Acutally, that is a typo. Im talking about converting all 220 million automobiles currently driven in the US. The energy equivlant from a powerplant production standpoint is 57 GW.
I'm intrigued. How did you come up with the energy equivalent of 57GW? Does the 220 Million figure includes all cars and trucks including tractor trailers?
So less energy is required to run the fleet of automobiles traveling throughout the country than is required to run our air conditioning? Not that I don't believe you, but I'm, well, a bit stunned by that figure. I have zero figures for this, but it just seems that driving a 2-ton vehicle should use more energy than running an a/c unit. No?
I wouldn't be so sure about that. A/C is a hellaciously wasteful powerhog. Cars have a few things going for them, first of all the fact that they roll on wheels. A lot of people have surely rode a bike before at some time. I'm sure you know from riding a bike that oftentimes you don't even need to peddle. If you are going down even a slight incline you can pick up a lot of speed and just roll with no effort.
The truth is this applies to cars too, and actually you can roll quite fast on even a very slight incline as a result of the car's weight. I think many people are under the assumption that without the engine pushing constantly the car would just stop, but that is not true (if you have a manual it's easy to push the clutch in, it can be impressive sometimes just how far you can roll with no power input whatsoever).
Once a car is actually rolling it doesn't necessarily require that much power to keep it in motion, especially with low rolling resistance tires. On the other hand with AC we have the issue that people are trying to keep their houses well below the ambient outdoor temperatures. When you're trying to keep your house 20-25 degrees below the ambient outdoor temperature you are just going to waste tons and tons of energy. It's kind of like running uphill, you are spending a lot of energy fighting the laws of nature. An AC will be running basically nonstop during the day, whereas on average a car will not be in motion more than a small fraction of the day.
Just to clarify, I am not saying that Hrothgar is necessarily correct. I'm just pointing out how it might not be that surprising if vehicle power usage was not that much different from AC power usage.
The USA currently uses about 320 million gallons of gasoline in a day. A gallon of gasoline yields around 36.6 KWH, so the heat energy in the gasoline used in one day in the USA is about 12,000 GWH.
According to a Wikipedia article, electric vehicles are about 4 times as energy efficient as gasoline vehicles. If all the cars burning all that gasoline were converted to elctric drive, the efficiency gain would require 3,000 GWH per day. If all vehicles were recharged in a 12-hour off period, this would require an average capacity of 250 GW, or about 25% of the nominal grid capacity.
Current battery recharging and discharging technology is well, technologically backwards. When you recharge a battery, only a fraction of the energy used actually gets stored in the battery. The rest is lost to heat. Dont believe me? Go and recharge your cell phone and then pick it up and feel how 'warm' the back side of it is, where the battery is located. Also, take a look at most laptop batteries and how hot they get. The heat produced by the computer doesnt cause all the heat to be localized in one location...
The Tesla itself takes only 3 hours to go from completely drained to a full charge. Far less then the 12 hour time period you expect the plugged in cars to drain energy from the grid.
The new batteries such as the one Toshiba developed take a fraction of the time current batteries take to recharge. These new batteries have the potential to be ~80% recharged in ONE MINUTE. Think about that for a second before you dismiss PEVs outright.
The ICE you are probably currently driving around only has an efficiency of less then 18%. That means for the 134,000 btu of energy stored in each gallon of gasoline, your only using at most 24,120 btus to move your car. The rest is lost to heat. To prove this to yourself, go and drive about 150 miles, then park and have a seat on your supposedly nice and cool engine cover.
Electric cars are VASTLY more efficent and using energy then ICEs are. And the ironic thing about EVs, the more powerful the electric motor is, the more efficient it becomes. Thats why vehicles like the Tesla have a 185 hp electric motor when many people point out that you really only need about 50hp to get the job done. It's all about efficiency.
Obviously, any massive EV scale up would require the usage of 'smart' recharging appliances. These appliances would be able to determine weather or not the energy grid is 'spikeing' due to excessive power drainage, or if energy usage is low and it is safe to recharge the batteries.
The Tesla and the upcoming 4 door sedan are stated to have a range of about 250 miles per charge. The nationwide AVERAGE miles per day per vehicle is about 30 miles. That means that on average, you will drive around 30 miles a day to do all your shopping, getting to and from work and any other trips you make. That means you technically only need to recharge ~once every 8 days. Lets just place that figure on a nice 1 day a week recharge period for the AVERAGE driver.
----
Now what does this all mean? It wont take 257 GHw of electricity every night to recharge the vehicle, it will take ~37 ghw a night, asuming INTELLIGENT recharging with intelligent applications by the consumers. Comments?
Current battery recharging and discharging technology is well, technologically backwards. When you recharge a battery, only a fraction of the energy used actually gets stored in the battery. The rest is lost to heat. Dont believe me? Go and recharge your cell phone and then pick it up and feel how 'warm' the back side of it is, where the battery is located. Also, take a look at most laptop batteries and how hot they get. The heat produced by the computer doesnt cause all the heat to be localized in one location...
So that means you will need more energy in total than just the amount expended in motion. That doesn't help your case.
The Tesla itself takes only 3 hours to go from completely drained to a full charge. Far less then the 12 hour time period you expect the plugged in cars to drain energy from the grid.
Charging time doesn't matter. What matters is the amount of energy drawn from the grid. Shorter time = higher current. The energy requirement remains the same.
The new batteries such as the one Toshiba developed take a fraction of the time current batteries take to recharge. These new batteries have the potential to be ~80% recharged in ONE MINUTE. Think about that for a second before you dismiss PEVs outright.
Again, charge time isn't the issue. A shorter charge time may make it easier for power companies to regulate the smart chargers and prevent grid overload, but it doesn't change the amount of power they will need to provide.
The ICE you are probably currently driving around only has an efficiency of less then 18%. That means for the 134,000 btu of energy stored in each gallon of gasoline, your only using at most 24,120 btus to move your car. The rest is lost to heat. To prove this to yourself, go and drive about 150 miles, then park and have a seat on your supposedly nice and cool engine cover.
As I said above, the efficiency advantage of electrics over fossil fuelled ICE is well known. The advantage is given as 4:1 by this Wikipedia article. That was factored into my analysis above.
Obviously, any massive EV scale up would require the usage of 'smart' recharging appliances. These appliances would be able to determine weather or not the energy grid is 'spikeing' due to excessive power drainage, or if energy usage is low and it is safe to recharge the batteries.
This is a given for preventing grid overload. It doesn't address the total amount of energy needed.
The Tesla and the upcoming 4 door sedan are stated to have a range of about 250 miles per charge. The nationwide AVERAGE miles per day per vehicle is about 30 miles. That means that on average, you will drive around 30 miles a day to do all your shopping, getting to and from work and any other trips you make. That means you technically only need to recharge ~once every 8 days. Lets just place that figure on a nice 1 day a week recharge period for the AVERAGE driver.
If you maintain the passenger-miles currently driven and just change the energy source, you wind up with the numbers I calculated above. Here you are moving the goalposts by assuming a change in driving habits.
My analysis stands - 250 GW supplied for 12 hours per day is required to replace the transportation capability provided by gasoline engines today. You can cut that energy requirement by changing people's driving habits, but to get it to 57 GW (I assume 37 was a typo?) you'd have to cut the passenger miles by three quarters, or quadruple the efficiency of elctric vehicles or some combination of both.
You dont NEED more power to do the same charging. Keep in mind that you have to have an inverter to convert electricity from 110 volts to 10 or 12 volts: this causes a LOT of energy to be 'lost' in the process. Secondly, current battery diodes arent capable of higher voltage charging, which is what makes the new Toshiba Battery so unique.
These new batteries can take a higher voltage of current running th rough them, meaning less energy is lost in conversion. You dont actually use more energy to charge the battery in a shorter period of time, you just charge them more efficiently for less power overall.
Hothgor,
I suspect a lot of what you are saying is incorrect. For a start inverters don't convert AC to DC it's the other way around. Transformer rectifiers convert AC to DC. You state new batteries can take higher voltages of current. This is in correct, current is measured in AMPS not voltage and diodes control the direction of current not the amount going through them. I haven't time to look at the grid calculations but if the above is any indication it won't add up
So, the main point is that the current US coal + nuclear base loaded electrical generation system has suffient capacity to recharge the US fleet of gasoline cars, and probably enough to also charge the diesel burning ones, too. Cause for celebration, no? Maybe we can then go back to exporting oil.
Next, just replace the coal plants with 500 new nukes, and we can meet kyoto.
All we need is to persuade japan/korea/china to ship us 300 million new cars and 500 nukes in exchange for our highly desirable paper... We live on too high a plane to make this stuff ourselves.
I think you are forgeting how current-limited the grid is at the local neighborhood level. Even with intelligent appliances installed everywhere: fast, high amperage battery recharge cycles would still be limited by wiring safety limits. Therefore recharge cycles will take much longer than the theoretical ideal, unless we rewire every neighborhood [not likely]. Therefore, it will just take a certain # of fat-cat PHEVs to shutoff the heat, A/C, and refrigerators for the rest of their neighbors during the overnight battery recharge cycle. They won't be happy campers.
I am no engineer, but battery powered bicycles recharging everywhere would probably not overwhelm the current wiring limits of a neighborhood because the amp-draw is so low. No need for "smart appliances" either--which most people will not be able to afford postPeak anyhow.
But I could be wrong as this is speculation with no supporting facts. I just wanted to point out this potential roadblock to the dream of providing PHEVs for everyone. You might have better facts.
If the fast charge time he notes ends up being more than vaporware, it doesn't mean that it NEEDS to be charged that fast. It just opens up the possibility that it could - and that the retail market segment currently occupied by gas stations could retrofit with flow batteries, a major transmission line, and recharging terminals.
Thxs for responding. Good possibility that your reply might be the best cost-effective response vs rewiring neighborhoods. If the potential energy savings are so high by PHEVs--how come all the delivery trucks are not converting over?--I don't understand why the trucking industry is not spear-heading this conversion now: a massive fleet re-design if the cost savings are so obvious. Do you have an answer?
I am in favor of everything TODer AlanfromBigEasy suggests, but we will still need local delivery vehicles. It seems to me that the international emphasis should be on truck-PHEVs, and not personal PHEVs. Toyota, GMC, MACK, Peterbilt, etc, should be building RIGHT NOW big fleets of Truck-Prius, instead of personal cars IMO, and finalizing the designs for battery powered PHEV trucks. I will gladly pedal a bicycle everywhere as a tradeoff to having food delivered to my local supermarket.
Long haul PHEV truckers could have truck stops where the battery packs are quickly switched out by forklifts to get them back on the road soon. I greatly worry that the trucking industry is not Peakoil Aware--at the very least we should already have PHEV fire-trucks and ambulances.
Attention: TODer Gail the Actuary--I think the insurance industry and other corporations would be frantic for PHEV firetrucks, if they are looking ahead--Do you have any idea why not? Thxs for any reply.
As always great insight. I know that someone on this board months ago chimed in on this in relation to Volvo's plans. I can't remember what was said, so I won't lead you astray. This was coming from a guy working on the lines. I did a search and found that Magnus Redin is in Sweden, and he is mentioning something to do with Fords investment in their hybrids, but I don't remember if this is similar.
Thxs for responding. Yeah, truckers are not worried about fast acceleration like a TESLA sports car owner. But the high torque levels of an electric motor is IDEAL when you are hauling 80,000 lbs of cement, watermelon, lumber, beer, or whatever, in a big rig. Regenerative braking could be a big safety PLUS when these monsters have a long, steep downgrade ahead of them too. Much better than the current system of having your air-brakes fail, then the trucker hoping and praying that somehow he can control the rig until he can hit the offroad gravel safety runaway at the bottom of the hill.
We've got a section of Interstate 44 near our six flags that goes down a STEEP hill. When I had my stick shift I used to take the clutch completely out and coast down it at over 90Mph (had a sporty car). It's STEEP and there are accidents around that section all the time and it's especially bad when there is traffic. In the last couple of years there have been like 15 deaths including an entire family. The more I learn about EV, the more I tend to like it.
It's not quite as easy as it sounds to recover all that energy, especially for long hills. I reference you the always entertaining, always informative Dan.
It's pretty easy to recover most of that energy, as the previous poster indicated, just turn your engine off and put your car in neutral. You don't even need to store anything. Granted you're not actually saving the energy, but by not using energy on the way down in a way you are displacing some not-used gasoline. :)
I use this trick all the time when going downhill. In a manual you can even turn the car off completely and just bump start the engine when you get to the bottom. Not sure I would try it at 90 MPH, of course...
With an electric motor and battery you could store some of the excess (going 90 MPH is not really all that safe most of the time). Even though you get only a small fraction of the energy through regenerative braking, it's still "free" energy.
Think about the vehicle market for a moment. You have automobile companies that are selling vehicles for near cost. These same companies have a mechanical shop at every dealership nationwide. The average ROI for a car doesnt just stop at the purchasing price: they EXPECT the cars to have problems and require that a mechanic be there to fix them.
So where has that led us too? We have mechanic shops all across the companies and at every dealership: the parts that they used are sold by the same car manufacturers you got the car from in the first place. The price to fix the cars helps increase the car companies margins. And what about the oil servicing industy. On the trip home from work today, I passed 5 different oil changing businesses. Where do the parts and material they use come from?
When you look at the big picture, you can see why the auto industry has been against the EV potential. Why would any sane business produce a car that has less then half the current movable parts and is less prone to breaking down over its lifetime? There's no money in a super efficient EV when your entire business model has been based on the assumption that the cars will utilize the high margin secondary markets!
Thxs for responding. Truckers feel ripped off if the big-rig they purchased doesn't last a million miles with a reasonable amount of repairs/rebuilds. They want reliability and max uptime to earn income; there is not a lot more to be gained in further aerodynamic improvements when hauling large, bulky loads. If truck PHEVs have lower lifetime operating costs, improved safety and uptime improvements, and vastly lower emissions over present day diesel rigs--some manufacturer will get rich by being the first to market these vehicles.
Truckers are log-book limited by Fed law on how many hours they can drive in a day. I think tagteam truckers would gladly welcome one driver working the quiet electric drive while the other got silent, peaceful shuteye in the cabin bunk. Cooling the drivers' cab is nothing compared to the A/C required to keep a forty foot long trailer of ice cream cold.
I doubt PHEVs are that practical for big rigs for precisely the reason you mentioned: tag team drivers. What is the point of a truck that can be plugged in to recharge if it's going to be running the vast majority of the time? If there is not significant downtime then the plug-in aspect is not that helpful.
As for normal hybrid trucks, I think the reality is the way trucks are driven (primarily on the freeway at more or less constan speeds) limits the impact a hybrid drive can have on efficiency. A gas or diesel engine is most efficient when operating at constant speeds like on the freeway.
You can see this born out in the fuel economy figures of regular cars and hybrids. Much of the increase in hybrid gas mileage is under city driving conditions. On the freeway hybrids get better fuel economy, but most of that is a result of them having a smaller engine (since the electric motor is used to help accelerate when necessary). In reality the electric motor on a hybrid is rarely in operation on the freeway, and a car with a similar engine minus the hybrid components would do just about as well in terms of FEC. The non-hybrid car would not accelerate as well or go uphill as well without the electric assist, however.
A normal hybrid truck would still have some advantage over a non-hybrid, but it would not be that huge under freeway driving conditions. Going back to PHEV trucks, a better option is just to use electrified rail, not that PHEV trucks might not some day be the norm.
I think the answer as to why the insurance industry and other corporation are not frantic for PHEV firetrucks is in the second part of your sentence - they are not looking ahead.
Other issues - One might think that emergency vehicles will be given first dibs on whatever fuel is available. Also, emergency vehicles are driven relatively little, so I would expect would last a long time. A disproportionately large share of their fossil fuel use would go into their manufacture, rather than their day to day use.
Actually, I expect most PEVs and EVs to recharged via onsite solar systems that charge up over a given period of time, then are discharged into the car batteries. The amount of energy burdeon on the grid will be minimalized this way. And I know, I know, solar systems arent widespread currently. I expect the solar recharging systems to be included in the cost of the vehicle. The tesla currently has one for sale with it for a cost of about $5,000. Prices have declined significantly over the years, and will continue to do so in the future. In 10 years time, I expect a number of vehicles on the road that are EVs will outnumber even hybrids :P
I don't understand the units, but the chart from this site that I posted in my office shows "distributed electricity" at 11.9 and "transportation" at 21.2. Transportation would include airplanes, trucks, etc. But anyway that should get the scales set in the ballpark.
This site, from US DOE, shows the breakdown of all energy flows in the US, in quads, or quadrillion btus of energy.
It shows that total electrical power generation is 38 quads, used 19 quads residentical/commercial, and 19 quads industrial.
transport uses 26.5 quads
(chemicals, etc., use another 6 quads of petrol).
It also shows electricity generation results in lossesof 69% waste energy, and transport fuel at 80% lost energy. (Not that great a difference. Electricity is 31% efficient, petrol 20% efficient...)
If coal is 31% efficient at being turned into electricity, and then, to be usable for EVs, has to go through transmission lines and transformers, and then accept losses becoming battery power, I wonder whether it really IS more efficent than gasoline?
Also, since (realistically), any increase in electrical generation will be coming from coal, that would entail almost a doubling of coal excavation! (20 quads of coal now, plus perhaps another 16 quads to power our EV Hummers).
1 gallon of gas = 130.88 MJ stored energy
130.88 mj ~ 36.35 kw/h equivlant, or about what you stated.
Now here is where it gets tricky. The average consumer car only has a 12% efficiency from gasoline. That means for every gallon of gas, only 12% of the stored energy content is used to propell the vehicle. The most efficient ICE, a diesel, gets about 18.5% efficiency fyi.
36.35 kw/h x .12 = 4.362 kw/h
That is to say that the same energy in electrical power to propell the car is about 4.362 kw/h! Now, you have stated that wiki shows that EV engines are 4x more efficient.
4.362 x .25 = 1.0905 kw/h
Does it take 1.0905 kw/h to power an EV to go the same distance a comparable ICE goes?
Even if you use the same efficiency of 4.362 kw/h, thats still only 76.335 GW/h over the course of one night, ASUMING EVERYONE PLUGS IN THEIR CAR AND RECHARGES OVER THE ENTIRE NIGHT!!! In practice, it will be FAR LESS on the average night.
Note: this is based on the assumption that the average user would still drive about 30 miles a day, and are in far more efficient vehicles, not behemoths like an SUV. Most small cars do get 30 mpg :P
You're making it too hard. If an EV is on average 4 times as efficient as an ICE, then you take the energy content in all the gasoline used by ICEs, divide by 4 and you have the electrical energy you need to replace it. Your 0.12 factor is included in that efficiency ratio.
If yoyu want to replace the existing daily usage of 400 million gallons of gasoline, you need to come up with the electrical energy equivalent of 100 million (10^8) gallons. That's about 36.5*10^8 KWH, or 3.65 billion KWH, which of course is 3,650 GWH per day.
It doesn't matter how long you take to recharge your cars, the system overall needs to deliver 3,650 GWH of energy to vehicles in the USA every day to maintain the same transportation capacity.
Byu the way, here's where that 4:1 ratio comes from, in the Wikipedia article on electric cars:
Production and conversion BEVs typically use 0.3 to 0.5 kilowatt-hours per mile (0.2-0.3 kWh/km). [7] [8] Nearly half of this power consumption is due to inefficiencies in charging the batteries. The US fleet average of 23 miles per gallon of gasoline is equivalent to 1.58 kilowatt-hours per mile and the 70 MPG Honda Insight gets 0.52 kWh/mi (assuming 36.4 kWh per US gallon of gasoline), so battery electric vehicles are relatively energy efficient.
1.58/0.4 is right about 4:1. As the article imples, better charging technology will boost that somewhat, but that's what we have right now.
There are currently aprox 210 million vehicles on the road at present. Thats where the 210 million comes through. Cmon, you gotta give me the procs on showing you how your math was wrong :P
I'm intrigued. How did you come up with the energy equivalent of 57GW? Does the 220 Million figure includes all cars and trucks including tractor trailers?
The truth is this applies to cars too, and actually you can roll quite fast on even a very slight incline as a result of the car's weight. I think many people are under the assumption that without the engine pushing constantly the car would just stop, but that is not true (if you have a manual it's easy to push the clutch in, it can be impressive sometimes just how far you can roll with no power input whatsoever).
Once a car is actually rolling it doesn't necessarily require that much power to keep it in motion, especially with low rolling resistance tires. On the other hand with AC we have the issue that people are trying to keep their houses well below the ambient outdoor temperatures. When you're trying to keep your house 20-25 degrees below the ambient outdoor temperature you are just going to waste tons and tons of energy. It's kind of like running uphill, you are spending a lot of energy fighting the laws of nature. An AC will be running basically nonstop during the day, whereas on average a car will not be in motion more than a small fraction of the day.
The USA currently uses about 320 million gallons of gasoline in a day. A gallon of gasoline yields around 36.6 KWH, so the heat energy in the gasoline used in one day in the USA is about 12,000 GWH.
According to a Wikipedia article, electric vehicles are about 4 times as energy efficient as gasoline vehicles. If all the cars burning all that gasoline were converted to elctric drive, the efficiency gain would require 3,000 GWH per day. If all vehicles were recharged in a 12-hour off period, this would require an average capacity of 250 GW, or about 25% of the nominal grid capacity.
How do you get 57 GW?
- Current battery recharging and discharging technology is well, technologically backwards. When you recharge a battery, only a fraction of the energy used actually gets stored in the battery. The rest is lost to heat. Dont believe me? Go and recharge your cell phone and then pick it up and feel how 'warm' the back side of it is, where the battery is located. Also, take a look at most laptop batteries and how hot they get. The heat produced by the computer doesnt cause all the heat to be localized in one location...
- The Tesla itself takes only 3 hours to go from completely drained to a full charge. Far less then the 12 hour time period you expect the plugged in cars to drain energy from the grid.
- The new batteries such as the one Toshiba developed take a fraction of the time current batteries take to recharge. These new batteries have the potential to be ~80% recharged in ONE MINUTE. Think about that for a second before you dismiss PEVs outright.
- The ICE you are probably currently driving around only has an efficiency of less then 18%. That means for the 134,000 btu of energy stored in each gallon of gasoline, your only using at most 24,120 btus to move your car. The rest is lost to heat. To prove this to yourself, go and drive about 150 miles, then park and have a seat on your supposedly nice and cool engine cover.
- Electric cars are VASTLY more efficent and using energy then ICEs are. And the ironic thing about EVs, the more powerful the electric motor is, the more efficient it becomes. Thats why vehicles like the Tesla have a 185 hp electric motor when many people point out that you really only need about 50hp to get the job done. It's all about efficiency.
- Obviously, any massive EV scale up would require the usage of 'smart' recharging appliances. These appliances would be able to determine weather or not the energy grid is 'spikeing' due to excessive power drainage, or if energy usage is low and it is safe to recharge the batteries.
- The Tesla and the upcoming 4 door sedan are stated to have a range of about 250 miles per charge. The nationwide AVERAGE miles per day per vehicle is about 30 miles. That means that on average, you will drive around 30 miles a day to do all your shopping, getting to and from work and any other trips you make. That means you technically only need to recharge ~once every 8 days. Lets just place that figure on a nice 1 day a week recharge period for the AVERAGE driver.
----Now what does this all mean? It wont take 257 GHw of electricity every night to recharge the vehicle, it will take ~37 ghw a night, asuming INTELLIGENT recharging with intelligent applications by the consumers. Comments?
So that means you will need more energy in total than just the amount expended in motion. That doesn't help your case.
Charging time doesn't matter. What matters is the amount of energy drawn from the grid. Shorter time = higher current. The energy requirement remains the same.
Again, charge time isn't the issue. A shorter charge time may make it easier for power companies to regulate the smart chargers and prevent grid overload, but it doesn't change the amount of power they will need to provide.
As I said above, the efficiency advantage of electrics over fossil fuelled ICE is well known. The advantage is given as 4:1 by this Wikipedia article. That was factored into my analysis above.
This is a given for preventing grid overload. It doesn't address the total amount of energy needed.
If you maintain the passenger-miles currently driven and just change the energy source, you wind up with the numbers I calculated above. Here you are moving the goalposts by assuming a change in driving habits.
My analysis stands - 250 GW supplied for 12 hours per day is required to replace the transportation capability provided by gasoline engines today. You can cut that energy requirement by changing people's driving habits, but to get it to 57 GW (I assume 37 was a typo?) you'd have to cut the passenger miles by three quarters, or quadruple the efficiency of elctric vehicles or some combination of both.
I still don't see how you got 57 GW.
These new batteries can take a higher voltage of current running th rough them, meaning less energy is lost in conversion. You dont actually use more energy to charge the battery in a shorter period of time, you just charge them more efficiently for less power overall.
I suspect a lot of what you are saying is incorrect. For a start inverters don't convert AC to DC it's the other way around. Transformer rectifiers convert AC to DC. You state new batteries can take higher voltages of current. This is in correct, current is measured in AMPS not voltage and diodes control the direction of current not the amount going through them. I haven't time to look at the grid calculations but if the above is any indication it won't add up
Next, just replace the coal plants with 500 new nukes, and we can meet kyoto.
All we need is to persuade japan/korea/china to ship us 300 million new cars and 500 nukes in exchange for our highly desirable paper... We live on too high a plane to make this stuff ourselves.
I think you are forgeting how current-limited the grid is at the local neighborhood level. Even with intelligent appliances installed everywhere: fast, high amperage battery recharge cycles would still be limited by wiring safety limits. Therefore recharge cycles will take much longer than the theoretical ideal, unless we rewire every neighborhood [not likely]. Therefore, it will just take a certain # of fat-cat PHEVs to shutoff the heat, A/C, and refrigerators for the rest of their neighbors during the overnight battery recharge cycle. They won't be happy campers.
I am no engineer, but battery powered bicycles recharging everywhere would probably not overwhelm the current wiring limits of a neighborhood because the amp-draw is so low. No need for "smart appliances" either--which most people will not be able to afford postPeak anyhow.
But I could be wrong as this is speculation with no supporting facts. I just wanted to point out this potential roadblock to the dream of providing PHEVs for everyone. You might have better facts.
Bob Shaw in Phx,Az Are Humans Smarter than Yeast?
Thxs for responding. Good possibility that your reply might be the best cost-effective response vs rewiring neighborhoods. If the potential energy savings are so high by PHEVs--how come all the delivery trucks are not converting over?--I don't understand why the trucking industry is not spear-heading this conversion now: a massive fleet re-design if the cost savings are so obvious. Do you have an answer?
I am in favor of everything TODer AlanfromBigEasy suggests, but we will still need local delivery vehicles. It seems to me that the international emphasis should be on truck-PHEVs, and not personal PHEVs. Toyota, GMC, MACK, Peterbilt, etc, should be building RIGHT NOW big fleets of Truck-Prius, instead of personal cars IMO, and finalizing the designs for battery powered PHEV trucks. I will gladly pedal a bicycle everywhere as a tradeoff to having food delivered to my local supermarket.
Long haul PHEV truckers could have truck stops where the battery packs are quickly switched out by forklifts to get them back on the road soon. I greatly worry that the trucking industry is not Peakoil Aware--at the very least we should already have PHEV fire-trucks and ambulances.
Attention: TODer Gail the Actuary--I think the insurance industry and other corporations would be frantic for PHEV firetrucks, if they are looking ahead--Do you have any idea why not? Thxs for any reply.
Bob Shaw in Phx,Az Are Humans Smarter than Yeast?
As always great insight. I know that someone on this board months ago chimed in on this in relation to Volvo's plans. I can't remember what was said, so I won't lead you astray. This was coming from a guy working on the lines. I did a search and found that Magnus Redin is in Sweden, and he is mentioning something to do with Fords investment in their hybrids, but I don't remember if this is similar.
http://www.theoildrum.com/comments/2006/7/16/92623/0023/191#191
Thxs for responding. Yeah, truckers are not worried about fast acceleration like a TESLA sports car owner. But the high torque levels of an electric motor is IDEAL when you are hauling 80,000 lbs of cement, watermelon, lumber, beer, or whatever, in a big rig. Regenerative braking could be a big safety PLUS when these monsters have a long, steep downgrade ahead of them too. Much better than the current system of having your air-brakes fail, then the trucker hoping and praying that somehow he can control the rig until he can hit the offroad gravel safety runaway at the bottom of the hill.
Bob Shaw in Phx,Az Are Humans Smarter than Yeast?
I use this trick all the time when going downhill. In a manual you can even turn the car off completely and just bump start the engine when you get to the bottom. Not sure I would try it at 90 MPH, of course...
With an electric motor and battery you could store some of the excess (going 90 MPH is not really all that safe most of the time). Even though you get only a small fraction of the energy through regenerative braking, it's still "free" energy.
So where has that led us too? We have mechanic shops all across the companies and at every dealership: the parts that they used are sold by the same car manufacturers you got the car from in the first place. The price to fix the cars helps increase the car companies margins. And what about the oil servicing industy. On the trip home from work today, I passed 5 different oil changing businesses. Where do the parts and material they use come from?
When you look at the big picture, you can see why the auto industry has been against the EV potential. Why would any sane business produce a car that has less then half the current movable parts and is less prone to breaking down over its lifetime? There's no money in a super efficient EV when your entire business model has been based on the assumption that the cars will utilize the high margin secondary markets!
Thxs for responding. Truckers feel ripped off if the big-rig they purchased doesn't last a million miles with a reasonable amount of repairs/rebuilds. They want reliability and max uptime to earn income; there is not a lot more to be gained in further aerodynamic improvements when hauling large, bulky loads. If truck PHEVs have lower lifetime operating costs, improved safety and uptime improvements, and vastly lower emissions over present day diesel rigs--some manufacturer will get rich by being the first to market these vehicles.
Truckers are log-book limited by Fed law on how many hours they can drive in a day. I think tagteam truckers would gladly welcome one driver working the quiet electric drive while the other got silent, peaceful shuteye in the cabin bunk. Cooling the drivers' cab is nothing compared to the A/C required to keep a forty foot long trailer of ice cream cold.
Bob Shaw in Phx,Az Are Humans Smarter than Yeast?
As for normal hybrid trucks, I think the reality is the way trucks are driven (primarily on the freeway at more or less constan speeds) limits the impact a hybrid drive can have on efficiency. A gas or diesel engine is most efficient when operating at constant speeds like on the freeway.
You can see this born out in the fuel economy figures of regular cars and hybrids. Much of the increase in hybrid gas mileage is under city driving conditions. On the freeway hybrids get better fuel economy, but most of that is a result of them having a smaller engine (since the electric motor is used to help accelerate when necessary). In reality the electric motor on a hybrid is rarely in operation on the freeway, and a car with a similar engine minus the hybrid components would do just about as well in terms of FEC. The non-hybrid car would not accelerate as well or go uphill as well without the electric assist, however.
A normal hybrid truck would still have some advantage over a non-hybrid, but it would not be that huge under freeway driving conditions. Going back to PHEV trucks, a better option is just to use electrified rail, not that PHEV trucks might not some day be the norm.
Postal & UPS delivery vehicles might be good candidates for hybrid technology (hydraulic storage rather than battery perhaps).
Best Hopes,
Alan
Other issues - One might think that emergency vehicles will be given first dibs on whatever fuel is available. Also, emergency vehicles are driven relatively little, so I would expect would last a long time. A disproportionately large share of their fossil fuel use would go into their manufacture, rather than their day to day use.
http://eed.llnl.gov/flow/
I don't understand the units, but the chart from this site that I posted in my office shows "distributed electricity" at 11.9 and "transportation" at 21.2. Transportation would include airplanes, trucks, etc. But anyway that should get the scales set in the ballpark.
This site, from US DOE, shows the breakdown of all energy flows in the US, in quads, or quadrillion btus of energy.
It shows that total electrical power generation is 38 quads, used 19 quads residentical/commercial, and 19 quads industrial.
transport uses 26.5 quads
(chemicals, etc., use another 6 quads of petrol).
It also shows electricity generation results in lossesof 69% waste energy, and transport fuel at 80% lost energy. (Not that great a difference. Electricity is 31% efficient, petrol 20% efficient...)
If coal is 31% efficient at being turned into electricity, and then, to be usable for EVs, has to go through transmission lines and transformers, and then accept losses becoming battery power, I wonder whether it really IS more efficent than gasoline?
Also, since (realistically), any increase in electrical generation will be coming from coal, that would entail almost a doubling of coal excavation! (20 quads of coal now, plus perhaps another 16 quads to power our EV Hummers).
1 gallon of gas = 130.88 MJ stored energy
130.88 mj ~ 36.35 kw/h equivlant, or about what you stated.
Now here is where it gets tricky. The average consumer car only has a 12% efficiency from gasoline. That means for every gallon of gas, only 12% of the stored energy content is used to propell the vehicle. The most efficient ICE, a diesel, gets about 18.5% efficiency fyi.
36.35 kw/h x .12 = 4.362 kw/h
That is to say that the same energy in electrical power to propell the car is about 4.362 kw/h! Now, you have stated that wiki shows that EV engines are 4x more efficient.
4.362 x .25 = 1.0905 kw/h
Does it take 1.0905 kw/h to power an EV to go the same distance a comparable ICE goes?
210,000,000 x 1.0905 kw/h = 229005000 kw/h
229005000 kw/h =~ 229.005 GW/h
229.005 GW/h / 12 hours = 19.08375 GW/h needed!
Even if you use the same efficiency of 4.362 kw/h, thats still only 76.335 GW/h over the course of one night, ASUMING EVERYONE PLUGS IN THEIR CAR AND RECHARGES OVER THE ENTIRE NIGHT!!! In practice, it will be FAR LESS on the average night.
I bet you didnt think I would do my homework :P
You're making it too hard. If an EV is on average 4 times as efficient as an ICE, then you take the energy content in all the gasoline used by ICEs, divide by 4 and you have the electrical energy you need to replace it. Your 0.12 factor is included in that efficiency ratio.
If yoyu want to replace the existing daily usage of 400 million gallons of gasoline, you need to come up with the electrical energy equivalent of 100 million (10^8) gallons. That's about 36.5*10^8 KWH, or 3.65 billion KWH, which of course is 3,650 GWH per day.
It doesn't matter how long you take to recharge your cars, the system overall needs to deliver 3,650 GWH of energy to vehicles in the USA every day to maintain the same transportation capacity.
Byu the way, here's where that 4:1 ratio comes from, in the Wikipedia article on electric cars:
1.58/0.4 is right about 4:1. As the article imples, better charging technology will boost that somewhat, but that's what we have right now.