CHOICE membership

Electric and Alternative Vehicle Fuels


#41

I wish I were… change can be an arduous and painful journey but I sort of agree… with enough marketing money anything is possible :wink:


#42

An interesting article but it was also written back in 2006, long before hydrogen powered cars went into production.


#43

That study is 12 years old… lot’s more information out now.
What I was talking about was experience… we had a scooter using a battery and one with a Hydrogen Fuel Cell (HFC), the HFC provided both more power and longer high power.


#44

Ummm …
In 1966, General Motors developed the first fuel cell road vehicle, …

What information? Where? What is the full-cycle efficiency?


#45

Check out the International Journal of Hydrogen Energy

This paper may be of interest re the efficiencies


They are paid papers so you’d have to look through but there are a lot of changes since that article you pointed to.

The US Govt are also seriously investigating this arena… https://www.hydrogen.energy.gov


#46

Yes, there were previous hydrogen powered vehicles but they were neither practical nor mass-produced until the last few years.

Way back in ancient times when I went to school, we were the first grade 8 class after the old scholarship was cancelled, and the last class after that to study chemistry and physics before they were replaced by science and biology under the new curriculum.

We were actually taught that an atom was the smallest thing that could survive by itself and that the smallest particle was an electron.

I don’t believe that is quite correct anymore.

Apart from Albert Einstein’s theories, nothing much in science is set in stone.

The very fact that hydrogen powered vehicles are now being mass produced is testament to the viability of the science.

And the CSIRO statement yesterday advising that hydrogen powered cars will travel around twice as far for around half the cost of their petrol equivalents, and be refuelled in the same timeframe, will no doubt contribute to their uptake.


#47

In theory this may be possible if one has an enormous boot or maybe a ute/small truck, but it is unlikely to every eventuate.

To charge say a 60kWh battery, which happens to be the smallest Telsa uses in its vehicles, one would need a system which can provide 60kW rapidly.

Even if solar was 100% efficient, along with power tranformation and charging, one would need about 60m2 of PV cells for a one hour charge. If say one can does a full standand rate charge (about 10 hours), one would still need 6m2 of panels assuming 100% efficiency.

100% efficiency will never be achievable, even in controlled optimum conditions. I have read that around 20% may be the maximum efficiency for PV and charging losses could be in the order of 5-10%.

Assuming these realistic maximum efficiency rates, then one would need about 30-35m2 of PV panels to allow the car batter to charge in 10 hours (and assuming perfect weather and even sun intensity from morning to dusk).

30-35m2 of panels (and power transformation) is significant weight which would impact on the range of the vehicle which battery is being charged…meaning even more stops to solar recharge. These panels would slso take significant volume within the vehicle as well and also be challenging to set up especually on the side of the road at the back of Burke. I personally wouldn’t want to spend possibly a hour of two in 40°C heat setting it up and then waiting in the same heat on the side of the road for the charge to be completed.

I personally beleive that in the future battery vehicles will be mainly suited to urban and short trip locations. For longer distances, things like biodiesel (which has its own challenges) and hydrogn will be the main solutions when fossil fuels become uneconomic to use as a transport fuel.

Another option which is very expensive is a trolley bus type system above all highways etc which provided connected mains power to electric vehicles. The costs to do this would be a huge economic burden and itself has its own challenges.


#48

You’ll need to quote and link to the figures upon which you rely. Remember, we’re talking full-cycle efficiency, not just the fuel cells. Adding the ammonia cycle will reduce full-cycle efficiency.

It strikes me that you’re saying “efficiency”, but talking more about energy density.

From what I see, efficiency might have improved to 33% (without the ammonia complication).

In the old days, horses were the primary power source for transportation. Horses tired quickly, so commercial vehicles needed to regularly change teams. For that reason, changing stations were set up along main routes. Batteries last far longer than horses, so we’d need fewer stations to swap them over. Probably no more than the existing petrol stations. Hydrogen or liquid fuels are not the only solution, and probably not the most efficient one.

Funny you should mention that. Newcastle is getting its trams back. They’re wireless.


#49

The science always comes before the economic realisation or failure. rIp beta Video tapes.

Being good scientists is it correct to assume the cost of the hydrogen at the bowser includes the retailers margin and federal fuel excise tax?


#50

hmm, ‘burnt instantly’ … aka an explosion! Currently most Hydrogen comes from fossil fuels, producing it from water is quite inefficient.

re the various comments about the time taken to charge a battery:


#51

Re ultra fast EV chargers, while it might appear to be a huge step forward it neglects human nature as presented. A 5 minutes charge might fly, but think about the queues and ‘servo rage’ with 10-15 minute ones, and thus implications for ‘servo’ design. Also, what loads will these chargers put on the local power reticulation systems when they are deployed in volume? Will they have to be upgraded? What about more rural power distribution systems?

All honest questions and I suspect you will have some interesting thoughts if not outright answers. :slight_smile:


#52

If the time factor proves to be a substantial problem, then swappable batteries might be a solution. Roll over the pit (automated), battery out, new one in (automated). Electronic payment. Away in 30 seconds. Of course, that would mean battery standardisation. Government might actually have to do something. :scream:

I’ve seen mention of servo designs that incorporate substantial storage of their own. The batteries are charged at the cheapest rates and from local solar panels. Peak power drain never goes near the grid.

As an aside, the servos can participate in the demand management market, bidding in reserve capacity and managing demand for profit.

I imagine most charging will be domestic. That is, at home.


#53

Most charging stations will have their own battery to deliver high power, probably well beyond the capability of the local grid in many cases. Many will probably have their own solar array as well, which will charge all day to reduce reliance on charging the station from the grid.
Re queue rage, arent EV drivers above that sort of behaviour? :slight_smile: During the various petrol shortages I’ve seen over the years, people have been well behaved in queues, although I haven’t witnessed what goes on in the city. Maybe country people are more relaxed :slight_smile:

Battery swapping has certainly been discussed for years, no doubt due to the earlier slow charging times, but current models aren’t using that system.


#54

Of course they are.
The cars will all be driverless. AI has no anger.

The laws of robotics say so. Just before the one that denies the existance of program errors and corrupt data.


#55

Interesting that 80% can only be achieved using rapid charge technologies due to (excessive) heatbuild up in the battery.

I suppose the other concern is reduced battery life/capacity through these high speed charging as well. I suppose one has to consider whether time is worth more than shorter battery lives…in a modern world time is possibly more important?


#56

Some of the arguments being put forward on this topic in support of electric vehicles over hydrogen powered vehicles are reminiscent of those tried by the Stanley Motor Carriage Company to promote their Stanley Steamer vehicles over internal combustion vehicles as per the extract from an article on Wikipedia posted below.

“Obsolescence
During the mid to late 1910s, the fuel efficiency and power delivery of internal combustion engines improved dramatically and using an electric starter instead of the crank, which had been notorious for injuring its operators, led to the rise of the gasoline-powered automobile, which also was much cheaper. The Stanley company produced a series of advertising campaigns trying to recover the car-buying public away from the “internal explosion engine,” but it was unsuccessful. Their advertising slogan was, “Power – Correctly Generated, Correctly Controlled, Correctly Applied to the Rear Axle.” These were early examples of the fear, uncertainty and doubt advertising campaign, since their aim was not to convince buyers of the advantages of the Stanley Steamer but to suggest that internal combustion automobiles could explode.”

At least they had one advantage as they were not stolen. What thief would want to have to wait 20 minutes or so for the required steam pressure to be achieved.


#57

Which perhaps shows that the market judges it not a problem.

What time? How much charging will be done anywhere but at home, workplace, parking lot or at some other time when the vehicle is not in active use? We seem to be stuck with an outmoded paradigm:
Drive someplace, fill up, drive a bit more, fill up again.
The world changes when the vehicle can be “refueled” anywhere there’s a power outlet.

As the article linked above points out:

350 kW charging would allow a 100 kWh EV battery to charge to 80% in less than 15 minutes. That equates to adding another 400 km worth of charge in the time it takes to drink a coffee. (Which, after travelling 450- 500 km if beginning on a full charge, you should be stopping for longer than that anyway!).

Is there an issue? The market seems to be saying there isn’t.

An associated point:
If most recharging won’t be done at service stations, what is the future role of service stations? How many will be needed?


#58

It’s possible that what we now see in the future shape and design of a motor vehicle will also change dramatically. Any change in function and use may render our current visions unreliable.

Early horseless vehicle developments replicated horse and buggy visions. They resemblance to modern vehicles is no more than a need for 2 or more wheels.

If the drivers of climate change and lessening planetary resources are great enough:
The notion of an overweight inefficient vehicle weighing close to 1.5 tonnes with a single 80kg passenger will be seen as unsustainable, hydrogen, batteries or coal
The notion we all need to drive to work is already under challenge.
Do we all need a vehicle that is multipurpose and while used daily for a one person commute of an hour, it also needs to seat 6 and tow 3.5tonnes of caravan 2,000km twice each year to go fishing?

This suggests that by changing how we do what we do we can save much more without having to invent new things that perpetuate the same poor and inefficient behaviours.

Who will be first?


#59

Actually, the often touted excessive heat build up is not really the main reason that ‘80% in xx minutes’ is so often talked about. Yes, super fast charging is likely to shorten battery life a bit, but by how much is influenced by a number of different factors - there will probably be clauses in the warranty about fast charging rates.

The main factor in only being able to get to 80% quickly, is that if you try to maintain the high charge rate, battery voltage will rise to dangerous levels. All batteries have a maximum operating voltage, which must be observed if you want to have a long battery life, and in the case of some high energy density Lithium batteries, avoid fire and explosion!

Here’s a graph showing my LiFePO4 battery charging yesterday, black line is voltage, scale on the right side. Voltage increases as the PV output increases (with a charging station you have full power immediately), until what’s known as the absorb voltage is reached, and from them on it is essentially constant voltage with reduced current until the charging current falls to a low level, generally somewhere around 5-15Amps, at which point the battery is charged. After that it goes to floating, which I have set so that the battery very slowly discharges, with the PV system essentially meeting all loads until the sun is gone, a bit before 4pm at this time of year.
Different Li chemistry used in EVs means they can charge at a higher voltage and current, so 80%State Of Charge can be reached at essentially full charging current, where I have to taper it back well before 80%SOC, at around 70% in this case, from about 8:30am

Orange line is the state of charge, green the PV output, red the net charge or discharge for the battery, all using the left hand scale.

click on the image to see it clearly.


#60

Something about unsustainable makes me think it’s been that way for a long time, it needs to become unacceptable.

Strange how a lot of us spend a good part of the first 16 years of our lives riding a bike (some like @gordon never stopped) yet when we get the ticket we drive. All of a sudden we can’t balance? I use 4 wheels for carrying loads/shopping/multi-person trips - 2 for everything else, including the commute, powered but still 2 … and there’s some interesting 2 wheel alternate fuel vehicles emerging as well …