Charging with 220V 13A socket in Hong Kong

[sonywong]

If I charge the Model S with 13A socket in HK, do I get just 2.86KW per hour? So it would take almost 30 hours to fully charge the 85kwh battery?

Anyone knows?

[montgom626]

yep about

[sonywong]

yep about

thanks, lucky I don't drive over 50km (around 30 miles) a day.

[moarfish]

How do you guys solve the charging problem?
I do not have a charging car park in my apartment. I work in Kwun Tong so I think I would to charge in Kwun Tong Plaza during the working hours. However, there is only one charging car park there. It is currently always empty but I doubt if it still available after those 200 Model S arrived.
In Hong Kong, there are only 1000 charging station and the current EVs already taken 3xx of them, not counting the coming 200 Model S.
I think one day I have to arrive work very very early to compete for one charing station in Kwun Tong area.

[markwj]

If I charge the Model S with 13A socket in HK, do I get just 2.86KW per hour? So it would take almost 30 hours to fully charge the 85kwh battery?

Anyone knows?

You can work this out as watts = volts x amps. So, 220V x 13A = 2.86kW. But, there are charging inefficiencies (particularly cooling for the batteries and waste in the charging process) that can be around 50%. A safer estimate would be 2kW per hour. Charging overnight (12 hours) should top-up your car nicely, but you'll need 40+ hours to fill from completely empty to completely full.

My opinion (and some say, general consensus) is that charging at 220V 13A is fine for overnight and long-term charging, but not much use for shopping centre visits (of just a couple of hours).

I did some tests on this back in 2011, with the Tesla Roadster:

Charging in High Temperature environments 13A vs 32A vs 70A: cost of air conditioning

and my conclusions were:

Attachment 2660

and you can see Tom Saxton's blog on this (at North American temperatures) at:

Tesla Roadster Charging Rates and Efficiency - Tom Saxton's Blog

How do you guys solve the charging problem?
I do not have a charging car park in my apartment. I work in Kwun Tong so I think I would to charge in Kwun Tong Plaza during the working hours. However, there is only one charging car park there. It is currently always empty but I doubt if it still available after those 200 Model S arrived.
In Hong Kong, there are only 1000 charging station and the current EVs already taken 3xx of them, not counting the coming 200 Model S.
I think one day I have to arrive work very very early to compete for one charing station in Kwun Tong area.

Those 1,000 charging points are empty (or full of ICE cars) the vast majority of the time. Don't worry about competition for them (at the moment, or after 200 Model S), although 1 spot in Kwun Tong Plaza is concerning.

For the latest status, see: Open Charge Map - Web App - a search for "Kwun Tong" shows 11 buildings. Best is the government car parks - most have 20 to 30 charging points.

The absolute best is to charge at your home car park, overnight. This has been discussed here:

Home EV charging in apartment block complex carparks

Very little progress towards helping owners with this so far, though.

Regards, Mark.

[sonywong]

Thank you Mark, very useful info. I didn't know about the energy wasted in cooling down the battery while charging.

There is a 13A socket in my apartment's parking space and I am gonna ask the property management to see if I can use it to charge my car. I am still thinking whether I should just use it without asking them... (if I don't ask, they may not notice but this is stealing; If I asked they probably won't let me do that coz it may take sometimes to let them know it is safe to charge a EV in the car park) If they don't let me do that, I will work in Sheung Wan/Central/Admiralty area later this year and I will park and charge in one of those government car parks.

You can work this out as watts = volts x amps. So, 220V x 13A = 2.86kW. But, there are charging inefficiencies (particularly cooling for the batteries and waste in the charging process) that can be around 50%. A safer estimate would be 2kW per hour. Charging overnight (12 hours) should top-up your car nicely, but you'll need 40+ hours to fill from completely empty to completely full.

My opinion (and some say, general consensus) is that charging at 220V 13A is fine for overnight and long-term charging, but not much use for shopping centre visits (of just a couple of hours).

I did some tests on this back in 2011, with the Tesla Roadster:

Charging in High Temperature environments 13A vs 32A vs 70A: cost of air conditioning

and my conclusions were:

Attachment 2660

and you can see Tom Saxton's blog on this (at North American temperatures) at:

Tesla Roadster Charging Rates and Efficiency - Tom Saxton's Blog



Those 1,000 charging points are empty (or full of ICE cars) the vast majority of the time. Don't worry about competition for them (at the moment, or after 200 Model S), although 1 spot in Kwun Tong Plaza is concerning.

For the latest status, see: Open Charge Map - Web App - a search for "Kwun Tong" shows 11 buildings. Best is the government car parks - most have 20 to 30 charging points.

The absolute best is to charge at your home car park, overnight. This has been discussed here:

Home EV charging in apartment block complex carparks

Very little progress towards helping owners with this so far, though.

Regards, Mark.