Electric cars are a pipe dream
- Thread starter Syzygys
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Are you asking if it will run on ammonia? It would but it would be pretty nasty; you'd need a catalyst to get it to burn and you'd have a lot of NOx emissions. I imagine a catalytic converter could clean up the exhaust though.
TPV converters run on anything that can burn. They are basically highly emissive hot radiators surrounded by low-frequency photovoltaic converters. The fuel keeps the radiator hot.
I would thought it was obvious that I was using incandescent bulbs to make exactly the same (but opposite) point! Who wants a light-bulb that delivers the vast majority of its output in Heat? Except in some very unusual cases this is to be avoided if possible - which CFL does! Likewise with a car motor, the 'work-done' that one want ALL year round is a moving car NOT heat.
So now your talking abut a Range Extender, yes?
That's fine, but the whole point of a plug-in BEV (rather than a hybrid) is that shorter journeys can be made with no on-board motor - under these situations a simple gas-burning heater on cold days is very much suited to the job.
These devices are still in their infancy and as such are expensive to implement at present, esp.for the small amount of electrical return. Also, you have the problem on it's head if you think having an inefficient device for turning chemical energy into mechanical work (a piston engine), that then has extra recovery devices 'bolted-on' post reaction - is ever going to compete well with an efficient means like a battery-bank running a well suited motor. It isn't.
But one also needs cooling, and so the simpler method to produce both in a Range Extended EV is to use the IC to produce electricity like it always does and use the electricity to drive an electrical heat pump, pumping heat either in or out as needed.
This is what is done in the Volt.
Arthur
Someone who needs a heater who could also use some additional light. (Or, in this case, someone who needs a heater but would also like some additional range.)
Right. But for longer distances there are problems (long recharge times etc.) An IC engine solves both of those problems - heat and range.
That's not to say that there's only one solution; a battery-only BEV with an advertised range of 100 miles will still get you to work and back if your place of work is 25 miles away with no fuel whatsoever even when it's cold, hot, rainy etc. For longer ranges, you need some method of getting additional energy into the vehicle. PHEV's are one way to do that.
Exactly! "Inefficient at producing electricity" is another way of saying "efficient at being a heater." As basic thermo tells us, wasted energy generally ends up as heat.
They all come with one already bolted on - the radiator. It's basically a heat exchanger that's good at transferring heat into the environment. Indeed, car heater cores are just small radiators.
The Volt uses its engine to drive the wheels. Its configuration is almost identical to a PHEV Prius. This is a good thing; ICE to wheels is a lot more efficient than ICE to generator to motor to wheels.
Agree on the compressor, though. A variable speed electrically driven compressor is radically more efficient than an engine driven compressor, mainly because you can tailor the compressor speed to the demand.
Only partly true, the Prius does most of its driving being propelled by the ICE, the Volt is just the opposite and only does it above 70 MPH, and then only in a direct drive manner (no trasmission), this avoids having to have a much larger electrical motor than is normally needed.
More to the point, if most of your driving is long distance and at 70+ MPH then neither the Prius or the Volt is likely to be a good choice.
Arthur
The Prius PHEV uses all electric power up to 34mph (2010 version) and 66mph (2012 OEM version.)
Both the Prius and the Volt have a planetary transmission between the ICE, motor and wheels. Toyota calls theirs a "power split device" - I don't know what GM calls theirs.
Maybe, but the 2010 car has very limited EV range and the 2012 car you are describing is not yet available and won't be for some time, at which time we can say what it actually does or doesn't do.
Yes, but they are still quite different in that most city/suburban users will never use the Volt's ICE to drive the car, typically only when you take it city to city will you hit over 70 and thus use the ICE to drive it.
Arthur
Thanks for leaving out the final part of my response to suit your answer:
I could have added (again) that batteries-controller-motor are much better at this than gas_tank-ICE-transmission over the wide range of normal driving. To reiterate the all-year-round point, unless you live in a particularly cold climate for much of the year the 'free-heat' (in very inverted commas) advantages do not make up for the full-year loss of efficiency.
Along the way of this thread it seems to have been forgotten that the discussion is primarily on straight BEVs - hence the thread title.
In the flavour of the OP, I would like to suggest that simple BEVs can play a part in the future transport mix - and in relation to these vehicles only, a NG heater could be a very good simple and cheap-to-build solution to cold cabins and cold battery packs (it could even run a crude absorption chiller if one was required - although at fairly poor efficiency). That is all; bringing in VOLTs, Prius' and the like is not a like-for-like comparison, so why do it?
Without wanting to annoy the OP, I can comment that I would like to see a BEV with a bolt-in Range-extender, that can be easily trolley'd-up to the rear of the car and located safely in place - for longer journeys. It might mean more stops for gas' as there would be less room for a tank (either integral to the car or on the R.E.), but would represent a good one-size-fits-all solution for certain commuters.
I agree. In pure BEV's, heating and cooling can be done very easily through a heat pump or a resistive heater. BEV's like the Leaf facilitate this by allowing the user to preheat or precool the car while it is still charging, thus removing that load from the battery.
Also agreed. My point is that for the foreseeable future, the issue with BEV's will be range and not a lack of heating or cooling. A range extender would be a huge increase in usability for an EV driver, and thus a device that can do both might have some advantages. Note that's not to say that a device that gives you only heat would be useless, just less useful overall.
I've often thought that a simple motorcycle-sized trailer with a small IC engine, coupled directly to the wheels of the trailer, would be a good solution to the range problem. Use the EV to get to highway speed, start the trailer engine, and let the trailer push you while you coast. If you use a little regen braking you can even recharge while you're rolling.
The trailer could power a generator, but it would be a bad place for delivering motive power, and then parking would be a nightmare.
You want to see people trying to parallel park with a trailer??
What fun.
Arthur
This is an excellent means of reducing the sapping drain of heat/cooling during journeys and is by far the simplest to build-in to a vehicle. Like many aspects of less polluting technology this also comes down to changing users mindset (think Prius divers feeling smug while monitoring there dash displays) and the days of jumping in a vehicle and whizzing off are likely to change for some (the days of cars that it made sense to sit and warm up - meaning less fogged windows as well as an engine likely to run better when warm - are even now becoming fading memories for most).
I still see a problem where BEVs are left standing, say at the out-of-town shopping centre, and returned to an hour later - the driver is not going to be keen on having a choice between having to hunt for a municipal charger to complete their journey or going back in a cold car [I live in the UK so the cooling issue is not as palpable somehow!
]. One would hope with time the number of chargers with grow exponentially, but even then the suitability of a the 'fuel' still favours NG over electric if CO2 is the main concern.Yes. The case for suitability will depend on what climate the vehicle is most commonly operated in. The worst-case scenario for straight BEV is a region with very hot summers as well as very cold winters (obviously I suppose) - Both systems have to be 'on-board' and both will sap large quantities of power, plus the cooling adds weight.
In the longer term stations with a standardised 'battery-swap' service could negate the need for range extenders, but in the meantime I can see they play their part.
If we can quickly get to batteries with at least 2.5x the energy density (for equal charging times) of today's Lithiums then some of these range issues will be removed, but there is still the question of how to get the kWh's into the pack from a household charger in, say, half an hour. Again, as implied earlier, the liquid fuel infrastructure we have built up over a century has served us well and is going to be hard to compete with - One can see why Big-Oil wants a future built around Hydrogen filling stations and why, when this really ramps up it's going to be hard to fight against!
Another problem with a trailer is it wrecks your aerodynamics.
Speaking of trailers I had mentioned this before,a possible solution for now for EV range would be a trailer with a bank of batteries that people could rent from outlets.It's said EV range is sufficient for most peoples daily driving,however those same people do go on longer trips now and then.If they could simply go and hitch up a battery trailer this would take care of their longer range issue. Maybe something like how U-haul works except battery trailers.When their car runs low on juice simply switch over to the trailers batteries.Just a thought.
I imagine since no one really knows what direction fossil fuel replacement vehicles are going to go it makes it nearly impossible to invest in the infrastructure.Like any infant technology those who bet correctly will be super rich and those that don't well,sorry.
I imagine since no one really knows what direction fossil fuel replacement vehicles are going to go it makes it nearly impossible to invest in the infrastructure.Like any infant technology those who bet correctly will be super rich and those that don't well,sorry.
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Like you, I am only speculating, but some years ago, probably in this thread, I suggested a different reasons why big oil was giving a lot of PR dollars to the "Hydrogen Future."
Namely they know well H2 is not an energy source but oil and sugar cane are. They also understand that sugar cane alcohol is already well developed and cheaper (per mile driven) than oil liquid fuel, plus the fact that the informed people know switching to a cleaner burning, renewable source is highly desirable compared to continued use of gasoline. Fact that every gram of Carbon in the exhaust of a sugar cane alcohol car was earlier REMOVED from the air gives added appeal to those concerned with the burning of fossil fuels, like oil. (When the volume of alcohol in ocean tankers, port storage tanks, distribution system, and on average 1/3 full car fuel tanks is considered, use of sugar cane alcohol fuel for cars actually makes a net slight REDUCTION in the air's CO2 not the steady increase of CO2 that oil burning makes.)
Big Oil can not creditably deny facts of the above paragraph (thought they have made considerable efforts trying to). To put it crudely: These facts scared the sh.t out of Big Oil. They concluded that their best hope was a diversion effort - strong support for the "Hydrogen Future." That could and for decades would, require oil consumption. Furthermore H2 as fuel for cars requires huge new capital investment in production and distribution AND has range limitations like battery powered cars when compared to gasoline. For these and other reasons, Big Oil knew that H2 powered cars were no threat the gasoline powered car.
They knew that tropical sugar cane alcohol was a very real and already demonstrated (in Brazil) treat, which they must divert the American public from supporting. They knew that the fact that most US cars can be converted to use pure alcohol fuel for less than the cost of conversion to natural gas fuel also must not become well known.
They have a huge lobby in Congress, the main object of which is to insure that cheaper than gasoline fuel for cars is kept out of the US.
SUMMARY: Big oil supports hydrogen as it is no threat to the dominance of oil and this support (along with money given to Congressmen) is a very effective way to divert Americans from the obvious and demonstrated advantage of tropical sugar cane alcohol as their car fuel.
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I've done this experiment with a bicycle, which (you would assume) would be much worse, since a bicycle is less stable to begin with. But it was barely noticeable.
It would indeed be tough. But if you want to drive to Vegas, and your options are attaching that trailer or renting a car, then it might be a better alternative. (Keep in mind that once you're there you can disconnect it and leave it parked somewhere.)
Any BEV that has to have a trailer attached to it all the time will be a non-starter. But a trailer to get you where you're going the few days a year you need it might be useful.
I wouldn't want to try it under all driving conditions though.
Front wheel drive is here for a reason and no design has the motive power in a trailer.
I think you underestimate how expensive this battery pack would be, so no I don't think you would just leave it around. Indeed a typical battery pack like you describe would be more expensive than a lot of cars, so no you are not going to be able to easily rent them because of the cost/liability/risk associated with that much money in a very mobile and not easily traceable platform.
Not to mention, you would have to return it to where you got it, but a lot of people don't return, so that's also a major problem.
Arthur
I like it. I would support this idea provided a few issues are dealt with.
First it does mean an agreement with the EV manufacturers to work an auxiliary power coupling into the vehicle at design stage. Unless I'm mistaken the likes of the leaf, etc come with a built-in charger socket that only allows limited Amps to the batteries and is not coupled to the motor directly. So, a second high current socket would need to be standardised for a large group of EVs.
Leading on from this, how do you deal with differing Voltages at the controller/motor (at least with the battery switching schemes that are suggested a modular approach would be workable, 37v modules for example).
However... In the UK we have a company called Streetcar, where cars and vans are located in garages around cities for on-line booking - you make your journey and drop off the car in another garage when you get there (or as near as you can!). I can envisage a similar thing with EVs, but having smaller units also that have trailers in them. If it's design as part of a fleet approach then alot of the issues of compatibility, etc go away. Of course the 'trailer' design and handling has to be pretty idiot-proof and in-comparison hire cars are not often given a gentle outing!!
Interesting points about Alcohol fuels. Can you explain how there can be a net reduction in CO2 through their use.
I am not a big fan of present large-scale alcohol fuels development, due to the risk to raising the price of food production for the poorest. However cellulotic biofuels are potentially a win-win if done well on low food-value land.
The other reason I'm not over keen on Alco-fuels is the same (not conspiratorial) reason Big-Oil is against them - they are hard to scale up because they rely on biological processes that can be poisoned, etc.
Also Oil-companies are geared up for serious chemical processing - I don't think they have the mindset to move away from that fast. This is another plus for H2 - for the foreseeable future the vast majority of it will continue be 'unlocked' from FFs - They are still simply the cheapest and largest feed-stock for hydrogen. Oil-co's already use vast amounts of the stuff in fuel processing and the move for them is natural.
Don't get me wrong I've no doubt that of the options on the table Big-Oil is going push hard for H2 - and mainly for the reasons you've said. No. 1 being it is so involved infrastructure-wise that it'll take decades.
I have heard that a number of research groups have found ways to run Fuel-cells of Diesel directly! Hard as I find this to believe (and unable to locate a link right now), if this is a reality, surely the move away from fossil-fuels would be much better for the Oil-co's if they can switch to bio-derived liquid fuels over time, but encourage cars that far offer better MPG in the interim.
Can you see a future where 1000's of small scale producers make bio-diesel, or ethonol, or higher alcohols (like Butanol) for running fuel cells on, while the Oil-companies quietly die off? ....