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Posted
11 hours ago, BrendAn said:

I can't see solar being able to propel a loaded vehicle with a family in it very far at a time. The electric vehicles that have crossed the Nullarbor are feather weight single seat contraptions that pick the best time of year to do it. . Some days you can have a 30 kn headwind .other times it is overcast and raining for days on end. That is the challenge I think. What do the solar cells do in those conditions. 

The energy flux of sunlight reaching the surface is about 1kW per m2 and assuming that you have 20% solar panels that about 200W/m2

Compare this will a 200kW subaru WRX and you can see that there's an issue. A car moving at 100km/h requires about 20kW on flat ground so you need an area of about 100m2 ie 10x10m to cruise on flat ground, at midday.... It might be a bit difficult to fit in the garage.

If you had a  local battery with 90% (so make the panel 120m2 and less than optimal charging times) charging efficiency you need to park for an hour at ok generation times (9am-3pm)  for every hours travel.

 

Most houses with solar don't have panels of this area or mounted at optimal angles. But over a number of days house solar will charge a car.

 

Solar and wind are diffuse, that's why sailing boats are slow compared to motor boats.

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Posted
1 hour ago, Ian said:

Most houses with solar don't have panels of this area or mounted at optimal angles…

Mine does. We built in the early 80’s, applying simple design ideas widely promoted in that post-energy crisis era. The result is a passive solar house that uses a tiny fraction as much energy as our neighbours. I’ve spent forty years and quite a bit of money promoting these simple design ideas to people who plan on building…with absolutely ZERO SUCCESS!

 

It’s utterly frustrating how many visitors have admired our solar home and been impressed by it’s performance…and then mortgaged their life to have a standard, suburban brick veneerial plonked down on their block, facing the street, no matter where the bluddy sun tracks!

Much later, some complain that the searing summer sun comes into their house.

 

1 hour ago, Ian said:

Solar and wind are diffuse, that's why sailing boats are slow compared to motor boats.

Old-fashioned thinking; not long ago critics claimed steam trains could never go faster than a horse.

Wind-powered craft Can be faster

https://www.autoevolution.com/news/sailing-champion-to-break-the-wind-powered-land-speed-record-of-126-mph-with-a-new-craft-182227.html

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Posted
12 hours ago, Old Koreelah said:

Old-fashioned thinking; not long ago critics claimed steam trains could never go faster than a horse.

Wind-powered craft Can be faster

Yes I used to sail cats and was wondering if anyone would be pedantic enough to call some of the high speed records 😉

 

How about "In the majority of situations, powered craft will be significantly faster than wind and solar craft". This allows for world speed records on water, air, ice and land.

You missed the wind powered dynamic soaring speeds of 548 miles an hour on a very good day.

 

 

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Posted

I couldn't see it at all till I went full screen. Wow that thing is fast. The G forces must be incredible.

Posted (edited)
9 hours ago, kgwilson said:

I couldn't see it at all till I went full screen. Wow that thing is fast. The G forces must be incredible.

Below is another good video on the theory and story behind the dynamic soaring record which is interesting but a little more esoteric. Who would have thought supersonic airflow would cause a glider to crash. I just like the sound of it going through the air. In it he says that the G force meter topped out at 120G

 

It isn't like an ordinary glider weight isn't so much of an issue but strength so it can withstand the G forces. I'm surprised that they don't crash more as it's moving so fast.

 

 

 

Edited by Ian
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Posted

Fascinating. I'd always known about Albatrosses dynamic soaring and that they have tracked Wandering Albatrosses circumnavigating the world in the Southern latitudes. This takes the phenomenon to a whole new level.

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Posted

In relation to our discussion about EV charging in Multi Unit complexes, I asked the opinion of a professional fire services engineer.

 

He said:

“It’s a huge problem, just cannot happen. This is the problem with politicians and ignorant narrative.

 

They are already making EV chargers compulsory in Class 2 (residential apartment buildings) in underground car parks which is a major fire risk problem and many other issues.

 

The major issue these people haven’t understood is there is no electrical power capacity in these existing buildings to charge these cars.

 

Charging uses a huge amount of kilowatts.

 

When people come home and plug their cars in it is typically at peak power demand time of the day.

 

Unless they put delay start timers on these chargers it will cause an instant power overload on the electrical infrastructure in the building, but timers still don’t solve the problem.

 

Even with timers, the power demand will be huge and the maximum demand calculations that are used to calculate capacity in main switchboards, consumer power mains, sub main risers etc. will be woefully inadequate when you start to add EV charging power demand.

 

The second problem is that there are no individual power circuits in basement car parks that come from each unit’s switchboard so that the power can be charged against each consumers power usage.

 

Even if there was a 10-amp power point, that is woefully inadequate for car charging unless you are prepared to wait 10 hours.

 

The third problem is if all the apartment building stock wanted to install power for EV charging, the street and locality power distribution infrastructure (poles, wires, substations etc) does NOT have the capacity.

 

The fourth problem is there is no baseline power in the system despite what the dreamers say."

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Posted
28 minutes ago, turboplanner said:

“It’s a huge problem, just cannot happen. This is the problem with politicians and ignorant narrative.

 

 

If this is true (and it isn't) then it will very soo become evident. 

 

32 minutes ago, turboplanner said:

The major issue these people haven’t understood is there is no electrical power capacity in these existing buildings to charge these cars.

 

How does it work in Norway?  Yes Norway has a lot of Hydro however the problems with their existing electrical distribution system must be somewhat similar to ours.    The number of EVs in Norway has increased massively in the last few years. Presumably they have not rebuilt their whole network of poles and wires in such a short time. 

 

 

43 minutes ago, turboplanner said:

Unless they put delay start timers on these chargers it will cause an instant power overload on the electrical infrastructure in the building, but timers still don’t solve the problem.

 

We are not talking about crude timers on chargers. It is a case of chargers that talk to the grid.    

 

 

Are buildings and carparks burning down in Norway?

 

https://risefr.no/media/publikasjoner/upload/2020/report-2020-30-charging-of-electric-cars-in-parking-garages.pdf

 

 

1 hour ago, turboplanner said:

The second problem is that there are no individual power circuits in basement car parks that come from each unit’s switchboard so that the power can be charged against each consumers power usage.

A charger connected to a common source is not really different from any other public charger.   The charging is paid for using an app. and a third party such as Vista Vista Charge. This is being done now.  https://vpt.com.au/blog/guide-to-smart-ev-charging-in-strata-car-parking/

 

 

 

 

No one is saying that we could go 100% EV tomorrow.   This is for many reasons not possible. The gird of today evolves to suit our needs.   

 

Most of the network problems you have pointed out should also apply to other countries that are ahead of us with EV adoption.   We are not on the leading edge of change in this country.  

 

I am sure I wont convince you of anything.   You say it "can't work" if you are correct the next few years will support your view.  EVs will begin to disappear overseas and here the adoption will slow and stop.  I suspect that EV adoption will continue and increase. I suspect new houses apartments and buildings will built with EV charging in mind. I suspect the grid will evolve along with this change to support and also utilize EV batteries. 

Time will tell.  We should revisit this subject every few years and see which way the trend is going.   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Posted
1 hour ago, turboplanner said:

In relation to our discussion about EV charging in Multi Unit complexes, I asked the opinion of a professional fire services engineer.

 

He said:

“It’s a huge problem, just cannot happen. This is the problem with politicians and ignorant narrative.

I don't really rate your fire services engineer. This is a henny penny type argument, it is a basic infrastructure problem and it's an easy problem to solve from a design perspective, electrical engineers design standard circuit types to be deployed in these environments which are specified in Australian Standards, if a standard can't found it should designed by a qualified engineer. For example in some environments low smoke flame retardant non-toxic insulation TPE/TPU is mandated (specified in Australian Standard). Sounds like it would be suitable for deployment in an underground car park with limited insulation. (We did have a discussion earlier of whether there's a difference between a university qualified engineer with a BEng or someone who has put the word engineer in their title)

 

The technology to solve the peak load problem exists and has been in existence for years and yes even Governments know about it. Essentially it's a modern version of off peak power but smart enough to tell the difference between I need the car charged now or I need the car charged by 9am tomorrow.

https://www.smartgrid.gov/the_smart_grid/electric_vehicles.html

Unsurprisingly power companies are also  looking at using your car batteries to stabilise the grid https://www.agl.com.au/residential/energy/electric-vehicles/smart-charging-trial, I wouldn't participate in this unless there is a very large payback, your car batteries wear out.

 

 

 

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Posted
52 minutes ago, octave said:

I am sure I wont convince you of anything.   You say it "can't work" if you are correct the next few years will support your view. 

Octave sometimes it pays to read a post before you start typing.

I posted, in quotation marks information I received from an Industry professional for the benefit of people interested in multi unit complexes and to a degree street charging.

 

He has the qualifications to inspect the buildings and do the calculations, and is entitled to his, professional, opinions.

Posted

It might have been better to talk to an electrical engineer?

 

Solutions to these problems already exist:

1) Most of the time, vehicles plugged in won't actually be charging because charging from empty is rare.

2) Chargers can distribute available power depending on how many cars are being charged. e.g. if your charger has 20KW available, 1 car can get 20KW, 2 cars 10KW each, 10 cars 2KW each etc.

Posted
30 minutes ago, Ian said:

I don't really rate your fire services engineer. This is a henny penny type argument, it is a basic infrastructure problem and it's an easy problem to solve from a design perspective, electrical engineers design standard circuit types to be deployed in these environments which are specified in Australian Standards, if a standard can't found it should designed by a qualified engineer. For example in some environments low smoke flame retardant non-toxic insulation TPE/TPU is mandated (specified in Australian Standard). Sounds like it would be suitable for deployment in an underground car park with limited insulation. (We did have a discussion earlier of whether there's a difference between a university qualified engineer with a BEng or someone who has put the word engineer in their title)

 

The technology to solve the peak load problem exists and has been in existence for years and yes even Governments know about it. Essentially it's a modern version of off peak power but smart enough to tell the difference between I need the car charged now or I need the car charged by 9am tomorrow.

https://www.smartgrid.gov/the_smart_grid/electric_vehicles.html

Unsurprisingly power companies are also  looking at using your car batteries to stabilise the grid https://www.agl.com.au/residential/energy/electric-vehicles/smart-charging-trial, I wouldn't participate in this unless there is a very large payback, your car batteries wear out.

 

 

 

I haven't spent the time to check how many of these developments have occurred in Melbourne but let's say half a million, What we were talking about was now, the ones which have been built.

Yes, the next one coming up for the design phase could have the changes you suggest, but if one of those half million families decides to buy an EV now, it's ind the nearest commercial charging point.

 

The peak power he's talking about is the coal plant fully fired up.

 

Have you been able to get any off peak electricity? I tried about 8 years ago, bought a hot water system with off peak charging timer. The electrician was forst told it must be wired separately to a se[parate switchboard meter, then when he'd done that, the issue was kicked upstairs and the company said they no longer offered off-peak rates. The renewables have been undercutting the coal-fired in this low demand area to the point where coal fired has to charge more to recover costs.

 

I wouldn't worry about the BE; this guy has serious industry credentials, but he didn't ask me to hire him. We all should be talking about kWH so we know we are talking about the same load and same capacity.

 

Posted
4 minutes ago, aro said:

1) Most of the time, vehicles plugged in won't actually be charging because charging from empty is rare.

2) Chargers can distribute available power depending on how many cars are being charged. e.g. if your charger has 20KW available, 1 car can get 20KW, 2 cars 10KW each, 10 cars 2KW each etc.

What do they plug into? Remember he was talking about multi-unit - 100 to 200 units in maybe a 4 story cluster with no plags in the car park for car owners.

Posted
13 minutes ago, turboplanner said:

Octave sometimes it pays to read a post before you start typing.

I posted, in quotation marks information I received from an Industry professional for the benefit of people interested in multi unit complexes and to a degree street charging.

 

He has the qualifications to inspect the buildings and do the calculations, and is entitled to his, professional, opinions.

 

Turbs I do a lot of reading even past the headlines.   Saying a professional has given his or her opinion is a little vague.       I am more than happy to read any factual articles you care to post and I will even read past the headloines.

Posted (edited)

It doesn't matter whose opinion you get because it will be tainted with that persons personal beliefs and prejudices. It is more valid to get a written statement or thesis  from someone on a specific subject and have that peer reviewed. Then you can allocate some credence to the information provided. So a "Professional" opinion is just an opinion and in this case from a Fire Services Engineer about charging electric vehicles in a multi unit complex. When was electric vehicle charging included as part of fire services engineers qualifications?

Edited by kgwilson
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