Internal Combustion Engine has a future?

[gerntz]

If as many subsidies were given to development of ice cars as are given to electric ones I suggest their energy efficiency improvements would be similar.

 

[ERD50]

... Evs are running on (mostly) fossil fuel.
-ERD50

What's the basis of this claim regarding timing of EV charging? It sounds very much like motivated reasoning to me. ...

The basis is Logic and Math.

... BTW, I'm not an EV driver or advocate (I drive a good old ICE vehicle; one of the most power-dense ones made). I'm just describing the data & my thoughts regarding it.

Good, then hopefully you will have an open mind to this explanation, and challenge it if you find fault. It's actually quite simple, and I think the reason it is mostly ignored is it doesn't fit an 'agenda'.

... The best proxy for the 'clean-ness' of EV fuel is the overall 'clean-ness' of grid electricity where the EV user charges ...

It isn't about the timing of the charging - I only mentioned it as that is a likely scenario, and it is 'easy' on the grid, which has plenty of capacity at night, but not on a hot summer day with A/C blasting. My point is that the average mix of power sources on the grid is not a proxy for the 'clean-ness' of EVs on that grid. As I said, it is how the additional marginal KWhrs are produced. Lets try with numbers:

Picture a subset of the grid that consumes an average of 100 MW-hrs each day. And let's say this is a relatively 'clean' grid, with 30% coming from wind/solar ( I intentionally leave out hydro, as we really can't add much/any hydro in the US, and what we use is already accounted for, and some grids have little hydro anyhow). A kind of simple/stupid question to illustrate the point - Why isn't that grid @ 40% solar/wind? Obviously, because they just don't have anymore solar/wind available. If they did, they would use it, and that % would be higher. So we have:

100 MW-hrs produced/consumed per day
30 MW-hrs of that is from wind/solar​

So now imagine this area gets a lot of EVs, and demand goes up to 105 MW-hrs per day. Well, the 30 MW-hrs of solar/wind are already being consumed, they can't just 'crank up' the sun or the wind. So what do they do? They crank up the fossil fuel plants, that's all they can do, right? Following? So therefore, nearly ALL the electricity generated for the EVS was from fossil fuel. I fail to see how it could be otherwise.

Small caveat - you hear that there is occasionally an excess of wind on some grids at night. So that could be used to charge EVs. However, I think if you look at the numbers, that's a small and uncommon occurrence (it wouldn't make the news if it happened 3-4 times a week!). And if they added enough wind to make that routine, they'd have such extreme excesses on average, that it just doesn't seem cost effective (without that elusive/expensive storage that just doesn't exist).

And one pre-emptive comment - someone will say that the grid will have 5% more solar/wind when those EVs arrive. Great, but it doesn't change anything. The EVs are still an incremental increase - take the EVS away, and solar/wind would be even higher %. You still are burning fossil fuel to power the EV. Up until we have regular, routine excesses of solar/wind - IOW, over 100% renewables. Don't count on that.

I'll try to track down the numbers on fuel supply losses, I think the NAS chart I've published before captures that, but I'll need to review it.

-ERD50

 

[ERD50]

If as many subsidies were given to development of ice cars as are given to electric ones I suggest their energy efficiency improvements would be similar.

Not sure I'm following you. We are not seeing much in the way of energy improvements from EVs. Their efficiencies are already very high, there just isn't much room for improvement.

Batteries can be improved in cost and performance, but little in terms of efficiency.

The problem with overall efficiency in EVs is the ~ 30% efficiency of the power plants, and losses in the grid. I don't think there is much to be done with the efficiency of these turbines, they are well understood. They are conceptually simple devices, there just doesn't seem to be much to go after. The efficiency is what it is.

But the ICE is a complex deal, fuel mixtures, timing, a wave front of combustion doing all sorts of complex things and interactions with power, efficiency, and emissions. So oddly, that complexity provides opportunities for improvement - things are still far from optimized. Diesel efficiency is proof that the efficiency gains are possible (but Diesels have other drawbacks).

I generally dislike subsidies, but I think they can make sense "for the common good" if applied appropriately. But they should be technology agnostic. If the goal is "lower energy consumption", then who cares where it comes from -EV, ICE, building insulation, telecommuting, etc. Go for the goal, not the tech.

-ERD50

 

[samclem]

So now imagine this area gets a lot of EVs, and demand goes up to 105 MW-hrs per day. Well, the 30 MW-hrs of solar/wind are already being consumed, they can't just 'crank up' the sun or the wind. So what do they do? They crank up the fossil fuel plants, that's all they can do, right? Following? So therefore, nearly ALL the electricity generated for the EVS was from fossil fuel. I fail to see how it could be otherwise.

. . . .The EVs are still an incremental increase - take the EVS away, and solar/wind would be even higher %.

While I understand your reasoning ("the EVs are new load, add them to the 'top increment' of the needed supply"), I'm not sure it will be widely accepted. If I've got my EV plugged in and then turn on my electric oven, is the power for the EV charging really the last dirty bit of power that is made by burning coal, while the oven is powered by windmills? Why isn't the electricity for the oven (or any other load turned on) just as "dirty?" Yes, I can see that, on a monthly or annual basis, the EV load on the network is relatively recent, but is recency the best criteria for establishing which power source should be attributed to each load? For example, maybe a more logical approach is "baseline" load vs variable load. The EVs will presumably be a fairly steady requirement (folks have to drive to work) and would seem to count toward the baseline load, whereas air conditioners, heating, etc are more variable (depends on the weather that day) and should count toward the "need to fire up the coal burner" load. At least on a daily basis, if not a long-term "strategic" basis.

At any rate, from a public perception angle, using the "average" dirtiness of the grid (at a national, state, or local level) is probably the easiest method to explain/defend.

 

[ERD50]

While I understand your reasoning ("the EVs are new load, add them to the "top increment" of the needed supply"), I'm not sure it will be widely accepted. If I've got my EV plugged in and then turn on my electric oven, is the power for the EV charging really the last dirty bit of power that is made by burning coal, whilethe oven is powered by windmills? Why isn't the electricity for the oven (or any other load turned on) just as "dirty?" Yes, I can see that, on a monthly or annual basis, the EV load on the network is relatively recent, but is recency the best criteria for establishing which power source should be attributed to each load? For example, maybe a more logical approach is "baseline" load vs variable load. The EVs will presumably be a fairly steady requirement (folks have to drive to work) and would seem to count toward the baseline load, whereas air conditioners, heating, etc are more variable depends on the weather that day) and should count toward the "need to fire up the coal burner" load. At least on a daily basis, if not a long-term "strategic" basis.
At any rate, using the "average" dirtiness of the grid (at a national, state, or local level) is probably the easiest method to explain/defend.

Here's the difference I see:

It is about comparing the EV to available alternatives, and in the context of energy consumption and the environment, that alternative is a good mpg hybrid vehicle. So the comparison should include that marginal use, as that is just what it would be.

Most of the other loads you mention really don't have an alternative. And if they do, we can apply the same logic. So if you have NG or propane available as an alternative to your electric oven, the same math would apply, right? Though most people aren't thinking too much in terms of the environment with their oven, it probably doesn't add up to much, and the alternatives aren't available to everyone.

Does that help?

It also works to the positive the other way - any conservation of kWh we do, is mostly coming off the top in the same way. So conservation is cutting back almost entirely on fossil fuel, and increasing the % of 'green' on that grid. Conservation has the same leveraging effect in a positive way as increased usage has in the negative way.

And I'm not a fan of using the "easiest" explanation, if that distorts the case too much. And in this case, yes, I think it does. I often see the "easy" explanation taken, and the "Zero Tailpipe Emissions" (already too 'easy', IMO) becomes "Zero Emissions" - hey, what's not to like about that! Well, it's not true, and it's not helping us clean up the environment, and it drives bad decision making - that's what's not to like about it!

 

[meierlde]

Not sure I'm following you. We are not seeing much in the way of energy improvements from EVs. Their efficiencies are already very high, there just isn't much room for improvement.

Batteries can be improved in cost and performance, but little in terms of efficiency.

The problem with overall efficiency in EVs is the ~ 30% efficiency of the power plants, and losses in the grid. I don't think there is much to be done with the efficiency of these turbines, they are well understood. They are conceptually simple devices, there just doesn't seem to be much to go after. The efficiency is what it is.

But the ICE is a complex deal, fuel mixtures, timing, a wave front of combustion doing all sorts of complex things and interactions with power, efficiency, and emissions. So oddly, that complexity provides opportunities for improvement - things are still far from optimized. Diesel efficiency is proof that the efficiency gains are possible (but Diesels have other drawbacks).

I generally dislike subsidies, but I think they can make sense "for the common good" if applied appropriately. But they should be technology agnostic. If the goal is "lower energy consumption", then who cares where it comes from -EV, ICE, building insulation, telecommuting, etc. Go for the goal, not the tech.

-ERD50

Actually if you look at combined cycle gas plants the efficiency is up in the neighborhood of 60% 30% is typical for older coal plants.
Now 18 to 24% of energy goes into the motion of the car. However one should IMHO include in the useful energy that used to cool the car as well (since heat comes from waste heat in gas powered vehicles)

 

[ERD50]

Actually if you look at combined cycle gas plants the efficiency is up in the neighborhood of 60% 30% is typical for older coal plants.
Now 18 to 24% of energy goes into the motion of the car. However one should IMHO include in the useful energy that used to cool the car as well (since heat comes from waste heat in gas powered vehicles)

edit:

[-]Yes, but the combined cycle plants are a niche application. You have to be co-located where you can use that waste heat, and I don't think you get those efficiencies unless you are using it as baseline. If you need to throttle up/down (common for gas turbines), that affects the ability to use the co-gen heat. They just are not common, and probably wont be for a long, long time, if ever.[/-]

If you add their weighted contribution to the grid, I doubt you'd move the needle much at all.

edit - OK, they are more common than I thought -

https://www.eia.gov/todayinenergy/detail.php?id=25652

Combined-cycle plants, which are designed as an efficient hybrid of the other two technologies, accounted for 53% of gas-fired generation capacity and tend to be used more often than the other types of natural gas generators, as measured by capacity factors.

I'll need to look in more detail, but it looks like NG ~ 33%, so combined cycle is half of that, ~ 16%? So it would move the needle, but not so much?

Not sure about your last comment? Our mpg takes into account all the energy used and wasted (from the tank that is).

-ERD50

 

[meierlde]

Yes, but the combined cycle plants are a niche application. You have to be co-located where you can use that waste heat, and I don't think you get those efficiencies unless you are using it as baseline. If you need to throttle up/down (common for gas turbines), that affects the ability to use the co-gen heat. They just are not common, and probably wont be for a long, long time, if ever.

If you add their weighted contribution to the grid, I doubt you'd move the needle much at all.

Not sure about your last comment? Our mpg takes into account all the energy used and wasted (from the tank that is).

-ERD50

Note that combined cycle gas plants have heat recovery systems that make steam to drive a steam turbine providing electricity as well. It is this that gets you to the 60% neighborhood of efficency. As to being common this is by far the largest set of plants being installed and comes close to being equal to coal in power produced. The low price of gas and the short time to build mean they are the new power plant of choice. Actually it is interesting that the electric vehicles could well be charged at the low point of power usage for most days, 11 pm to 5 am. In addition your used battery bank, could be re purposed to a home battery bank to provide power between 4 pm and 8 pm (which is the typical peak load)

Here is a link to a report on the fuels used to generate electricty in the us:https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
Note natural gas is #1 at 33% coal is at 30%, nuclear 19.7, renewables (including hydro) 14.9% (hydro 6.5% wind 5.6% solar .9% etc)
The other fact is that load growth has slowed way down to less that 1% per year with the residential sector showing negative load growth (change in kinds of light bulbs are big here)

 

[Chuckanut]

Economics is a factor also. As much as I admire companies like Tesla that do new and different things I don't see a good reason why buyers of $70,000+ cars should get a tax subsidy.

Nor do I see a reason why they should not pay their fair share of the road taxes. IMHO, EV's will lose some luster when the states decide to hike up their fees in order to cover road expenses that gasoline taxes now cover. Why a person in a Telsa or Bolt should pay less to build and maintain the same road system as a person with a Chevy Cruise or a Toyota pickup truck is beyond me.

Heck! Why should a Hybrid driver like me pay less road tax than a person who drives the non hybrid version of my make and model? Oops... I may be getting to honest for my own good.

What it comes down to is a level playing field for all the auto options. I seem to have joined the ranks of the dangerous radicals.

 

[ERD50]

Note that combined cycle gas plants .... As to being common this is by far the largest set of plants being installed ...

Yes, thanks. I updated my post while you were typing, I went to 2x check my thoughts, and found they are more common than I thought.

I'll look at your other data later - thanks.

-ERD50

 

[Huston55]

The basis is Logic and Math.

Good, then hopefully you will have an open mind to this explanation, and challenge it if you find fault.

-ERD50

It seems we simply view the data differently. I don't agree with the "logic" that renewables are all/most of baseload & fossil fuels are all/mostly peak demand, and the "math" doesn't support that assertion.

1. The majority of baseload power comes from fossil & nuclear, not renewables.
2. The concept of "baseload" is currently being challenged and, with smart-grid and micro-grid technology in the near future, it will pretty much be a moot point; which means that total grid power source emissions are representative of EV emissions.
3. The capacity factors for fossil fuel generated power (coal & NG) are dramatically higher than for renewables (wind, solar, hydro), meaning that fossil sources are running more constantly (read: part of the baseload).
4. Combined cycle NG plants are not a "niche"; they account for 25% of US power production, which is forecasted to double in 20 yrs.

Having [-]said[/-] typed all this, what I find most interesting in this thread, and what I think could be the real game-changer, is the move from our individual vehicle ownership model to self-driving vehicles & ride-sharing. I understand that approx the same "miles" will be driven, just with fewer vehicles but, the efficiency implications (MPG, emissions, urban space utilization, reverse suburbanization, etc.) are fascinating.

 

[Geld ist Freiheit]

I would be interested to know how many Teslas and Priuseseses (Priae?) are tooling around MN. Weeks-months of freezing / sub-zero temps makes battery power less than attractive.
Maybe Senator can give us a quick census of EVs in MN.

 

[ERD50]

It seems we simply view the data differently. I don't agree with the "logic" that renewables are all/most of baseload & fossil fuels are all/mostly peak demand, and the "math" doesn't support that assertion.

1. The majority of baseload power comes from fossil & nuclear, not renewables. ...

I don't think it's a matter of agreeing/disagreeing - you haven't understood what I'm saying.

What I am saying isn't about baseload or peaking. As I said, it is that extra marginal kWh to charge an EV.

If EVs made up a significant % of night time charging (again, just the best and most common way they are to be charged on average), it would be pretty predictable on a large scale. The power companies will increase their baseload somewhat (it's generally the cheapest power for them), and that would be coal on many grids. To the extent it is predictable, they will use baseload power. But if it isn't, then it will be peaking fossil plants producing it. Either way, it's mostly coming from fossil.

Picture an extreme case with lots of wind power installed, on an evening where the wind is co-operating, and provides 80% of the power that night (averaged through the night). If there are no EVs on the grid, the other 20% is made up with fossil, right? And if we add another 5% from EV charging, ALL of that additional 5% has to come from fossil, right?

OK, that is a bit of a simplification, as I said before, to the extent we have an excess of wind that could be cleanly charging EVs. And at 80% average, you'd probably have peaks over that 100% line. But again, I just don't see where that would be happening routinely - wind its too variable, and it just isn't economical to overbuild to provide so much excess that you would get to have an excess available most of the time.

-ERD50

 

[ERD50]

...

Having [-]said[/-] typed all this, what I find most interesting in this thread, and what I think could be the real game-changer, is the move from our individual vehicle ownership model to self-driving vehicles & ride-sharing. I understand that approx the same "miles" will be driven, just with fewer vehicles but, the efficiency implications (MPG, emissions, urban space utilization, reverse suburbanization, etc.) are fascinating.

Yes, for example, we don't put many miles on our cars, so a hybrid just doesn't make economic sense for us. It probably doesn't make environmental sense either, due to the extra energy to make the batteries and motor. We may never 'amortize' that initial environmental cost over the life of the car.

And our cars have all this expensive pollution reduction equipment, and it sits unused for more than 23 hours of the day most days! Kind of a waste. But when a car is shared, the payback and incentive to improve mpg and emissions is leveraged. Things that don't make sense, or are marginal become very sensible for a high mileage vehicle.

-ERD50

 

[Eyesman]

Consider that we are in the midst of a huge disruption which could be a perfect storm of rapid change in the next decade or so. With the combination of cheaper batteries, electric vehicles, cloud computing and ride sharing, autonomous driving, cheaper solar energy with battery storage, the current models as we know it could be drastically altered.

Check out this video of a talk by Tony Seba. It is an eye opener. It is a fairly long video, but he makes some compelling arguments. I believe it will be worth your time to watch it.

https://youtu.be/2b3ttqYDwF0

 

[REWahoo]

So this Seba guy...

... argues that the Electric Vehicle, battery storage, and solar power, along with autonomous vehicles, are a perfect example of a 10x exponential process which will wipe fossil fuels off the market in about a decade.

Really?

 

[ERD50]

Consider that we are in the midst of a huge disruption which could be a perfect storm of rapid change in the next decade or so. With the combination of cheaper batteries, electric vehicles, cloud computing and ride sharing, autonomous driving, cheaper solar energy with battery storage, the current models as we know it could be drastically altered.

Check out this video of a talk by Tony Seba. It is an eye opener. It is a fairly long video, but he makes some compelling arguments. I believe it will be worth your time to watch it.

https://youtu.be/2b3ttqYDwF0

So this Seba guy...

... argues that the Electric Vehicle, battery storage, and solar power, along with autonomous vehicles, are a perfect example of a 10x exponential process which will wipe fossil fuels off the market in about a decade.

Really?

Thanks REWahoo. Based on that, I won't waste 1 second watching that long video. We don't need hyperbole, we need solutions!

None of those things are moving exponentially (autonomous vehicles might be the closest). Wow, batteries getting 2x better each year? Solar is gettin 2x better each year? - not even Moore's Law was that aggressive (2x the transistor density in 18 months). And Moore himself said it didn't apply to most other areas.

Advances in these areas are pretty well understood. Solar is getting better, it's on a curve. But installation costs are flat, maybe increasing. Batteries are on a curve (~ 7%/year, IIRC). That's all good. It's not disruptive, and not in a decade.

-ERD50

 

[NW-Bound]

The problem with renewable energy is no longer about producing it. It's about storing it for days when it's cloudy and the wind does not blow.

People keep talking about hydro storage, but they don't know how large a lake would be needed to store what the US is using in a day.

And lithium battery is cool (I like it a lot), but do people know what it would cost to store just 1 day of use for a typical household? Out of curiosity, I compute what it would cost for mine, and it's not pretty.

 

[samclem]

People keep talking about hydro storage, but they don't know how large a lake would be needed to store what the US is using in a day.

Storage is tough. If electricity gets more expensive >and< if smart metering takes off, there will be some movement at the margins for storage at the point of use. It could be batteries (in EV cars or a "battery wall", but those standalone batteries hardly make sense for most users now). Heat and AC is a fairly big part of residential energy use, and there are some fairly simple ways to store heat and "cool" for use within a day or so. So, if you could buy electricity for 50% off the standard rate and had a smart system that could get good at estimating when it would be smart to cool or heat that 5000 gallons of water buried in the insulated tank in the back yard, it would be worth it. Ironically, it would also drive up overall electrical use (the heat and cool in storage does leak).

 

[NW-Bound]

In the energy crisis of the 70s, there were many people experimenting with using water tanks for thermal storage inside the home. No problem with energy leak here, as the tanks are inside the home and you do not want to insulate them anyway for passive heat transfer.

Have not seen much about this lately. If I were to build my own home, would not mind experimenting with this. Large columns of stainless steel tanks in the middle of the home, anyone?

It would be cool to "arbitrage" the different rates I am paying. It's 22c/kWh in the peak period of 1PM-8PM, and 8c/kWh outside that. A huge difference.

Thought about using lithium battery to do the storage for "arbitraging", but I would need one the size of what is inside the Tesla P100D, and people know how expensive that is.

 

[samclem]

Have not seen much about this lately. If I were to build my own home, would not mind experimenting with this. Large columns of stainless steel tanks in the middle of the home, anyone?

It could work well for heating, but making the house comfortable in summer is more trouble, unless the climate is very dry. The storage medium has to be quite cool to wring enough moisture from the air to get the humidity down. Making the indoor air cool isn't hard, but 72 deg and 100% humidity isn't comfortable.

 

[NW-Bound]

OK. I overlook that humidity factor, but we never have that problem in the SW. Never! So, forgive me for overlooking that.

We are getting away from the ICE discussion, but as I said earlier about producing power being no longer a problem, let me mention something here to substantiate that.

Using real-life data from NREL, I made a spreadsheet of how much power would be produced by 1kW worth of panel in each of the months in the year. Then, I multiplied the kWh in each month by the varying rate that my utility charges during that month. The result is that 1 kW of panel will produce $304 worth of electricity annually. It would be more in places like California where they gouge people.

Now, the above number does not include efficiency, and the biggest one is caused by the panels not operating at the optimal condition (STC vs. NOTC). The number could be derated to 75%, but the above number gives you a ball park figure.

Now, how much is the cost of 1kW worth of panel? It's a stinkin' $400 at a solar store near me.

Where am I going with this? I am looking to build a DIY off-grid system myself. The goal is not to be energy independent (storage cost again), but to reduce the power bill, particularly in the summer.

PS. The above dollar amount assumes the panels are tilted south with an angle equal to the latitude. As I will be mounting them flat on a pergola (not on my tile roof), I will get only 90%. The loss is low because while the kWh loss factor is high in the winter for flat-mounted panels, flat-mounting is best in the summer where the electricity cost is the highest. Yes, my spreadsheet addresses that mounting factor too.

PPS. I am adding to the spreadsheet the cost to build the pergola, and all equipment costs. Cannot do anything yet, as it is hot as Hades out there, but I will break ground in the winter. Yep. I am going for this.

 

[flintnational]

We should remain technology agnostic, and let the best solution prevail, regardless if it is old (like the wheel!), or 'modern'.

-ERD50

+1

Well stated.

FN

 

[Music Lover]

And our cars have all this expensive pollution reduction equipment, and it sits unused for more than 23 hours of the day most days! Kind of a waste. But when a car is shared, the payback and incentive to improve mpg and emissions is leveraged. Things that don't make sense, or are marginal become very sensible for a high mileage vehicle.

-ERD50

While most people may only need a car for 1 or 2 hours a day, a lot of them need it for the same 1 or 2 hours. Therefore, you need enough cars to cover peak use or else people are waiting a long time when it's busy. And, where are all the extra cars stored in off peak hours?

Another issue is that car sharing means that it will almost always mean more miles travelled per trip. If I drive from home to my destination, and then from my destination back home, the car travels less miles than if a car first has to drive to pick me up, and then has to pick me up again from wherever it was to take me home. That's both added miles and added congestion on the road.

 

[ERD50]

While most people may only need a car for 1 or 2 hours a day, a lot of them need it for the same 1 or 2 hours. Therefore, you need enough cars to cover peak use or else people are waiting a long time when it's busy. And, where are all the extra cars stored in off peak hours?

Another issue is that car sharing means that it will almost always mean more miles travelled per trip. If I drive from home to my destination, and then from my destination back home, the car travels less miles than if a car first has to drive to pick me up, and then has to pick me up again from wherever it was to take me home. That's both added miles and added congestion on the road.

Yes, sharing has limits, like anything else. But with modern technology, it can do at least a bit more than it used to do. There was an article a while ago, about how Walmart was offering (key word 'offering' - I don't want to get off-topic on that) employees a chance to make a few extra bucks by delivering packages from the store to individuals on their way home. So a smart algorithm can make use of our regular commutes.

I've envisioned a kind of way-out scenario where some sort of lock-box is mounted on lots of cars, and an algorithm gets packages routed from a warehouse to a home, just riding on the backs of cars along the way. Maybe a delivery truck would get packages from the warehouse, and 'seed' them to kiosks along major roads, and then cars would be notified that there is a package to pick up, and they just pull over and get loaded by this kiosk, by a robotic arm that could auto-unlock the box on the car. They drive away, and they are told which kiosk to stop by next, to have it transferred for the next leg of the journey (or to the final address). No individual driver would go very far out of their way at all, it would all be mapped to the regular routes that they told the system they would be on that day, and how far out of their way they would accommodate that day, and it could all be very automatic. I guess that's a little like how Internet packets work? A little?

But as far as the expensive pollution equipment, and expensive tech for more mpg, it just seems that would all be better used on taxis and buses. It seems that now, most/all of the Chicago taxis are hybrids, and the buses are switching over. But it seems crazy that they were not the first to adopt the tech. Makes a lot less sense to put that battery in a car that drives 1-2 hours a day, versus 12 or more hours a day.

But that gets into subsidies, and warped incentives, and probably best to not go there...

-ERD50