives go away. Why does that happen if people buy the cars because they like them? The incentives go away and the sales numbers go to zero. How do you explain that?

[hendorog]

Ah so you must have a subsidised feed in tariff. Lucky you.

If everyone does what you do, will your approach still work?

Not subsidized per se, in my case--although it is a money-loser for the utility company.  The rule is that SCE has to pay me the exact same amount that they would charge me for the electricity at the time it is provided.  So I've chosen a TOU (Time Of Use) plan that has much higher rates in the day and reasonable (not low) rates at night. My air conditioner would cost $3.00 per hour to run on this rate if I didn't have the solar system.   

Solar generally helps meet the greater daytime demand.  There is an issue called the "duck curve" that has resulted from adoption of solar,  but I think it is more due to commercial solar than private rooftops.  This has resulted in SCE pushing the peak periods later in the day in an attempt to charge me some money, as the evenings have high demand but less solar production.  The answer is that if everyone did it, there would have to be some storage involved either at the utility level or at the home level.  The products are available (Powerwall, etc) but they don't make economic sense yet.

You have such a biased situation with your 3X factor mentioned earlier, that you could probably make a powerwall pay - ignore the solar, just suck at night and blow during the day.

[wraper]

Other higher end EVs like the Jaguar I-pace show similar trends. People aren't buying EVs because they like them but because they want to drive around cheap due to the government incentives.

Nope, they buy them exactly because they like them. And incentives help buying what they probably would have trouble to afford otherwise. If you just want to drive cheap, Model S/X is very far from something you would go for, even with incentives.

Then explain to me why people stop buying them when the incentives go away. Why does that happen if people buy the cars because they like them? The incentives go away and the sales numbers go to zero. How do you explain that?

Because they are luxury cars which cost an arm and a leg. Full price is way too much for most people. Aso many people who wanted EV likely have chosen to wait because of cheaper model 3 coming out.

[nctnico]

I'd say cost is everything to most drivers. If you look carefully then you'll see that the market for EVs are artificially created by government incentives (even in China where it is easier to get a permit for an electric car compared to an ICE care). Take the incentive away and sales drop to zero. In the Netherlands the sales of the Tesla Model-S went from about 2000 a year until 2018 to 99 in 2019 (so far). 2018 shows a very large sales peak due to the government incentive being stopped in 2019. Other higher end EVs like the Jaguar I-pace show similar trends. People aren't buying EVs because they like them but because they want to drive around cheap due to the government incentives.

If cost is the main concern, then Tesla drivers must be bad at math.  As I said, it is much, much more expensive to drive a Tesla than an equivalent-sized Honda.  People may indeed respond to incentives, but that doesn't mean that the cost is actually lower.  Can you say that someone who is willing to spend $50K extra to get a $7500 tax break is "cost sensitive"--or is it something else?  Among EV owners I know, the only cost sensitivity is a form of self-delusion that was needed to talk themselves into an expensive and unnecessary purchase.

In the Netherlands EVs primarily get bought as corporate lease cars. Employers pay a monthly fee to make a car available for the employee. Depending on the position of the employee there is a certain budget. The employee gets tax added to the income which is a certain percentage of the price of the car. If the tarif is low the employee pays less compared to an ICE based car. Starting from 2019 the low tarif has been cancelled for cars over 50k euro. Next year the EV tarif is increased to 8% (was 4%) and the maximum price will be 45k euro. The low tarif costs too much money already so it had to be changed.

[hendorog]

The comparisons I have seen so far are highly questionable. Like comparing a RAV4 with an e-Niro, and finding the lifetime cost of the e-Niro is slightly lower. Maybe they could have tried two cars of a similar size, like an e-Niro and a non electric Niro. If that produced good lifetime costs for the electric version it might be a bit more impressive.

Most comparisons of electric vs gas cars, in whatever aspect, are highly questionable.  The cost of owning a Tesla (any Tesla) for example are sky-high compared to say a Honda Accord--and the Accord arguably has significant advantages for some people.  However, a premium Model S or X costs a lot less than a Ferrari or a Bentley---and also arguably has advantages over those.  So what do you compare it to and how?  The answer is different for every driver--and "cost" is not the main driving factor for most people.

I'd say cost is everything to most drivers. If you look carefully then you'll see that the market for EVs are artificially created by government incentives (even in China where it is easier to get a permit for an electric car compared to an ICE care). Take the incentive away and sales drop to zero. In the Netherlands the sales of the Tesla Model-S went from about 2000 a year until 2018 to 99 in 2019 (so far). 2018 shows a very large sales peak due to the government incentive being stopped in 2019. Other higher end EVs like the Jaguar I-pace show similar trends. People aren't buying EVs because they like them but because they want to drive around cheap due to the government incentives.

I have to say that here we are seeing rapid growth of EV's. They are still a small proportion of the entire fleet though - about 12000 out of 3.9 million or so.

The only incentive to date has been that you pay no road user charges on EV's. In NZ that is a tax on vehicles which don't use petrol - as the petrol is already includes this tax. Diesel doesn't have this tax and so road based diesel vehicles pay an extra tax separately.

A new incentive has been added for low emission vehicles which will take effect in a couple of years. Up to $8k discount when they are sold in NZ for the first time.

[tautech]

There’s another elephant in the room you may have overlooked.

Dare to name it?

Sure.
Namely the 'big picture' reason why EV technology has even been developed, atmospheric pollution.

So the planet has come up with this wonderful solution of EV's that require charging with power from fossil fueled power stations.  And it would seem most have totally ignored the incorporation of PV. 

The result, another ~5km of EV range charge/EV is loaded onto grids and required to be generated when it could well have been harnessed from the sun free !

[wraper]

The result, another ~5km of EV range charge/EV is loaded onto grids and required to be generated when it could well have been harnessed from the sun free !

If you put PV worth the same amount of money onto roof, you would get way more electricity to charge the car and power other stuff. So I can argue that this crappy use of PV takes money away from where it actually matters and basically wastes it.

[nctnico]

That only works if you have a roof to put panels on. That is a small but significant detail.

And the more I think of it the better I like the idea of an EV which at least covers the self-discharge of the batteries by having a small solar panel on the roof. You can leave it parked with a nearly empty battery without needing to worry about the batteries getting drained completely.

[tautech]

The result, another ~5km of EV range charge/EV is loaded onto grids and required to be generated when it could well have been harnessed from the sun free !

If you put PV worth the same amount of money onto roof, you would get way more electricity to charge the car and power other stuff. So I can argue that this crappy use of PV takes money away from where it actually matters and basically wastes it.

But you presume everyone owns a roof to place PV panels on.