SomptingGuy
Automotive
See title. An open question to all. What will we be driving in 10 years time? (I'll have added another 20k to my '87 Volvo, but that's another matter).
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Gas/Hybrid, Diesel, Diesel/Hybrid, Fuel Cell - where will it end? 13
- Thread starter SomptingGuy
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ASEI
Aerospace
- Jul 8, 2008
- 7
PS - my prediction is that we'll mine harder and harder oil deposits than middle eastern light crude oil (the current proven reserves) (shale oil ect) and thus extend the gasoline supply out 100 years or so more than is currently predicted.
After that, it depends on the politics and science of the situation 100 years from now. We could be gassifying coal using nuclear driven processes. We could have some sort of battery with high enough energy density by then. We could put the nuclear reactors (beta-voltaic batteries? super RTGs?) directly on the vehicles.
After that, it depends on the politics and science of the situation 100 years from now. We could be gassifying coal using nuclear driven processes. We could have some sort of battery with high enough energy density by then. We could put the nuclear reactors (beta-voltaic batteries? super RTGs?) directly on the vehicles.
BigUglyFord
Automotive
ASEI has an excellent point! And let me expand on it, until we find a way to power our cargo-ships, trains and heavy-duty trucks we will be dependant on fossil fuels. My earlier post was mainly concerned with passenger vehicles & light duty trucks, as this is what I teach. Getting the light vehicles to alternatives will greatly improve our situation and leave more reserves for the shipping industries. I was reviewing a NOVA DVD for my class on solar energy in which they say a hundred mile square solar array in a dessert state(Arizona) could power the whole US. I also remember seeing something on the use of supper conductors and liquid nitrogen to transmit power with very little loss.
Play with the idea that every car would be electrically driven. If we would generate all this energy with fossil fueled power plants, would we still be consuming less oil than burning it in the engine of the car? As I see it we don´t have to distribute the petrol by trucks. We also can get higher efficieny in a power plant. We loose perhaps 2% distributing the electricity and another 5-10% in the car.
The only problem then is the power grid in US. That is not an issue in many other countries though.
In 3, not 10, years time we will have full hybrid cars with small ( 1 liter?) turbo chared engines generating electricity if needed.
The only problem then is the power grid in US. That is not an issue in many other countries though.
In 3, not 10, years time we will have full hybrid cars with small ( 1 liter?) turbo chared engines generating electricity if needed.
BigUglyFord
Automotive
We would use alot less.. The internal combustion engine we are adicted to is only 30% efficient which in my opinion is a gross waste.
rnordquest
New member
ASEI, you'd only need 100,000 sq mi of concentrated solar to generate the power you need. That's not even a major portion of TX. I'm not talking PV panels. The efficiency of collecting heat is much higher than PV panels right now and it's easier to store heat through the night than electricity. They have power plants like this already in operation so it's nothing new.
globi5
Mechanical
- Oct 10, 2005
- 281
It's doubtful that nuclear will ever provide as much as electricity as renewables do. More hydro than nuclear power is already generated anyway. Wind capacity is currently growing about 20 times faster than nuclear.
Wind is less costly than new nuclear:
This report funded by the nuclear industry states that new nuclear power production costs are between: 8.3 and 11.1 cents/kWh
However this report assumed capital overnight costs of only $2950/kW and new nuclear power plants to be built in Florida already assumed capital costs of over $7000/kW.
According to the Department of Energy the costs of wind power are between 3 and 6.4 cents per kWh. Average capital costs of Windturbines are $1480/kW (2006).
South dakota alone has enough wind to power half the US:
And interconnected Windfarms can provide baseload:
Thinfilm photovoltaics is claimed to reach costs of below $1000/kW by 2010.
120,000 km2 of the US is built. If only 10% of that area has roof area, that leads to a maximum solar flux of 12,000 GW or 1,200 GW max photovoltaic power at only 10% efficiency.
92 sq mi x 92 sq mi (or about 8% of Nevada and less than 10,000 sq mi) is enough to power the entire US with solar thermal.
HVDC can transmit power from coast to coast with losses of only 3% per 1000 km at costs of €70/kW per 1000 km (transmission line only).
Aircrafts, trucks and commercial ships will probably still be oil powered in the far future, but there's no reason to keep on powering heating systems and private transportation on oil.
Btw, China has significantly more solar hot water capacity installed than nuclear power:
Wind is less costly than new nuclear:
This report funded by the nuclear industry states that new nuclear power production costs are between: 8.3 and 11.1 cents/kWh
However this report assumed capital overnight costs of only $2950/kW and new nuclear power plants to be built in Florida already assumed capital costs of over $7000/kW.
According to the Department of Energy the costs of wind power are between 3 and 6.4 cents per kWh. Average capital costs of Windturbines are $1480/kW (2006).
South dakota alone has enough wind to power half the US:
And interconnected Windfarms can provide baseload:
Thinfilm photovoltaics is claimed to reach costs of below $1000/kW by 2010.
120,000 km2 of the US is built. If only 10% of that area has roof area, that leads to a maximum solar flux of 12,000 GW or 1,200 GW max photovoltaic power at only 10% efficiency.
92 sq mi x 92 sq mi (or about 8% of Nevada and less than 10,000 sq mi) is enough to power the entire US with solar thermal.
HVDC can transmit power from coast to coast with losses of only 3% per 1000 km at costs of €70/kW per 1000 km (transmission line only).
Aircrafts, trucks and commercial ships will probably still be oil powered in the far future, but there's no reason to keep on powering heating systems and private transportation on oil.
Btw, China has significantly more solar hot water capacity installed than nuclear power:
ASEI
Aerospace
- Jul 8, 2008
- 7
"The internal combustion engine we are adicted to is only 30% efficient which in my opinion is a gross waste. "
Actually, though I don't have the reference, I believe my old thermodynamics textbooks had the maximum possible efficiency for a compression driven (diesel) IC engine at about 80%. Large generators approached 70% in practice, and smaller vehicles weren't really all that far behind them.
The gains that you can make with efficiency improvements aren't all that large, and you can't beat Carnot efficiency for a heat engine no matter how it's constructed.
Actually, though I don't have the reference, I believe my old thermodynamics textbooks had the maximum possible efficiency for a compression driven (diesel) IC engine at about 80%. Large generators approached 70% in practice, and smaller vehicles weren't really all that far behind them.
The gains that you can make with efficiency improvements aren't all that large, and you can't beat Carnot efficiency for a heat engine no matter how it's constructed.
TDIMeister
Automotive
Ideal air standard cycle efficiencies of very conventional ICEs can reach 60-70+ percent, and this is likely the figure that peddlers of newfangled engines quote half-truthfully, thinking that the people who matter (investors for money and the public for mindshare) are ignorant enough to buy it (and it appears to work often enough).
However, the air standard efficiency is NEVER reached in a real engine, nor even closely approached. Inventors that devise new engine ideas that still run on some variant of established thermodynamic cycles think they can return to or exceed the ideal efficiencies, but they're flat wrong. For automotive Diesel engines, a best point of 43% BTE has been reached in production. For large engines, it can be appreciably higher, culminating in 55+ percent for marine engines. Research has been taking place to bring efficiencies in on-highway trucks to 60% BTE by carefully identifying and addressing all sources of losses, and employing some sort of exhaust energy recovery system like turbocompounding, a bottoming cycle or thermionic converters.
In contrast, many like to malign the "wastefulness" of ICEs, and wax lyrical about fuel cells and EVs. Well, in a PEM fuel cell, the ideal open-circuit cell efficiency can be over 90%, but again, this is NEVER attained nor approached by a long shot. After accounting for all the sources of losses, the electrical output of the fuel cell stack yields an efficiency of about 50%; values as high as 65% have been attained in labs and is dependent on conditions, but this is not the end of losses. Some power is use to drive an air blower or compressor that is used in a PEM-FC to increase the power density, then there losses in the power electronics and electric motors (the latter between 80-90% efficient over a wide operating range). These losses are fairly fixed, and at very low demanded load, the system efficiency is accordingly very low to offset these parasitic losses, even though a FC is theoretically most efficient at low current loads. All this doesn't even consider the energy conversion efficiencies of the hydrogen fuel from a primary energy source that fuel cells need (either generated somewhere or reformed onboard).
Ditto EVs. Many people claim efficiencies of 80-90%, but consider only the losses at the electric motor. There are also losses through the power electronics (~90% efficient), as well as charge- and discharge losses (~80% each, mostly depending on battery type). Considering only these losses, the system efficiency drops down to something more like 45-55%. Hmmm... not so far off from the best ICEs. Again, the primary energy source has to some from somewhere. If it's generated from an ICE acting as a range extender, then your limiting factor is actually the efficiency of the ICE(!); if the electrical power comes from the grid, the efficiency depends on the mix of generating sources, but an efficiency figure of 40%-50% is typical for a wide range thermal power plants that include steam- and gas turbines using coal, oil, natural gas or nuclear as the primary energy source.
So let's recap. We've seen that regardless of the technology used, we come to a total efficiency wherein still a big chunk if not a majority of available energy is actually lost. Nobody has credibly come up with (nor probably will in my lifetime), any solution so revolutionary that will raise total, real-world efficiencies far above where they are today. And that's not the problem: as "wasteful" as all these current solutions are, the bigger problem is that transport applications are rarely operating anywhere near the potential best efficiency points of ANY of the abovementioned solutions. Regardless of ICE, FC or EVs, if these "wasteful" devices could only operate close to their (still terrible) peak efficiency most of the time, the real-world fuel consumption -- and your fuel bill -- could be reduced by as much as half. And the thing is, there is ABSOLUTELY no magic in it.
That's what hybrids are trying to do: trying to get the wasteful ICE to operate more frequently at operating points that are more efficient, and less or not all all when it isn't. It really is all it comes down to.
However, the air standard efficiency is NEVER reached in a real engine, nor even closely approached. Inventors that devise new engine ideas that still run on some variant of established thermodynamic cycles think they can return to or exceed the ideal efficiencies, but they're flat wrong. For automotive Diesel engines, a best point of 43% BTE has been reached in production. For large engines, it can be appreciably higher, culminating in 55+ percent for marine engines. Research has been taking place to bring efficiencies in on-highway trucks to 60% BTE by carefully identifying and addressing all sources of losses, and employing some sort of exhaust energy recovery system like turbocompounding, a bottoming cycle or thermionic converters.
In contrast, many like to malign the "wastefulness" of ICEs, and wax lyrical about fuel cells and EVs. Well, in a PEM fuel cell, the ideal open-circuit cell efficiency can be over 90%, but again, this is NEVER attained nor approached by a long shot. After accounting for all the sources of losses, the electrical output of the fuel cell stack yields an efficiency of about 50%; values as high as 65% have been attained in labs and is dependent on conditions, but this is not the end of losses. Some power is use to drive an air blower or compressor that is used in a PEM-FC to increase the power density, then there losses in the power electronics and electric motors (the latter between 80-90% efficient over a wide operating range). These losses are fairly fixed, and at very low demanded load, the system efficiency is accordingly very low to offset these parasitic losses, even though a FC is theoretically most efficient at low current loads. All this doesn't even consider the energy conversion efficiencies of the hydrogen fuel from a primary energy source that fuel cells need (either generated somewhere or reformed onboard).
Ditto EVs. Many people claim efficiencies of 80-90%, but consider only the losses at the electric motor. There are also losses through the power electronics (~90% efficient), as well as charge- and discharge losses (~80% each, mostly depending on battery type). Considering only these losses, the system efficiency drops down to something more like 45-55%. Hmmm... not so far off from the best ICEs. Again, the primary energy source has to some from somewhere. If it's generated from an ICE acting as a range extender, then your limiting factor is actually the efficiency of the ICE(!); if the electrical power comes from the grid, the efficiency depends on the mix of generating sources, but an efficiency figure of 40%-50% is typical for a wide range thermal power plants that include steam- and gas turbines using coal, oil, natural gas or nuclear as the primary energy source.
So let's recap. We've seen that regardless of the technology used, we come to a total efficiency wherein still a big chunk if not a majority of available energy is actually lost. Nobody has credibly come up with (nor probably will in my lifetime), any solution so revolutionary that will raise total, real-world efficiencies far above where they are today. And that's not the problem: as "wasteful" as all these current solutions are, the bigger problem is that transport applications are rarely operating anywhere near the potential best efficiency points of ANY of the abovementioned solutions. Regardless of ICE, FC or EVs, if these "wasteful" devices could only operate close to their (still terrible) peak efficiency most of the time, the real-world fuel consumption -- and your fuel bill -- could be reduced by as much as half. And the thing is, there is ABSOLUTELY no magic in it.
That's what hybrids are trying to do: trying to get the wasteful ICE to operate more frequently at operating points that are more efficient, and less or not all all when it isn't. It really is all it comes down to.
globi5
Mechanical
- Oct 10, 2005
- 281
This EV car requires 11 kWh / 100 km 1 liter of gasoline corresponds to 9 kWh. Therefore 1.2 liter / 100 km, which is already pretty impressive.
However and more importantly: Assuming one has a parking spot with a roof (2.5m * 7m and a 30 degree incline = 20 m2) and covers them with PV cells.
With a PV efficiency of only 10% and 1500 hours sun hours per year one ends up with 3,000 kWh per year.
3,000 kWh is enough to drive 27,000 km.
No one will ever be able to grow enough biofuel-plants in a little backyard to power an ICE engine of a small car and cover a distance of 27,000 km with it.
PS: One single 3MW wind turbine requiring a foot print of 20m2 and 2,500 hours of wind per year produces 7,500,000 kWh. Enough energy to do the same as mentioned above but with 2,500 cars.
However and more importantly: Assuming one has a parking spot with a roof (2.5m * 7m and a 30 degree incline = 20 m2) and covers them with PV cells.
With a PV efficiency of only 10% and 1500 hours sun hours per year one ends up with 3,000 kWh per year.
3,000 kWh is enough to drive 27,000 km.
No one will ever be able to grow enough biofuel-plants in a little backyard to power an ICE engine of a small car and cover a distance of 27,000 km with it.
PS: One single 3MW wind turbine requiring a foot print of 20m2 and 2,500 hours of wind per year produces 7,500,000 kWh. Enough energy to do the same as mentioned above but with 2,500 cars.
TDIMeister
Automotive
I agree that widespread deployment of renewable energy (solar, wind, etc.) is the only way to make a significant dent on fossil primary energy consumption, but the absolute quantity of energy consumed will not be significantly improved considering the relatively low conversion efficiencies in the current immature state of development. The number one concern is somehow bringing prices of alternative energy closer to parity with fossil energy, and this is a huge challenge.
In the case of photovoltaics, kWh/$ (unsubsidized) and W(e)/m^2 need to be significantly improved from the current status. In the case of wind turbines and other alternatives, the NIMBY movement needs to be pacified.
In the case of photovoltaics, kWh/$ (unsubsidized) and W(e)/m^2 need to be significantly improved from the current status. In the case of wind turbines and other alternatives, the NIMBY movement needs to be pacified.
globi5
Mechanical
- Oct 10, 2005
- 281
True photovoltaics will need to be cheaper per kWh.
But as soon as thinfilm PV factories in the GW range will be online, prices will drop.
At this point photovoltaics can already compete with electricity produced from a diesel engine.
W per m2 is really not that crucial for most applications. A PV efficiency of 10% is sufficient to power an EV with the parking spot area available. Even 5% PV efficiency is sufficient to cover the electricity needs of a one family house with the roof area available. More important are costs per Watt of PV.
In addition cooling and heating needs should mostly be covered with solar hot water capacity, rather than photovoltaics which already has an efficiency of over 80%.
But as soon as thinfilm PV factories in the GW range will be online, prices will drop.
At this point photovoltaics can already compete with electricity produced from a diesel engine.
W per m2 is really not that crucial for most applications. A PV efficiency of 10% is sufficient to power an EV with the parking spot area available. Even 5% PV efficiency is sufficient to cover the electricity needs of a one family house with the roof area available. More important are costs per Watt of PV.
In addition cooling and heating needs should mostly be covered with solar hot water capacity, rather than photovoltaics which already has an efficiency of over 80%.
ASEI makes a good point about commercial vehicles. If you buy many of your staples (food, clothing and shelter) from a store these goods must be transported by truck, train or ship. Trucks, ships, and the off highway equipment that grows the food and builds the roads will never run off the grid, so some form of chemical fuel will be required. I think internal combustion engines can be more thermally efficient if there is no crank shaft and operated as a 4 stroke with the power stroke being longer than the intake and compression strokes. One difficulty in accomplishing this is having a hydraulic or electric storage system to take the place of the flywheel.
TDIMeister makes good points about vehicle efficiency. All vehicles are far less thermally efficient then the laboratory efficiency numbers published. To my knowledge no one has actually bothered to do this type of testing. I built a pair if wheel torque sensors to install on a garbage truck to determine the energy used for acceleration, what is available for recuperation and what the actual thermal efficiency is. So far no one is interested in allowing me to collect the data. One company is concerned about being sued by the vehicle or engine manufacture, another does not want the competitor to know the results.
In 10 to 20 years the throttle will not control any engine functions, there will be all wheel regenerative braking and chemical fuel delivering your products to the store. As to personal transportation, it will depend on what energy form each government chooses to support with tax incentives and, or subsidies, or penalize with taxes, and, or hamper infrastructure construction.
My suggestion is to not allow governments to choose one preferred energy solution, but nurture all. The most efficient and lowest cost will become obvious after a few years.
Ed Danzer
TDIMeister makes good points about vehicle efficiency. All vehicles are far less thermally efficient then the laboratory efficiency numbers published. To my knowledge no one has actually bothered to do this type of testing. I built a pair if wheel torque sensors to install on a garbage truck to determine the energy used for acceleration, what is available for recuperation and what the actual thermal efficiency is. So far no one is interested in allowing me to collect the data. One company is concerned about being sued by the vehicle or engine manufacture, another does not want the competitor to know the results.
In 10 to 20 years the throttle will not control any engine functions, there will be all wheel regenerative braking and chemical fuel delivering your products to the store. As to personal transportation, it will depend on what energy form each government chooses to support with tax incentives and, or subsidies, or penalize with taxes, and, or hamper infrastructure construction.
My suggestion is to not allow governments to choose one preferred energy solution, but nurture all. The most efficient and lowest cost will become obvious after a few years.
Ed Danzer
TDIMeister
Automotive
IMO there's absolutely nothing wrong with having a crankshaft as opposed to some other mechanism of translating the reciprocating motion into rotation. It's been tested for over a hundred years, and even more if you include predecessors of the ICE long before that. It's still here today because it works and works well. Some people point out the "wasteful" kinematics and poor mechanical efficiency of a slider-crank mechanism. I remember a while ago a thread in this forum going around in circles talking about lever arm effectiveness and so on -- a bunk argument. The cyclical integral of the PdV diagram MUST and WILL equal the work at the flywheel, minus parasitic losses and fricton. And to friction, a more rigorous analysis will show that the majority of the friction losses occur in the piston group and the remainder in the con rod big-end and main bearings. "Lever arm effectiveness" doesn't play ANY role in this because of the statement above regarding work equality that MUST obey the First Law of Thermodynamics!!
Moving on... where an alternative mechanism IS indeed advantageous is where it can realise an Atkinson/Miller cycle, and permit adjustable compression ratios, all the while being low in friction and mass. However, I am personally not a fan of VCR concepts that vary the CR with the effect of altering the clearance- or squish volume. IMHO a small range of CR adjustability can be equally effectively controlled by altering valve timing, which can be implemented cheaper than some newfangled mechanism.
Going back to the original topic of the thread, I see ICEs continuing to kick 20 years from now. They will be greatly downsized from today; majority forced-induction and very sophisticated electrification and electronic control of subsystems (e.g. valvetrain) filtering down from expensive engines to the entry-level; direct-injected with a limited HCCI operating mode at low- and moderate loads; little distinction from today's Diesel and Otto engines; hybridized in different degrees; and exhaust aftertreatment becoming one of the most complex and expensive subsystems in the entire engine.
Moving on... where an alternative mechanism IS indeed advantageous is where it can realise an Atkinson/Miller cycle, and permit adjustable compression ratios, all the while being low in friction and mass. However, I am personally not a fan of VCR concepts that vary the CR with the effect of altering the clearance- or squish volume. IMHO a small range of CR adjustability can be equally effectively controlled by altering valve timing, which can be implemented cheaper than some newfangled mechanism.
Going back to the original topic of the thread, I see ICEs continuing to kick 20 years from now. They will be greatly downsized from today; majority forced-induction and very sophisticated electrification and electronic control of subsystems (e.g. valvetrain) filtering down from expensive engines to the entry-level; direct-injected with a limited HCCI operating mode at low- and moderate loads; little distinction from today's Diesel and Otto engines; hybridized in different degrees; and exhaust aftertreatment becoming one of the most complex and expensive subsystems in the entire engine.
The problem with a crankshaft engine for most applications is they are multi-cylinder. During a drive cycle, the power requirement is different than the optimum multi-cylinder engine output. Storing more than a few seconds worth of energy in batteries, capacitors, or hydraulic accumulators is a waste of energy. A single cylinder linear engine that only outputs electrical energy or hydraulic energy that is decoupled from the wheels should be the most energy efficient to propel on highway or off-highway vehicles.
Ed Danzer
Ed Danzer
ASEI
Aerospace
- Jul 8, 2008
- 7
One of the points I was trying to make about efficiency was that it was a diminishing return game. Even if you did invest in pulling the absolute Carnot-hugging efficient engine out of the hat, you really only reduce consumption rates (and by less than half at most). You can't become more and more efficient until you don't need any energy.
I think focusing on producing more energy per-capita by whatever method is going to be more productive in the long run.
In the end, I'd like to see a state where energy is produced in sufficient abundance that everyone can enjoy a 1st world style of life. Not one where we are pushed into more and more limited lifestyles in the name of "efficiency".
I think focusing on producing more energy per-capita by whatever method is going to be more productive in the long run.
In the end, I'd like to see a state where energy is produced in sufficient abundance that everyone can enjoy a 1st world style of life. Not one where we are pushed into more and more limited lifestyles in the name of "efficiency".
Eventually, soccer moms will just have to realize there is life after 2 ton metric SUVs with v8 and v10 gassers and start flirting with 1.0~1.6 litre turbodiesel engines on 800~1700 kg fwd cars. If only gas and diesel cost as much in the US as it does here so they'd have something to really whine about.
After that, much of the same. Just on diesel from coal for awhile.
After that, much of the same. Just on diesel from coal for awhile.
IMO, diesel/electric hydbrid, is the way to go. BUT!, diesel is being given short shrift by market manipulation of diesel prices. I can find no good reason that diesel is $1.00/gal more than 89 Oct. Gasoline. Oh, we have to take the sulphur out now. Well, we have to take the sulphur out of gasoline also.
Diesel/electric worked for submarines WWI and WWII. Works for railroads today. U.S. Military runs everything now on JP-8, jets to generators. Stochiometric efficiencies of diesel are approaching what? 40%.
Diesel/electric worked for submarines WWI and WWII. Works for railroads today. U.S. Military runs everything now on JP-8, jets to generators. Stochiometric efficiencies of diesel are approaching what? 40%.
Diesel is higher than gasoline because the demand for diesel is inflexible relative to gasoline. A higher percentage of gasoline usage is "voluntary" relative to diesel. Diesel in general has a less volatile price than gasoline because demand is unable to respond to market changes and swing the price quickly. Diesel is not always higher, historically it has often been lower.
Much of the price in fuel these days is due to the heroic logistics required to make sure everybody has some, including that enough crude gets refined to the right products in the right places. Therefore, actual production costs of low-sulfur diesel are only poorly related to what is happening in the market.
Much of the price in fuel these days is due to the heroic logistics required to make sure everybody has some, including that enough crude gets refined to the right products in the right places. Therefore, actual production costs of low-sulfur diesel are only poorly related to what is happening in the market.
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