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Otis
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However there is detonation limit to how much boost you run with a spark ignition engine. A turbocharger is basically a positive feedback device (more boost generates more exhaust which generates more boost, etc) so you can not run a turbocharger without someway to limit the boost otherwise something will blow up. Electric turbocharger/generator can give you plenty of control over boost, and can likely obviate a blowoff valve except possibly having one for emergency purposes, since you would simply run the generator to bleed off excessive turbine speed. Couple this with an Atkinson-cycle valve configuration and you have an on-demand Miller cycle engine, which could be switched from Eco mode (Atkinson, say 30-40kW) to Power mode (Miller, say 120kW) by adding boost and fuel.
All EVs will plug-in to households, specifically complementing utility grids or ultimately overwheming them with high demand, followed by the need to increase decentralized power generation. Battery capacity is the key. Do we want a utility grid to daily recharge 10 (85kwh)Telsa coupes or 170 (5kwh)PHEVs? The smaller PHEV battery pack is also the more ideal match to rooftop solar arrays. Oh not this tired meme again. EVs typically charge at night or during off-peak hours (for example, after a morning commute whereby the vehicle charges in the AM before peak hours begin), therefore their effect on peak load is minimal, gradual and predictable. EVs and PHEVs at a steady growth rate provide plenty of time for utilities to grow their capacity and plan their infrastructure upgrades accordingly. In fact, those upgrades can often be rolled into maintenance that already would have happened without EV demand. EVs are something of a godsend to utilities, since they draw power that would otherwise be wasted base load overnight, it's almost free money for them! And all this chatter about utilities encountering capacity problems, let's just say one thing: if they start having problems with peak demand, let them put Time of Use plans in place; any place that does not have ToU pricing doesn't have to worry about EVs unless they're forbidden from ToU by government fiat.
I certainly hope their software engineering and management is up to snuff, and that they can quickly take advantage of upgrades in the ARM platform ecosystem. I also wonder if power-hungry NVidia is a culprit in the whole vampire loss problem Tesla's been dealing with for several firmware versions now. Tegra 3 is something like 2 processes back at 40nm, state of the art is 22nm or smaller now...
Version P85D has rear motor unchanged, 470 hp, while adding a front motor of 221 hp for a price premium of $14,600. Assuming that the $4,000 is for the front differential and a pair of CV joints, then the front motor costs nearly $10,000? A combustion engine of the same power would cost half to a third of that. P85D is a pure profit grab, which is fine, because people will pay that much for that level of performance. It's what the market will bear. In about 3 years, I reckon the successor to the current 'Insane' tier Model S will be a 110-120kWh monster with front and rear 500kW motors (or 4x250kW) with each 'axle' geared differently, with a peak discharge from the battery of 7C. 120 * 7 = 840kW, which equates to about 1100hp. Weight will likely be in the 2200-2300kg range, given the increased mass of motor, wheel, tire, and with the battery growing just a bit given density improvements.
Dual motors give you: * improved acceleration * ability to run taller final drive gearing in front, thus improving efficiency at higher speeds * redundancy in case of one drive failure * improved regeneration given that the front axle bears the brunt of deceleration * torque vectoring with appropriately-controllable diffs (though quad-motor would likely be better) Dual motors is really the way to go, and I reckon uptake on that option will be pretty high given the benefits.
How many kWh net per gallon of diesel? Also, 50kW would be better.
Not bad for routes that have long (or high-speed) stretches between charging points, though CNG hybrid would be a better option IMO. With $50/kW SOFCs that could take CNG directly, it would be even better. I think I still like the Proterra bus a bit more though, even if it requires a bit of additional infrastructure to accomodate in-transit quick charging.
Howsabout an Atkinson/Miller range extender with electric supercharger, exhaust-gas-driven generator and turbosteamer? Call it 1l 3cyl, with 30kW Atkinson cam profile normally-aspirated with reclamation of exhaust heat via the generator under typical <=70mph operation, with a demand mode that brings it up to 100kW.
Put a Voltec drivetrain in this with some more power and battery, call it the Electra, and triple or quadruple Volt sales from day 1.
To be fair, Model S Supercharging looks like it currently ranges between 1.5 and 2C. I guess the jury is still out, but my prediction is that apart from some extreme outliers (long distance drivers and/or cheapskates) Tesla can keep Supercharging percentages down thanks to placement out-of-the-way in between cities, at least in the US. And if 2C is considered high, then companies that think they can scrimp on battery to achieve a range figure will end up getting stuck in the slow-charging lane. It's science: 100kW is the _minimum_ for practical intercity charging, 250kW is a pivot-point. To achieve those power levels, you need batteries that can accept them. Those batteries can do so either via power-tolerant chemistry that's TBD or by scaling up their size. The latter is much less of a technology risk than the former, so if you really mean to sell a practical, normal-livable EV-as-only-vehicle you really need to do the latter.
Double the power, double the energy, for starters. 2010 called, it wants its state of the art EV back.
I'm confident that if we have a robust charging infrastructure using 90kW CCS here in the states, then people would feel more comfortable with ~100 mile range vehicles. Call it 100kW baseline, with a 33kWh usable battery for 100mi of range. Which battery chemistry can be charged at 3C regularly and be economically warranted for 8 years and 100000 miles with no more than 20% capacity loss? Plus, that infrastructure would need multiple chargepoints at no more than 50mi apart to be practical. There's so many good things you get with bigger batteries, and which scale with size: energy, power, charge rate. They all go together.
Have thermoelectric conversion efficiencies improved much beyond a more traditional Turbosteamer-style system? http://www.greencarcongress.com/2011/08/bmwthermal-20110830.html
Is diesel commonly available at airports? Can this engine also run on jet fuel?
Another difference is the F150 still uses a steel frame, only body parts are aluminum. F-150 is a body-on-frame design, so it's a bit more than that.. Basically, everything that would be aluminum in a typical unibody car is aluminum in the F-150: the passenger cell, the 'trunk', etc.
250kW Supercharging is the minimum to silence EV naysayers IMO, as getting a full 200mi charge would then take on the order of 15 minutes. I don't see that as being even a seriously-contemplated idea until there's 120+ kWh batteries available though.
I wonder if they could extend the shaft out and integrate a motor/generator into the design, so that it could be spun up by external power at low RPMs, and generate usable power instead of wastegating excessive pressure.
How much power is left to squeeze out of exhaust gas heat? Cuz it seems that a turbine generator in the exhaust stream would be good for range extending gensets..
Stick 100kW/400Nm motor at each corner (or basically 4xSpark EV motors), add 40kWh battery and 100kW range free-piston linear motor extender. Gear the front motors for highway efficiency, rear motors for launch and city power. Add a 'boost' button to burst the battery at ~10C for short periods, as energy and thermals permit, with a WoW-esque cooldown timer. That should be enough torque for most families' towing needs, and performance like nothing else.
The only way there'll be widespread H2 infrastructure for fuelling cars that doesn't involve piggybacking on NG pipelines is if there's LFTRs in every state if not county putting out electricity at half a cent per kWh or less, and onsite electrohydrolysis. I find reformulation of NG a lot more likely. Depending on the efficiency/cost that could still be a net win over refining and distributing gasoline/diesel.
How many kWh can the hydrogen out of a reformulated gallon of gas (or GGE from natural gas reformulation) get out of these fuel cells? Needs to be at least 16kWh to be interesting IMO..
Would adding an exhaust-gas turbine generator be worth doing?
If the total engine efficiency could be boosted from 40% to 60%, fuel consumption would drop by a third; electrification of much of the propulsion system would allow further improvements from e.g. boundary-layer control. Would efficiency be improvable even further by adding a stage to take advantage of exhaust heat, then the cooled unburned fuel could be burned in a final stage? Intake -> Electric fans -> Hot SOFC exhaust air/fuel stage -> cool air/fuel ignited stage -> exhaust So you'd have an electric stage, an "external combustion" stage and an "internal combustion" stage. I tend to think insulated EGR would be a better idea with the SOFC, especially since there shouldn't be any particulates.
Any way you slice it, SOFC is not practical for automotive use if it costs any more than $0.10/W , and $0.03-0.05/W is a lot more realistic. For aviation use, call the GE90 turbofan 90MW for $20MM, or ~$0.22/W, so maybe $0.15-$0.20/W is acceptable in that application.