Why not drive a Tesla?

I really don't know the answer to this. As you say, your actual electrons are coming from wherever, it's an 'accounting thing', but that's fine if the end goal is met. But is it? I don't know.

It's hard for me to believe that they wouldn't sell that wind power if you didn't sign up for it. So I can't see how these contracts can be considered as being responsible for that amount of energy being 'green'. But does your contract help them to get a higher price overall? Does that help encourage more wind energy installations? If so, I guess it helps, but in a sort of indirect way?

I suspect it's more of a feel good kind of thing, but there might be something to it.

-ERD50


In Texas you buy your own electricity from a number of producers or resellers....

So, I have an option to buy from someone who produces using normal methods such as coal or gas... or I can buy from someone who produces 'renewable'.... this past time I chose I bought renewable....


Now, sure, they would sell it to SOMEONE, but that does not mean that I am not purchasing green energy.... if I use 50 KWH then the company I am paying has to put 50 KWH of energy into the grid for my benefit... if I use nothing then they put nothing in the grid for me... if they have not yet sold all of their production to retail customers then I would bet they are selling it on the wholesale market... BUT, I am paying for the production of renewable energy for MY use...


I have heard where the spot price of green energy has gone to zero.... there was once a headline that said it went negative....

So, where do you think they would rather sell their production... to retail customers or to utilities?
 
I was aware that much/most of Canada had a lot of hydro. A few comments on that - first, hydro is somewhat controversial as a 'green' source. Yes, no fuel is burnt, but there was a lot of environmental destruction in damming the rivers to provide the reservoir, and that is claimed to create a large carbon emission from loss of plant life (which all decayed, releasing its carbon in the process), and in all the cement required (very carbon intensive). I've read sources that say a hydro plant is carbon negative for something like 90 years! -ERD50

I find it hard to believe that it takes a hydro plant 90 years to negate the environmental impact of its construction. What is the source of that claim? And, if that's really true, then how does a wind turbine ever pay for itself?
 
I find it hard to believe that it takes a hydro plant 90 years to negate the environmental impact of its construction. What is the source of that claim? And, if that's really true, then how does a wind turbine ever pay for itself?

I'll see if I can find the source, but like I said, I was just going from memory, 'something I read', and I'm not sure of the veracity of the claim. But hydro does have an issue with carbon (or more accurately, green-house gas, as methane is involved, and that's many times worse than carbon).

Here is something I found though:

Progress in the studies on the greenhouse gas emissions from reservoirs - ScienceDirect

The global warming potential (GWP) of the GHG emissions from Brazil’s reservoirs are amazing, which are even higher than that from thermal power plants with similar installed capacity [2]. For example, Curuá-Una Reservoir in Brazil emitted 3.6 times more GHGs than those would have been emitted by generating the same amount of electricity from oil [7]. However, GHG emissions from Canadian reservoirs are relatively low [8], which are lower than the GHG emissions compared with GHGs emitted by fossil-fuelled electricity generation. Therefore, it cannot be generalized to determine whether the development of hydroelectricity could reduce GHG emissions, which should depend on the specific situation of reservoirs.

A wind turbine doesn't flood an area. That's where a lot of the GHG is from. The plant crops right under it. Though a turbine does have a large concrete base, don't know how that compares versus a dam on a lifetime concrete-GHG per MW-hr production.

In Texas you buy your own electricity from a number of producers or resellers....

So, I have an option to buy from someone who produces using normal methods such as coal or gas... or I can buy from someone who produces 'renewable'.... this past time I chose I bought renewable....

I have heard where the spot price of green energy has gone to zero.... there was once a headline that said it went negative....

So, where do you think they would rather sell their production... to retail customers or to utilities?

As I said, I really don't know how this works from production to customer. Are they really selling it direct to you? I think it's more complex than that. Again, I'm not saying it is a bad thing at all, I'm just not sure it makes a difference or not. I suspect (but do not know) that they scrape a little bit off the top with this marketing approach, making a little profit from people or companies that want to say they are being green? I dunno, maybe it really does help support more wind power?

I think the negative/zero spot prices involve some sort of subsidy at the production level, where they get credit for every MW-hr produced, so if the negative sale is less negative than the subsidy, they sell it to net a (small) profit. Otherwise, they can turn those turbines 90 degrees to the wind and put the brakes on, and save some wear and tear. Why would they sell it for a (net) loss?

-ERD50
 
In Texas you buy your own electricity from a number of producers or resellers....

So, I have an option to buy from someone who produces using normal methods such as coal or gas... or I can buy from someone who produces 'renewable'.... this past time I chose I bought renewable....


Now, sure, they would sell it to SOMEONE, but that does not mean that I am not purchasing green energy.... if I use 50 KWH then the company I am paying has to put 50 KWH of energy into the grid for my benefit... if I use nothing then they put nothing in the grid for me... if they have not yet sold all of their production to retail customers then I would bet they are selling it on the wholesale market... BUT, I am paying for the production of renewable energy for MY use...


I have heard where the spot price of green energy has gone to zero.... there was once a headline that said it went negative....

So, where do you think they would rather sell their production... to retail customers or to utilities?

Actually the way the Texas Grid is set up now there are a number of nodes where the price is set in 15 min intervals for spot purchase. You do see some of the nodes that have a lot of wind generation go negative when the wind is turning the turbines hard. Not the entire grid since at most Tx is running in spring and fall 40% wind for in the late night. As of June 1 the total wind capacity of the Texas Grid was 19079 mw. The lowest loads one sees at 4 am are about 25000 mw, where peak demand for may was 59244mw. (so a 2 to1 demand swing). Solar will be 1317 mw by the end of the year, increasing to 2655 mw by the end of 2020.

There are actually several different markets for electricity in Tx a Day Ahead market where retailers buy most of the needed energy the next day and a real time market where power usage is trued up. The negative prices occur on the real time market. You can find out a lot more if interested on the ERCOT web site Electric Reliability Council of Texas.
 
Did this thread get off subject somewhere? I keep looking for why people drive a Tesla. :D
What's a Tesla? :confused:

Oh, here you go:

https://en.wikipedia.org/wiki/Tesla_(unit)

The tesla (symbol T) is a derived unit of the strength of a magnetic field in the International System of Units.

One tesla is equal to one weber per square metre.

I thought a Weber was a grill? Cars have grills, is that the connection? Sounds like it would be crowded, with one of those grills every square meter (the old charcoal Weber we have is round). Might need an AutoPilot system to keep from running into each other. Doesn't sound very fun to drive to me.

-ERD50
 
/snip/

As I said, I really don't know how this works from production to customer. Are they really selling it direct to you? I think it's more complex than that. Again, I'm not saying it is a bad thing at all, I'm just not sure it makes a difference or not. I suspect (but do not know) that they scrape a little bit off the top with this marketing approach, making a little profit from people or companies that want to say they are being green? I dunno, maybe it really does help support more wind power?

I think the negative/zero spot prices involve some sort of subsidy at the production level, where they get credit for every MW-hr produced, so if the negative sale is less negative than the subsidy, they sell it to net a (small) profit. Otherwise, they can turn those turbines 90 degrees to the wind and put the brakes on, and save some wear and tear. Why would they sell it for a (net) loss?

-ERD50


Does it really matter how it works:confused: By that thinking none of the wind is a benefit since nobody is using it directly... or solar for that matter...

I would say think of it as a bucket of water... there are a number of sources that pour water into the bucket and I have a small pipe where I can take water out... I pay someone to put water into the bucket.... they are required to put in as much as I draw out... there is no way to follow the molecules of water to me... but I am sure that the bucket would not be filled for my part without me paying for it....


NOW, you seem to think that one producer will fill up that bucket no matter what... so what I buy is not a benefit since you cannot trace it to me.... but I would bet a million bucks that if that producer was NOT being paid somehow for filling up the bucket by me and other consumers he would not fill it up at all...


SO, there is a direct correlation from the producer to the consumer for green energy... if nobody is buying it nobody is producing it... I am just one of many who is buying...
 
I agree. Still waiting to hear from anyone who bought a tesla and is sorry they did.

Before I bought mine I did some searching about who doesn't like their tesla. I found a post on another site titled "I hate my tesla". I read on and the guy said that he hates his tesla because he never wants to drive his $250,000 farrari.
 
RE - buying wind energy at the consumer level:

Does it really matter how it works:confused: ...
No. It's just one of those many things I'm curious about, and would kind of like to understand.


Texas Proud; said:
By that thinking none of the wind is a benefit since nobody is using it directly... or solar for that matter...

I don't see how that follows. As long as the renewables are sold and utilized, we all benefit from the cleaner energy. As I know you understand based on your previous comments, it doesn't matter where it is used on the grid, energy on the grid can be looked at as being 'fungible' in the same way money is. But we can, and do, use accounting to keep track of it.

All I'm doing is questioning the role of these consumer contracts in promoting more solar/wind. Maybe they do help, but I'm not sure. It may be too complicated to understand w/o a lot of work, so maybe I'll never know.

IOW, it can all be bought/sold at the commercial level. Do we need contracts at the consumer level to assure it will be used? I don't think so, as I get to choose my supplier here, and I don't specify the mix of coal, NG, nukes and renewables - the grid operators do that w/o me specifying it. And it still gets done.


NOW, you seem to think that one producer will fill up that bucket no matter what... so what I buy is not a benefit since you cannot trace it to me.... but I would bet a million bucks that if that producer was NOT being paid somehow for filling up the bucket by me and other consumers he would not fill it up at all...

Not 'no matter what', they fill it up if they can get paid for it - I just think this can happen at the commercial level, just like the coal, NG, nuke and RE does now, w/o, as far as I know, any consumers saying "I want coal energy", or "I want nuke energy", or "I want NG energy". If we don't need consumer contracts for those to be viable, why do we need them for wind/solar?.

But as I said, maybe these contracts do provide a little extra profit to the RE sources, and maybe that does help promote more RE installations. All I'm saying is I don't know if that is the case or not.

-ERD50
 
Still working on getting back to some of the open requests, been busy, but here's a little info to chew on until I have more time:

Some questions about efficiency of combined cycle turbines in producing juice for EVs, my calcs are from older data, but it looks like it hasn't changed much, the source has more recent data:

https://www.eia.gov/electricity/annual/html/epa_08_02.html

my calc:

To express the efficiency of a generator or power plant as a percentage, divide the equivalent Btu content of a kWh of electricity (which is 3,412 Btu) by the heat rate.

So in practice, NG CC is only ~ 44.5% ?

Gen | Heat Rate | BTU | Eff%
coal/steam | 10089 | 3412 | 33.82%
NG combined cycle | 7667 | 3412 | 44.50%
NG/steam |10354 |3412 |32.95%
NG/Gas Turbine |11371 |3412 |30.01%

The add in grid loss, and losses in obtaining NG, compared to losses in obtaining/transporting gasoline.

And here's a chart I've posted before that shows how bad an EV on coal is. You can use these figures to weight some smaller % of coal and NG, and see that even a little coal in the mix is not good for the EV versus a hybrid. The EV on natural gas is a bit better than a hybrid, but not by a large factor. And I'd think hybrids have improved since this report, and can continue to improve, while I think EVs, already at very high eff%, don't have a lot of room for improvement. I think the ~300 w-hr/mile has been pretty stagnant?

No more time to dig into it right now, just some data for your enjoyment! :)

http://www.pnas.org/content/111/52/18490.full

-ERD50
 

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Thanks for continuing the dialog. I've been pretty busy too and will be even busier soon with summer vacations. I just have a few quick thoughts.

And I'd think hybrids have improved since this report, and can continue to improve, while I think EVs, already at very high eff%, don't have a lot of room for improvement. I think the ~300 w-hr/mile has been pretty stagnant?

I understand your data is starting to support this emissions picture:

  • Overall, EVs are only a bit better than gasoline cars
  • Overall, EVs are barely better, and often times worse than hybrids

Hybrid vehicle efficiency have been getting better because they are getting higher and higher capacity batteries. Basically, the ICE-to-Electric ratio of the drivetrain is getting smaller -- Less ICE-ness, more EV-ness. The hybrid vehicle's efficiency will simply approach the EV at the vehicle/drivetrain level.

Keep in mind that all the electricity the (non-plugin) hybrid uses originates from gasoline and the internal combustion engine. Your data supposedly shows that this vehicle is overall better (emissions-wise) than a 100%-grid-connected EV.

Here's a thought experiment:

Suppose we buy a crate engine from a car manufacturer and the full set of exhaust and emissions-control setup of a regular ICE car. We install that at home and connect it to an electric motor to generate electricity to charge an EV. Now, this setup should act the same as the hybrid. Namely:

  • The vehicle is 100% powered by gasoline from the same supply chain
  • The vehicle can re-capture energy from regenerative braking

But intuitively, that doesn't seem like it would be better. Am I missing something?

And it wouldn't be limited to just the vehicle. The same gasoline engine from a regular car should also generate electricity for our homes. Also we would need to drive cars to the gas station to transport fuel home for these generators.

Very interested in your thoughts on this.

EDIT: I think it would be interesting to apply this thought experiment to not only emissions but also efficiency (your original comparison calculation of efficiency between the two).
 
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Actually the model I think makes sense is the Volt or a vehicle that can do about 50 mi on electricity, and then the gas engine kicks in. But actually for a hybrid the best improvements come from regenerative braking in stop and go traffic, (why the city mileage of a hybrid beats the highway mileage) Interestingly one thing that a lot of hybrids now do is to stay in electric in reverse since in general you don't drive that far or fast in reverse. More generally it stays in electric mode in parking lots etc.
One interesting fact I read is that if you can run an ICE at a constant speed it is more efficient than running at a variable speed. So you would decouple the engine from the drive shaft and have it just drive a generator. The volt unfortunately does have a mode where the engine directly drives the wheels.
One interesting question is how big an engine to run a constant speed generator to run at 70 mph?
 
Actually the model I think makes sense is the Volt or a vehicle that can do about 50 mi on electricity, and then the gas engine kicks in. But actually for a hybrid the best improvements come from regenerative braking in stop and go traffic, (why the city mileage of a hybrid beats the highway mileage) Interestingly one thing that a lot of hybrids now do is to stay in electric in reverse since in general you don't drive that far or fast in reverse. More generally it stays in electric mode in parking lots etc.
One interesting fact I read is that if you can run an ICE at a constant speed it is more efficient than running at a variable speed. So you would decouple the engine from the drive shaft and have it just drive a generator. The volt unfortunately does have a mode where the engine directly drives the wheels.
One interesting question is how big an engine to run a constant speed generator to run at 70 mph?

This is a very good point. One of the reasons for at least a portion of the inefficiency loss of automobile ICE engines is that they are required to perform across a large torque-curve range.

If they could instead be optimized to run at a single RPM and feed a battery bank and all-electric drive train, they could be made much more efficient. This is, in fact, how many railroad and marine propulsion systems are engineered and used today.
 
Before I get back to ken830, with his very interesting thought experiment:
Actually the model I think makes sense is the Volt or a vehicle that can do about 50 mi on electricity, and then the gas engine kicks in. But actually for a hybrid the best improvements come from regenerative braking in stop and go traffic, (why the city mileage of a hybrid beats the highway mileage) Interestingly one thing that a lot of hybrids now do is to stay in electric in reverse since in general you don't drive that far or fast in reverse. More generally it stays in electric mode in parking lots etc.
One interesting fact I read is that if you can run an ICE at a constant speed it is more efficient than running at a variable speed. ...

I agree, except for the 50 miles EV mode range - I think that is too much, and requires too big a battery. I think the optimum is just enough battery (lower cost/weight) for the conditions you state - short drives in a parking lot, backing up, etc. Avoid starting the ICE until it can run for a while rather than start/stop.


So you would decouple the engine from the drive shaft and have it just drive a generator. The volt unfortunately does have a mode where the engine directly drives the wheels.

Now I find this comment fascinating. Similar comments, with much wailing, were made all over the Internet when the Volt was announced. It gets back to what I said earlier - we should be technology agnostic and look for results.

So why exactly is it 'unfortunate' that the ICE drives the wheels directly? It isn't! Connecting the ICE to the wheels reduces energy consumption - and that is the goal. If the ICE does not drive the wheels directly, then you incur the losses of turning mechanical energy from the ICE into electrical energy, and then converting that electrical energy back to mechanical energy in the EV motor. That wastes about 20% of the energy, versus a few % in the drive train.

But many in the 'green' crowd were up in arms over this. Why? Because they are not technology agnostic and results oriented, they think in terms of "EV always > ICE" (they are 'in love' with the technology), so to them, an ICE driving wheels is bad. But physics says otherwise, and we should not argue with physics.

One interesting question is how big an engine to run a constant speed generator to run at 70 mph?

About 25 HP. We have big engines in cars to produce HP and torque for acceleration, we don't need it on average. You can reverse engineer this number pretty easily - lets use 60 mph (mile a minute) for easy math. A Tesla with an 85 kWh battery has a range of 265 mi (EPA). Say we get that going 60 mph (might be a bit higher/lower), we are driving for 265 minutes, that's 4.4 hours. 85 kWh/4.4 hours is 19.3 kW (hours factor out). 19.3 kW / 746 watts/HP = 25.87 HP.

Some of the answers to ken830's scenario are buried in there.

-ERD50
 
This is a very good point. One of the reasons for at least a portion of the inefficiency loss of automobile ICE engines is that they are required to perform across a large torque-curve range.

If they could instead be optimized to run at a single RPM and feed a battery bank and all-electric drive train, they could be made much more efficient. This is, in fact, how many railroad and marine propulsion systems are engineered and used today.

Agreed. And interestingly, the new Honda hybrid has no transmission:

Explaining the Honda Accord's Shrewdly Designed New Hybrid System – Tech Dept. – Car and Driver

Above 43 mph, the secondary motor spins the engine up to speed, and a clutch connects it to the drive wheels. ... A control computer adjusts engine load so it stays in its most efficient operating zone, but once the clutch is engaged, engine rpm is proportional to car speed.

So between 43 mph, and say 75 as a typical upper end cruising speed, means the engine works over only a 1.74:1 RPM range. I would think they could use a small, simple CVT with ~ 2:1 range (typically ~ 6:1 range in a most cars), and keep the engine at a constant RPM over a wider mph range. Since the electric motors handle the acceleration, my proposed CVT wouldn't need to handle much torque (the limiting factor in CVTs). Sure seems like you could do away with all this variable valve timing, and other complexities, and set the compression ratio higher (for higher efficiency), as you never need to deal with hard acceleration modes - the electric motors handle that.

And at a constant speed something like an HCCI mode ICE, or free-piston mode, is more attainable. Those have even higher efficiencies.

This is why I say hybrids still have opportunities for improvement, while I think EVs, being already so good in this regard, just due to their nature, are harder to improve upon. Yes, batteries will get better/cheaper, but efficiencies are near ideals already, not much room to grow.

-ERD50
 
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I always look at this economically.... and I said I would get back with a true cost comparison...

Hyundai now has an all electric car called the Ioniq... but it also is available as a hybrid... both are similar enough to an Elantra that I will group them together...


So the cost per Edmunds for the top of the line Limited..

Electric $33,385
Hybrid $27,721
ICE $18,891


So I calculated the cost of fuel to 100,000 miles... which is about when I get rid of cars..

Electric $2,857 at 10 cents per KWH
Hybrid $4,000 at $2.20 per gallon (55 mpg)
ICE $7,333 at $2.20 per gallon (30 mpg)...


So the extra cost to be green is...

Hybrid $5,497
Electric $10,018


Now, I did not include the sales tax on the cars, but that is not big... also, you would need to pay extra to get a good charger at home...

PLUS, the electric is only 124 mile range... now, this is enough to get me to almost all the place I would drive except for when going out of town...

The other problem is that the electric is ONLY available in California!!! Just read that...



OMG.... Just was clicking around before I posted this and saw that you can lease one for $305 per month and they will PAY for the electricity up to 50,000 miles!!! So fuel cost for the first 50,000 miles is free... this is an UNLIMITED miles 36 month lease.... if I had to drive a distance to and from work every day this might be the winner... can you not drive in the carpool lane by yourself if you are in an electric?


https://www.hyundaiusa.com/unlimited-plus
 
Actually the model I think makes sense is the Volt or a vehicle that can do about 50 mi on electricity, and then the gas engine kicks in. But actually for a hybrid the best improvements come from regenerative braking in stop and go traffic, (why the city mileage of a hybrid beats the highway mileage) Interestingly one thing that a lot of hybrids now do is to stay in electric in reverse since in general you don't drive that far or fast in reverse. More generally it stays in electric mode in parking lots etc.
One interesting fact I read is that if you can run an ICE at a constant speed it is more efficient than running at a variable speed.

FWIW, a hybrid takes advantage of the low speed torque of the electric motor to adapt the gasoline engine to be more efficient at highway speeds. Normally, this would not work well since the engine would be lousy at starting from a stop and accelerating at lower speeds. But with the aid of the electric motor that is no longer a problem. Thus, it can be adjusted to be more efficient at cruising and leave more of the work during accelerating to the electric motor.

Yes, there is no reverse gear. The hybrid just spins the electric motor backwards.

Mine has a switch that puts it into all-electric mode. That is good for slow travel (under 25 mph) on relatively level surfaces for about a mile. Needless to say, I don't use it much.

Finally, on cold mornings if I turn on the heater, the engine may run longer at stop lights, etc. before turning off. No surprise there. The heat still comes from cycling hot coolant through the heater core.
 
Thanks for continuing the dialog. I've been pretty busy too and will be even busier soon with summer vacations. I just have a few quick thoughts.
I understand your data is starting to support this emissions picture:

  • Overall, EVs are only a bit better than gasoline cars
  • Overall, EVs are barely better, and often times worse than hybrids
...

Try stating that on one of the EV or 'green' sites, and rather than trying to absorb it and analyze it, they'll act as if you just told them all their kids are ugly and stupid have dandruff and bad breath, and are bad dancers! :LOL: You will be virtually tarred-and-feathered!

ken830; said:
Hybrid vehicle efficiency have been getting better because they are getting higher and higher capacity batteries. ...

And also because they are learning to tweak the ICE for efficiency in this mode (and there are even more opportunities as I mentioned in the other posts). Hybrids are still a small enough % of total, so I think R&D is still catching up. There's inertia in existing tech.


ken830; said:
Here's a thought experiment:

Suppose we buy a crate engine from a car manufacturer and the full set of exhaust and emissions-control setup of a regular ICE car. We install that at home and connect it to an electric motor to generate electricity to charge an EV. Now, this setup should act the same as the hybrid. Namely:

  • The vehicle is 100% powered by gasoline from the same supply chain
  • The vehicle can re-capture energy from regenerative braking

But intuitively, that doesn't seem like it would be better. Am I missing something?
....

Very interested in your thoughts on this.

EDIT: I think it would be interesting to apply this thought experiment to not only emissions but also efficiency (your original comparison calculation of efficiency between the two).

Yes, very interesting thought experiment! Got the brain-juices flowing! So OK, I do think you missed some things, but some of them are positives - let's start there.

Lets call your idea a "remote series hybrid", it's like a series hybrid, but the ICE is remote from the vehicle.

As FIREmenow mentioned, a generator/ICE like that could run at one power/speed point, which simplifies the design, and can be further optimized for efficiency and emissions. And w/o needing to be mobile, you don't have the same weight/size constraints, so cost and efficiency might be improved there as well. And since timing is loose, you can do 'tricks', like say "I'm in no rush, so I will automatically turn on a small electric heater to preheat the catalytic converter for 10 minutes before starting, it won't use much power, but it will lower emissions." Maybe even pump the hot coolant into an insulated reservoir, keep it hot for the next day's run? All sorts of possibilities.

Oh, and if I were to do this, I'd be running that remote ICE on NG, so no trips to get gasoline, so even lower pollution (and lower refining costs, I think).

But...

It means the car is still a full EV, so needs enough batteries for range. Batteries = $$, weight and space.

And as I mentioned in the other post, you have the ICE-generator-generator-motor losses for every bit of power used. A series hybrid with a drive system between the engine and wheels for cruising modes eliminates those losses.

If the engineers can bring HCCI to market, that's really gonna move the goal posts for EVs. HCCI essentially brings diesel efficiencies to a gasoline engine, with lower emissions than even the gas engine. High efficiency w/o the pollution issues of diesels. Were talking eff% in the 40's instead of mid 20's. And the challenges mentioned in the video (getting the temperature inside the chamber just right), is easier on an engine that can be run in one range, and/or allowed to run in a special 'warm up before applying load' mode for a few minutes, which you can do if you have enough batteries for a few minutes of driving.

from wiki:
HCCI designs achieve gasoline engine-like emissions with diesel engine-like efficiency.

HCCI engines achieve extremely low levels of Nitrogen oxide emissions (NOx) without a catalytic converter.

And the video explanation:


You'd think they could put this technology at the power plants and gain eff% and lower emissions, but I think a piston engine just cannot compete with the simplicity and long life, low maintenance of a turbine. But turbines just can't achieve these efficiencies (except of combined cycle, but you need to be situated where you can use the lower grade heat).

-ERD50
 
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I always look at this economically.... and I said I would get back with a true cost comparison...

Hyundai now has an all electric car called the Ioniq... but it also is available as a hybrid... both are similar enough to an Elantra that I will group them together...


So the cost per Edmunds for the top of the line Limited..

Electric $33,385
Hybrid $27,721
ICE $18,891


So I calculated the cost of fuel to 100,000 miles... which is about when I get rid of cars..

Electric $2,857 at 10 cents per KWH
Hybrid $4,000 at $2.20 per gallon (55 mpg)
ICE $7,333 at $2.20 per gallon (30 mpg)...


So the extra cost to be green is...

Hybrid $5,497
Electric $10,018


Now, I did not include the sales tax on the cars, but that is not big... also, you would need to pay extra to get a good charger at home...

PLUS, the electric is only 124 mile range... now, this is enough to get me to almost all the place I would drive except for when going out of town...

The other problem is that the electric is ONLY available in California!!! Just read that...



OMG.... Just was clicking around before I posted this and saw that you can lease one for $305 per month and they will PAY for the electricity up to 50,000 miles!!! So fuel cost for the first 50,000 miles is free... this is an UNLIMITED miles 36 month lease.... if I had to drive a distance to and from work every day this might be the winner... can you not drive in the carpool lane by yourself if you are in an electric?


https://www.hyundaiusa.com/unlimited-plus

Even just purely taking your $10K difference, here in California, that difference is all made up by incentives (purely financial analysis in today's reality -- leaving out any feelings you may or may not have about direct-to-consumer incentives).

Single-occupancy carpool lane access is available in California, but I don't know about Texas.

This is actually something that I'm a bit annoyed with: The thing with these cars is that they are purely compliance cars, so the pricing that the consumer sees is really skewed. In the last couple of years, there has been some insane deals here in California for a lease of the Fiat 500e for $85 and then $49 per month! And considering savings on the fuel cost side, these cars effectively became cheaper-than-free for many people with a certain commute length --
can't be too long due to mileage limit and range limits, can't be too short because the fuel cost savings is minimal (and why lease a car if you don't drive).
 
Try stating that on one of the EV or 'green' sites, and rather than trying to absorb it and analyze it, they'll act as if you just told them all their kids are ugly and stupid have dandruff and bad breath, and are bad dancers! :LOL: You will be virtually tarred-and-feathered!



And also because they are learning to tweak the ICE for efficiency in this mode (and there are even more opportunities as I mentioned in the other posts). Hybrids are still a small enough % of total, so I think R&D is still catching up. There's inertia in existing tech.




Yes, very interesting thought experiment! Got the brain-juices flowing! So OK, I do think you missed some things, but some of them are positives - let's start there.

Lets call your idea a "remote series hybrid", it's like a series hybrid, but the ICE is remote from the vehicle.

As FIREmenow mentioned, a generator/ICE like that could run at one power/speed point, which simplifies the design, and can be further optimized for efficiency and emissions. And w/o needing to be mobile, you don't have the same weight/size constraints, so cost and efficiency might be improved there as well. And since timing is loose, you can do 'tricks', like say "I'm in no rush, so I will automatically turn on a small electric heater to preheat the catalytic converter for 10 minutes before starting, it won't use much power, but it will lower emissions." Maybe even pump the hot coolant into an insulated reservoir, keep it hot for the next day's run? All sorts of possibilities.

Oh, and if I were to do this, I'd be running that remote ICE on NG, so no trips to get gasoline, so even lower pollution (and lower refining costs, I think).

But...

It means the car is still a full EV, so needs enough batteries for range. Batteries = $$, weight and space.

And as I mentioned in the other post, you have the ICE-generator-generator-motor losses for every bit of power used. A series hybrid with a drive system between the engine and wheels for cruising modes eliminates those losses.

If the engineers can bring HCCI to market, that's really gonna move the goal posts for EVs. HCCI essentially brings diesel efficiencies to a gasoline engine, with lower emissions than even the gas engine. High efficiency w/o the pollution issues of diesels. Were talking eff% in the 40's instead of mid 20's. And the challenges mentioned in the video (getting the temperature inside the chamber just right), is easier on an engine that can be run in one range, and/or allowed to run in a special 'warm up before applying load' mode for a few minutes, which you can do if you have enough batteries for a few minutes of driving.

from wiki:

And the video explanation:

You'd think they could put this technology at the power plants and gain eff% and lower emissions, but I think a piston engine just cannot compete with the simplicity and long life, low maintenance of a turbine. But turbines just can't achieve these efficiencies (except of combined cycle, but you need to be situated where you can use the lower grade heat).

-ERD50

Great additions to my thought experiment. HCCI is especially interesting. I purposely left out a lot of the interesting possibilities to keep it simple. I wanted to keep focus on just the simple case. And I was aware that there are two major differences between a standard hybrid and our "remote series hybrid" (great concise & descriptive name, BTW):

  1. Efficiency Loss: ICE never drives wheels, therefore there exist efficiency loss from mechanical -> electrical -> chemical -> electrical -> mechanical
  2. Efficiency Gain: ICE can run at constant optimal RPM

Note: I acknowledge that you also stated that the EV requires extra cost, weight, and space. Let's ignore cost and space because we're just talking about emissions & efficiency. And weight could be somewhat ignored because the range of vehicle weights are still within the same ballpark -- so let's just do that for simplification.

What magnitude for each of these (#1 & #2) would you estimate? Are they close enough to cancel (and therefore ignore?)

Oh! And did you happen to see my "Edit"? If we do this same thought experiment for the home (taking the home off grid), that would get rid of the efficiency loss from multiple conversions. In reality, you would need at least a small energy storage device such as a battery, but for simplicity sake, assume a mostly constant load at home. So, would the "series hybrid home" case be better than the "grid-electric home"?

Should we (and by "we," I really mean "you," because I'm a bit lazy :D) start putting some numbers down? Or do we need to further define the variables and conditions?


QUICK SIDE NOTE: I'm really starting to enjoy our conversations now! And maybe it's just me, but I feel the tone of the entire thread is better too.
 
I agree. Still waiting to hear from anyone who bought a tesla and is sorry they did.

Before I bought mine I did some searching about who doesn't like their tesla. I found a post on another site titled "I hate my tesla". I read on and the guy said that he hates his tesla because he never wants to drive his $250,000 farrari.

I thought George Clooney was one.
 
This discussion got me thinking in a certain way, regarding ICE vehicle efficiency, but this doesn't seem right. Someone please check my math/assumptions:

A Tesla gets 265 miles on 85 kW-hr battery, that is ~321 watt-hours per mile. If the motor drive is 90% efficient, then 32.1 watt-hours/mile are wasted, and 289 watt-hours/mile are used to propel the car.

The Toyota Prius gets 44/40 mpg and gasoline contains 33,410 watt-hours/gallon. Using the lower 40 mpg #, it uses 835 watt-hours/mile. If the same 289 watt-hours/mile are required to propel that car, that means the ICE is 34.56% efficient - that's along way from the 20~25% number thrown around for ICE efficiency. So when you factor in other inefficiencies in producing the kWhr for an EV, the goal post has moved in recent years as hybrids improved. I think my earlier estimates were generous, 40% average eff% for grid, 92% eff in transmission on the grid *8% loss), 85% charge/idle efficiency, and 90% motor efficiency is ~ 28%. Yes, there are some other losses in getting the gasoline to the station, but there are also environmental costs in producing a large battery pack. I have not done a deep dive into those numbers, but from reasonable sources, I would say that they are at least not insignificant (if I am allowed a double negative!).

OK, I guess the numbers are right, the old "rule of thumb" number was probably for a car with lower mpg. So when you factor in other inefficiencies in producing the kWhr for an EV, the goal post has moved in recent years as hybrids improved.

Of course, a Prius is not a Tesla. They are not comparable. But all the EVs I've seen get similar watt-hour/mile figures. So if someone wants to tout the efficiency/environmental 'greenness' of an EV, I think they may have problems if they compare to available, affordable alternatives that anyone can own, regardless of driving patterns and/or charger availability.

If they want to compare the 'greenness' of a Tesla to some 5000 HP Lamborghini or something, they probably win!

-ERD50
 
Great additions to my thought experiment. HCCI is especially interesting. I purposely left out a lot of the interesting possibilities to keep it simple. I wanted to keep focus on just the simple case. And I was aware that there are two major differences between a standard hybrid and our "remote series hybrid" (great concise & descriptive name, BTW):

  1. Efficiency Loss: ICE never drives wheels, therefore there exist efficiency loss from mechanical -> electrical -> chemical -> electrical -> mechanical
  2. Efficiency Gain: ICE can run at constant optimal RPM

Note: I acknowledge that you also stated that the EV requires extra cost, weight, and space. Let's ignore cost and space because we're just talking about emissions & efficiency. And weight could be somewhat ignored because the range of vehicle weights are still within the same ballpark -- so let's just do that for simplification.

What magnitude for each of these (#1 & #2) would you estimate? Are they close enough to cancel (and therefore ignore?) ...

Yeah, probably close enough to wash out. There's lots of estimates in there, no reason to get hung up on any one of them.

Oh! And did you happen to see my "Edit"? If we do this same thought experiment for the home (taking the home off grid), that would get rid of the efficiency loss from multiple conversions. In reality, you would need at least a small energy storage device such as a battery, but for simplicity sake, assume a mostly constant load at home. So, would the "series hybrid home" case be better than the "grid-electric home"?

Should we (and by "we," I really mean "you," because I'm a bit lazy :D) start putting some numbers down? Or do we need to further define the variables and conditions?

Interesting idea, it got me thinking but it's getting way off topic! Maybe we can start another thread for home power?

Just quickly though (I gotta go plan my brew day for tomorrow, need to get a hoppy, but lower alc% APA going for summer), I was thinking you can't have a reasonably priced ICE running for 24/7, and storage has costs and losses. But (this is getting out there), imagine that you let the grid owner control when your ICE was generating, and you said they can run it up to a couple hours a day, enough to offset your consumption. That would give them peak capacity, and lower transmission loss (you power would go to your neighbors). And while it would be more difficult, what if that generator was your ('regular') hybrid (obviously, they can't start it in your closed garage!) - you get double use while not driving it?


QUICK SIDE NOTE: I'm really starting to enjoy our conversations now! And maybe it's just me, but I feel the tone of the entire thread is better too.

I'm enjoying the conversation as well. Though I don't feel the tone has changed, I just think maybe a couple of people were feeling 'victimized', when they were simply being challenged to back up their claims.

More later - i gotta go (OK, one quick note to tim59).

-ERD50
 
... Still waiting to hear from anyone who bought a tesla and is sorry they did. ...

Why are you waiting? Several people have explained that they don't expect that someone who spent that kind of money on a car did so w/o understanding what it can and cannot do. So I don't expect to find too many people who regret the purchase - and this forum is a pretty small sample size, a few owners that I know of. And it's a very impressive car.

So how is no one voicing regrets relevant to anything? Seems no more relevant than you claiming to have an MBA, or asking what kind of car I drive, or assuming I shorted Tesla (which I didn't)?

-ERD50
 
Re remote series hybrid, there is also a possible mode where the electric output of the generator goes directly to the motors that drive the car. (probably would be a selectable option)
 
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