victorian/edwardian houses or new houses?

[Franz Heymann]

*more shrug* Maybe 60% is reached in the occasional "flagship" power station. I think it is exceptional. [snip]

Franz

[The Natural Philosopher]

That is simply not so.

With 300 mile range and potentially one hour fast charge from flat, it would be ideal for rural use and commuting.

What it won't do is 16 hour 1000 mile journeys...

Yes. That is the only issue left IMHO. But I would suspect you would not replace all teh battery - simply those cells that were below standard.

That would essentially be the major part of every 'service'

>

[IMM]

Not if the fuel is in natural gas pipelines.

The last time I looked, there were highly viable.

The UK is aiming for 25% of its power generation by wind. CHP Stirling boilers are also envisaged to fill gaps too.

??? You can get high efficient wet solar panels, but they are "very" expensive. Flat plate collectors are a lot less efficient.

You should understand how flat plate collectors work.

The economics "now" are wrong. Political will, will force it through and mass production will reduce components accordingly to a point it is feasible. It is the kick-start that is required.

Complicated? None of that is complicated at all. A lot less complicated than the current petrol IC engine/electric motor hybrids.

[IMM]

The point is that it is achievable.

[The Natural Philosopher]

Yes, but in the conxtext of hugely expensive and very new technology fuel cells, one should compare like with like.

ould it coset less to build a 60% efficint CCP or a 40% efficient fuel cell station?

Remember that the fuel cell produces DC, which needs to be chopped and flitered to feed the grid. Or a rotary conertor. All this adds to teh cost as well.

I hope we do see cheap efficient fuel cells, but they have been around snce the 60's AFAICR, and never caught on. Lithium cells have obnly really been devleoped in teh tast ten years or so, and have swept the marjket where their cots/weiht/energy profiles havce made them 'the best in class'

[Bob Hobden]

The rotary engines we have developed have all proved less efficient in practice than the old reciprocating engine (check fuel consumption) which is why only Mazda persist with them and then in only one vehicle in their range. Controlling pollution from them has been a major problem too. Fuel Cells (chemical batteries) are much more efficient at converting chemical energy to electricity than burning it in any way, be it steam powered turbines or reciprocating engines. It's why it is expected that Power Generation will follow the Fuel Cell route idc.

As far as regenerative braking is concerned he mentioned Electrically Propelled Vehicles, I've not seen a normal coach powered in such a way. Normal diesel engined coaches have had brake generators for years.

[Dave Plowman]

If you add 'potential' to that I might believe you. Non of the electric or hybrid vehicles I've read about being tested in real world conditions get near their claims of range, etc. And a one hour charge rules out lead acid batteries - so the cost of alternatives is presently prohibitive.

Well, nor will any petrol car I know about without re-fuelling. And anyone doing such a drive should have a couple of breaks anyway.

[Nick Maclaren]

Yes,indeed, it would. It is, I agree, a more realistic target than breeding flying pigs.

2) The petrol used in 300 miles by a typical modern car contains about 1 GJoule. If we assume a factor of two higher efficiency, then charging in an hour needs 140 KW. A standard domestic power circuit is rated at 7 KW. You have a factor of 20 to make up.

Dammit, a CYCLIST will expend some 20 MJoules in 300 miles. Recharging that in an hour needs 6 KW! There is NO WAY that you will design a car to be as efficient as a cyclist, despite the motor lobby propaganda.

2) Despite claims, such devices would NOT help with congestion to a detectable degree.

You need specialised facilities to charge the damn things at all, at any rate. The necessity for fancy protection mechanisms is one of the reasons that they are expensive.

Please could you take this stuff to a newsgroup (a) where people are knowledgable about this sort of thing and (b) where it is on group?

Regards, Nick Maclaren.

[IMM]

Mazda make a number of cars with rotary engines, but not sold here. The Wankle is best suited to high revving applications, hence the sports car. The RX8 is an improved rotary and of only 1300cc giving 225 HP. See if a

1300cc piston engine can deliver that. Also these engines are physically small with a very high power to weight ratio.

They are best suited to high revving applications. That is why they are used in light aircraft. The Norton motorbike rotary (which improved the design too) was sold of to two concerns. One makes it for light aircraft and the other for target drone aircraft, requiring a small heat and sound signature, which end up at the bottom of the sea.

The Russians make two rotary engines: one for a plane and the other is used (well two of them) in a helicopter, which is an ideal application for this unit.

The "Wankle" design of rotary is flawed to what is acheivable, (Wankle never invented the rotary) and far newer and improved designs are in development. Again the Russians just reversed an idea that is the reverse of the wankel. Instead of an elliptical chamber and triangular rotor, it is the reverse. The seals are in the engine block, and can be readily and super easily changed if necessary. The mixed gas input is via the rotor, which is the equivalent of injecting the mixture via the piston in a piston engine.

The Canadians have the Qusiturboine, a sort of rotary and turbine together which has received good press. Here are some web sites on concept engines and some that are in development

it needs is a big maker to adopt one of the concepts and run with it.

[Dave Plowman]

They sell rotary engined cars here.

Since its specific fuel consumption is terrible for the power output, who cares what the nominal capacity is? Apart from the likes of you, of course. You could easily achieve 173 bhp/litre from a piston engine by turbo or supercharging.

That, at least, is true.

[Franz Heymann]

I thought that the natural gas accessible to the UK was not all that much any more.

It would surprise me if they ever got that much wind power installed.

I do indeed understand how they work. The term "efficiency per square foot" is nonsense. Do you mean to tell me that if a panel has an efficiency of 1% per square foot, the installation of, say, 200 sq. ft of panel would have an efficiency of 200%?

That has been the situation for a couple of decades. It is not politics, but physics and engineering which may, or may not, get the economics right.

Actually I have my doubts about them too.

Franz

[IMM]

The North sea is still full of it and we also import the stuff from Russia.

There is a mass installation programme right now, with much off it just off-shore, out of sight and in direct line of wind.

Britain is the windiest country in Europe.

No. Just that other panels, such as Thermomax, are far higher per squ foot area than a normal cheap flat plate.

The technology and engineering is there, and it is improving by the month. That is not the problem at all. It is educating the people about the new technology and the will to push it through.

complicated

[The Natural Philosopher]

I never said you would use the domestic circuit to fast charge. The scenario was a 'fats charge' station like a petrol station where you could plug in, have a pee, have a coffee, and come back with a more or less charged car in under an hour. Typically you would NOT run the thing totally flat - more like do 200 miles and then wait 40 minutes to charge it.

I am not going to repeat the figures, but I and someone else came up independently with 9/10 hours at 20A to do the charge. That would mean essentially 200A or 50Kw to do the one hour charge. I am not sure where we differ between 50Kw and 140kW. My figures derived from taking the shaft bhp used on a normal run, and electrifying those: The figures were borne out by an actual test car that is running.

Ah. You have assumed a factor of two efficincy. I think that you should be looking at 3 or more for a start. Petrol engines are not markedly effuicient at part throttle. Transmission and ancillary sttuff (alternator and other takeoffs - colling fans etc - sap more). They are

0% efficient sitting at traffic lights whereas electric motors can be stopped altogether.

Well I dunno about cyclists. My figures were for about 50kWh (180MJ) for the 300 miles. And those figures are borne out by other test sites I found - no I haven't got them to hand because it arose in another discussion elsewhere. Might be able to dig them up if you are interested. ireckon a cyclist ambling along at 15mph might need about a horsepower.. 750W - and would take 20 hours. That's 15KWh or 55MJ? yeah. within the same range as you. For a back-of-the-envelope calculation.

If we take say 60mph as the average speed, its a 5 hour trip averaged at

10Kw, or about 15bhp. That seems eminently reasonsable for something like a Fiat Punto - 50bhp - run at on average 1/3rd throttle. I am assuming better than 90% conversion efficviency, because that is what a decent electric motor, cells and controller can do. These are not fairy land figures.

No one said they would. what we are aiming for is almost zero pollution at teh point-of-transport, and utilkisation of an existing electricity infrastructure, especailly use of off peak electricity, which allows for better efficiency of generation anyway.

Congestion can only be reduced by either dramatically raising speed limits, or taking cars actually off the road.

Nothing too fancy is needed. A simple voltage and temperature monitor is all that is required.

Currently the ones being developed for model use are about 30% of cell cost - a few dollars only. How this would scale with larger cells is unknown. Its the last area to investigate.

Well you seem to think YOU are, and so does IMM. AND I think its is interesting enough to stay here until it dies of boredom.

Its no more YOUR group than it is mine. Its marginally nearer on topic than 'britney spears nude'

[Nick Smith]

What ??? I can't imagine a human being able to develop a horsepower for very long at all - more like 100 or 200 watts and even that would not be sustainable for long. So how does the average "regular" cyclist ride a bike for an hour or so at 15 mph covering 15 miles ?

Nick

[The Natural Philosopher]

Not so. Things have really moved on in the last year or so. To the point where there is at least one company brave enough to have built a lithium polymer powered test car and be offering cell packs for sale. They have repacakged the biggest they could find with safety circuitry and the tests they came up with were close enough to my predictions for me to feel they were not avaiting porcines.

Price is still an issue - the sort of stuff I buy retails at $3 per watt hour, so 50kWh is $150,000

Thst for torch battery sized stuff. That represents a sort of 'it won't cost more than that' level. A hand built racing engine costs thet much as well, and no one says that because a Cosworth F1 engine is 100 grand, thats waht a Ka should cost as well..

No, but the problem is the one hour minimum to completely refill its 'tank'

Here are some links

one is already 9 years old but predicts todays performamnce figures

the record holding electric car for teh Pikes |Peak run

is a company that can acatually supply 35kWh batteries for cars...tho there is a whiff of bovine excrement about his one. some data from a 1998 conference that pretty much says the same thing I have been saying. I found the one site I was looking for

This is a mean machine.

Enjoy :-)

[The Natural Philosopher]

Its also very arguable what the capacity of a wankel actually is.

F1 engines exceed 200bhp per litre with no forced charging. Top[ fuel drag cars are doing about 1000 bhp per liter with full nitro and supercharging. Well for 5 seconds anyway :-)

Mmmm. I checked out some model plane electric motors. About a kilowatt and 3/4 pound, so about 2bhp per pound. 200 brake horsepower for 100lb weight anyone? and no gearbox or clutch? No wonder that electric Lithium car at AC propulsion is gettin 0-60 times in under 4 seconds, and a 300 mile range...

They beat the fuel cell cars on everything at the tests.

>

[The Natural Philosopher]

Mmm. Bits of my old cedar shingled roof appeared to consist of

- and old broom handle nailed and lashed to a rotted bit of

- pine tree sawn into quarters. Quite a bit of this and

- an actual branch from an oak tree.

- and lots of other wobbly bits of timber. Not a sqare sawn bit in the place except where some 'modern' bodging had been done with some 4x2.

In s. africa where thatch is often used and wood is scarce they tend to use round poles tapering from 4" diameter and finishing at ofetn little more than 2" for a 'rondavel"

They stay up and support the thatch just fine :-)

I am not decryng building regs, merely pointin out

that rooves are there to keep the rain off: A large tent does no better.

The timbers used are really all about the weight of the cladding. In my case the imminent demise of the shingles was, with the leaking of a tiled section and the impossibility of re-roofing without using heavier rafters, that meant totally popping what they rested on etc etc, that led me to fianally pull it down.

However, up till then it had been totally fine :-)

[RichardS]

There are two problems with elecric motor vehicles that would have to be overcome to make them viable.

First problem would be that they really need some kind of backup power. If a conventional fuel vehicle (or indeed any fuel that can be quickly recharged) runs out of or low on fuel then it is a quick and simple job to put more in the tank. A battery powered vehicle would need some considerable time recharging - either at the side of the road or at a recharge point/"fuel" station. Forget to put the thing on charge last night? You're stuck in the morning. Power cut? Ditto. The occasional long journey? Forget it.

Second problem is one of recharge logistics.

Battery vehicles would represent a considerable advantage in towns and cities. Quiet and pollution free at the point of use.

However, the majority of people living within large cities and towns do not have designated parking spaces, and most of it is on-street parking. Pavements would have to be dug up and publically accessible chargeing points installed to be able to recharge such a vehicle, along with a suitable payment mechanism. I can't see the LA taking too kindly to me stringing a cable across the pavement to my house! Even in areas with controlled parking zones there is no right to be able to park outside one's house, so the price of someone parking in "my" space, abandoning a car or even leaving a skip would be complete immobility for me. Visitors? Hmmm.

I'd have a battery powered vehicle at a sensible price and with decent performance/range like a shot. But until these problems are solved, then it's not viable.

-- Richard Sampson

email me at richard at olifant d-ot co do-t uk

[RichardS]

atmospheric

Andy, Jaques, Mary, Nick,

many thanks - moss and lichen stuff was interesting.

I didn't quite expect the thread to wander off onto heated discussion about pollution and vehicle motive power, but you never can tell with usenet (to paraphrase Winnie the Poo). Sorry about that!

-- Richard Sampson

email me at richard at olifant d-ot co do-t uk

[Nick Maclaren]

Followups set somewhere more relevant.

In article snipped-for-privacy@b.c, The Natural Philosopher snipped-for-privacy@b.c writes: |> |> >>>An electric car is only suitable for city use and will do nothing for |> >>>congestion. |> >>>

|> >>That is simply not so. |> >>

|> >>With 300 mile range and potentially one hour fast charge from flat, it |> >>would be ideal for rural use and commuting. |> > |> > Yes,indeed, it would. It is, I agree, a more realistic target than |> > breeding flying pigs. |> > |> > 2) The petrol used in 300 miles by a typical modern car contains |> > about 1 GJoule. If we assume a factor of two higher efficiency, then |> > charging in an hour needs 140 KW. A standard domestic power circuit |> > is rated at 7 KW. You have a factor of 20 to make up. |> |> I never said you would use the domestic circuit to fast charge. The |> scenario was a 'fats charge' station like a petrol station where you |> could plug in, have a pee, have a coffee, and come back with a more or |> less charged car in under an hour. Typically you would NOT run the thing |> totally flat - more like do 200 miles and then wait 40 minutes to charge it.

Well, excluding the minor detail that taking an hour to 'fill up' where it currently takes 5 minutes is not something that I should want to do, using a 200 A circuit safely or even practically isn't like using a 13 A one. Even in industry, the maximum plug that is used just like a domestic 13 A one is rated at 32 A.

Inter alia, contact corrosion, condensation and so on are BAD NEWS at 200 A.

|> Ah. You have assumed a factor of two efficincy. I think that you should |> be looking at 3 or more for a start. Petrol engines are not markedly |> effuicient at part throttle. Transmission and ancillary sttuff |> (alternator and other takeoffs - colling fans etc - sap more). They are |> 0% efficient sitting at traffic lights whereas electric motors can be |> stopped altogether.

I was estimating on the basis of distance driving. 50 KW is too low, except for the smallest runabout, which would not meet most people's requirements. 100 KW is more plausible, even given your factor of 3.

In article <1cGMb.422$ [e-mail]>, "Nick Smith" [e-mail]> writes: |> > >

|> > > Dammit, a CYCLIST will expend some 20 MJ in 300 miles. Recharging |> > > that in an hour needs 6 KW! There is NO WAY that you will design a car |> > > to be as efficient as a cyclist, despite the motor lobby propaganda. |> >

|> > Well I dunno about cyclists. My figures were for about 50kWh (180MJ) for |> > the 300 miles. And those figures are borne out by other test sites I |> > found - no I haven't got them to hand because it arose in another |> > discussion elsewhere. Might be able to dig them up if you are |> > interested. ireckon a cyclist ambling along at 15mph might need about a |> > horsepower.. 750W - and would take 20 hours. That's 15KWh or 55MJ? yeah. |> > within the same range as you. For a back-of-the-envelope calculation. |> |> What ??? I can't imagine a human being able to develop a horsepower |> for very long at all - more like 100 or 200 watts and even that would not be |> sustainable for long. So how does the average "regular" cyclist ride a bike for |> an hour or so at 15 mph covering 15 miles ?

At 200 W.

Regards, Nick Maclaren.