At low speeds, most fuel expenditure is on braking, which is recovered by an EV. At motorway speeds, most fuel goes on overcoming wind resistance, which is the same for all types of car.
By the way, the much-maligned C5 from Uncle Clive (it always amuses me to see a Citroen labelled 'C5') had regenerative braking, which provided battery assistance to the pedals.
Is that the one with the Electric Porsche? A friend of mine has one of those. They recently updated his software for the heads up display and screens now he needs to re learn where everything is!
Brian
Is that the one with the Electric Porsche? A friend of mine has one of those. They recently updated his software for the heads up display and screens now he needs to re learn where everything is!
Brian
Longer distance travel is covered by the 'petrol' bit of PHEV.
The batteries in PHEVs tend to quite small - maybe 20 mile range. Certainly far more expensive than a lead acid, but should see out a decade of use.
Oops - P is plug-in - H is the hybrid ICE/electric.
I've now done 2 "over 400 miles each way" journeys in my battery Skoda. Having decided before I got the BEV that I was not going to drive that sort of distance in one day, I haven't found a problem. There are superfast chargers if you look and a break for lunch will set me up for another 200 miles.
The calculation is based on the mixed use figures, so some town driving, some motorway and some country roads.
My calulation was based on my current car, which gets 33 to the gallon and and an electric car that gets around 4 miles per kWh.
Sure.
But plenty keep their car for more than a decade.
Which f*ck the life of your very expensive battery.
I don't bother with lunch or any meal when on a trip like that.
Well Siemens took that problem seriously when they built the new trains used by ?South West Railways. They actually built their own test track in Germany, complete with all the wibbly wobbly defects that are to be found on Southern Region
3rd rail tracks - simply to make sure that their trains could cope with the sort of track that would never be accepted as 'normal' in Germany (or Switzerland, Austria,..)
One of the distorting influences on motors, is the price of neodymium.
Regen is complicated enough, I cannot find straight comparisons on which cars only do regen to 20MPH, and ones that can regen down to 0 MPH. Even in a series of comments of that type, what may be happening, is there is "braking force" down to 0 MPH on one of the motor types, but the car is not actually putting all the energy back in the battery. It might decide to dump the power into a resistor at some point instead.
In a diesel-electric locomotive, no attempt is made to "harvest" the braking energy. The electric motors dump their output into a resistive grid arranged near the cooling airflow in the top of the locomotive. The airflow up there, is not just to dump diesel exhaust, it's cooling for the resistors during braking. On a sufficiently steep grade, the regular friction brakes on the train might also need to be set. (Even the braking scheme on a train, is "scary-flaky" and you don't want to know how that subsystem works. When you park a train, you set the friction wheels on the cars manually, to ensure the train does not wander off. When a train wanders off, people die.)
The speed is still increasing.
You're not paying attention.
6GHz turbo, coming soon :-)*******
Not all technologies scale. When I took the HBT course at work (heterojunction bipolar), I asked the instructor whether the 2u transistors being used could be scaled down in future. And the answer was a flat "No" and that they would stay at 2 micron forever. When you make them smaller, they don't go faster
10GHz "Childs-play HBT" (the course I took) 40Ghz 100GHz The best a competitors HBT could do. 700Ghz The best that IBM can do, at the single transistor level. Real circuits will be slower than that. The 700GHz might be the unity gain point.HBT burns way too much power, to ever appear in your computer room. That's not what it is for. You do gear-grinders in HBT mostly.
CMOS on the other hand, is amazing stuff, as it has beat bookie odds a number of times. At first, it was held back by poly, but they stopped doing that and it went faster.
Another enemy of CMOS, is electromigration. That was compensated by changes in metallurgy.
They're using something other than copper now. I don't think the latest material choices are public knowledge.
And so the research continues.
Most of that is done by wasting electricity, but it is fun to pretend. There was a time, you could only do that with liquid nitrogen.
The latest liquid nitrogen record might have been around 8 GHz, but I don't pay attention to pointless stuff.
The operating voltage of CMOS is also nothing short of amazing. They breezed below the 1.0V level, like it was nothing. At idle, modern processors run at ridiculously low voltages. Looking at CPUZ a few moments ago, with hands-off-mouse, the VCore is 0.33 volts.
Paul
Before buying my PHEV I was a bit concerned by comments that this form of power train was very inefficient when doing long journeys, but finally decided that it was right for my circumstances as the vast majority of my journeys would be short and be electric and the would easily compensate for the odd long journey. However, I have been pleasantly surprised by the effect of regenerative braking and have even managed the odd electric drive where I had more electric miles on the clock when completed then when I started.
When the battery is depleted and the car goes into ICE mode that is not the end of electric assistance. The battery will not fully recharge from regenerative braking in AutoEV mode but does provide some electric miles. Oddly usually when going from standstill when it will drive a short distance on electric before the ICE cuts in and if you look at the journey computer it will continue to clock up electric driven miles. So it performs a bit like a mild hybrid perhaps not efficiently but compensating somewhat to the ICE mpg.
The car does have charging mode where you use the ICE to drive the car and at the same time charge the battery but the mpg is atrocious and I reckon it would take a journey of several hundred miles to fully recharge.
Richard
You make motive power from a chemical reaction, sometimes using heat, sometimes using electricity. If you use heat, ie burn fuel, then you only have to carry just one reagent, eg petrol, and the other reagent you suck out of the air. Also, you don't have to carry your spent reaction products around, you simply pump them out into the air.
[While people talk of the energy density of petrol, really it has approximately none on its own. Strike a match into petrol and not much will happen. Do it in air and you have a problem.]Practical automotive batteries have to carry all their reagents plus spent reaction products. The reagents are stored in close proximity which make this potentially unsafe, even at current energy densities.
Battery technology is bloody marvellous really. I can't wait till the motorways have Scalextric type slots, or overhead wires for charging trucks you hook your car up to in a train, or quick-swap battery packs etc etc. Meanwhile, you get less range with BEVs and they take much longer to 'fill up'.
Modern CMOS leaks.
Designs (e.g. desktop processors) which include vast numbers of circuits which are not actively switching still consume power because of this leakage current.
Leakage power is a significant portion of the total power consumed by such designs. Multi-threshold CMOS (MTCMOS), now available from foundries, is one approach to managing leakage power. With MTCMOS, high Vth transistors are used when switching speed is not critical, while low Vth transistors are used in speed sensitive paths."
The CMOS of long ago, didn't leak like that. With the clock stopped, a CMOS circuit could maintain state on battery for months or years. (That's also because the designs were fully-static and did not need a clock to refresh internal storage.)
Some of the original CMOS, ran at voltages from 5V to 15V.
Peak leakage for processors, was the Prescott era, where 25% of the electric power entering the processor was just wasted immediately as heat.
Paul
They are working on solid electrolyte batteries.
There are estimates of what the "max density" of a battery could be. But who knows, maybe the estimates are wrong.
And there might be batteries better suited for stationary storage. Even if a battery fails ruggedness testing, there may still be a place for it. An example, would be a battery bank in a truck stop charging BEV semis at megawatt levels.
Paul
Test track work is both important and useful, but, sadly, cannot reproduce all of the interface issues that can arise in actual operation.
Chris
I suppose it's something to do inbetween watching your GPU melt its cable and your PCIe riser catch fire ...
I regularly do 200+ mile trips without a break but with 400 miles I would do so but a UK motorway service area would be my least favourite place to stop.
As for shortening the life of the battery with fast charging some people can afford to ditch the car for a newer model long before battery life becomes an issue :) Fast charging is probably not something you want to do that often if you are going to keep a car for much of its natural life.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.