EV charge times

lyledunn: 
 

Apparently from September 2021 charge points placed on the U.K. market are required to be factory set not to charge during peak times, 8-11am and 4-10pm. Although the parameter can be altered by the user, it is a recognition that things are getting tight.

Apart from the demand on the grid. It's a grid lock with traffic in some areas at peak times and electric vehicles will not alleviate that problem. There are simply too many vehicles on the roads. Also residential areas, have escalating parking problems with vehicles being parked on pavements and other areas, causing a hazard. For starters only, I think it will eventually become law that single occupants in a driven car unless a taxi etc., will be made taboo. 

Further, blame seems to concentrate on live stock etc. as a source of pollution, but the human animal farts and belches as well, with little being said about the number of people and the birth rate. One could also accept the fact, that we are all merely tenants in an ageing world with borrowed time.

Jaymack      

davezawadi (David Stone): 
 

There is a huge misunderstanding going on here. The real charging rate is controlled by the vehicle, not the charge point. The range of charge rate options depends on the vehicle and they are not all the same and some are quite simple. Reducing the mains voltage for example does not reduce the charge power, it just increases the current. Charge points do provide communication with the vehicle, but this is not usually on a completely “sliding scale” as this makes the charger (in the vehicle) much more complex.

 

It's not that simple, as the charger also tells the vehicle how much power it is allowed to draw.  Otherwise you'd get cars trying to charge at 7.2kW through a “granny lead” plugged into a 13A socket.

Vehicle charging is most definitely defined in terms of current even if it's presented to the user as power. The charger signals to the car a current it is allowed to draw, and the car draws up to that amount (less if its battery is near full) independent of voltage. Hence a common "7 kW charge point" is really a 32 A charge point which ranges from 6.9 kW to 8.1 kW over the allowable voltage range. A “22 kW charge point" presents identical signals to the car allowing it to draw 32 A, but provides all three phases.

Where the cable from charge point to car is provided by the user, the a resistor in the cable also encodes a current rating for the cable, and the car treats that as an upper limit irrespective of what the charge point signals.

Fast DC chargers move the power electronics to the roadside and take commands from the car as to what its battery wants, but they still measure their input current to keep within the programmed supply limits.

Indeed.  Fifty years ago the pump/generators at Dinorwic were reversed according to grid frequency.

My understanding is the Zappi charger provides option to charge solely from excess PV generation (ECO+) as well as a mixture or grid only. Can also be used in a timer mode (TOU) to utilise low cost tarrif like Octopus Go. 

Cheers Andy

ps No I do not have an EV or commercial interest. Obviously there are companies considering the need to integrate charging infrastructure to home renewables.

I have an EV and a Zappi. The Zappi can work in different modes, eco, boost, scheduled. In the Eco modes, it will only charge the car when there is excess power from solar panels, and will stop charging if other appliances start to draw power. The eco modes can be set to allow some mains current to top up the solar panel current to a minimum value.

Boost mode allows for a full 7kW charge on demand. Scheduling enables the charging time to be set to correspond with off peak tariff times. I find that this is used more in the winter when there is less input for the solar panels and when we need a full charge before a long trip.

The Zappi installation consists of 3 elements, a hub which feeds back data to the Myenegi app and web site and enables downloads of software and firmware upgrades. There is a Harvi which connects to CTs in the consumer unit to monitor grid current in/out, solar panel current in. This information is fed to the hub. The app provides a lot of useful information about power distribution to the car, the house, in/out the grid, solar panels.  There is also another unit which can be added if you have a storage battery installed.

I am currently on the Octopus Go Tariff which provides 4 hours per night cheap rate, 5p per unit.  I am closely monitoring the energy consumption distribution to understand the true cost of charging the car.

I have no connection with MyEnergi or any installers.

It is clever innit?

All we need now is a system that can dig our road up to renew the infrastructure and build some new power stations at the same time

Given how much we have to pay in standing charges every year, it's about time they spent some of it upgrading the infrastructure.

Infrastructure is a funny thing.

The roads are publicly owned. The filling stations are privately owned. The electricity network used to be publicly owned, but is now private.

So yes, perhaps electricity consumers will have to pay for more infrastructure. So why don't drivers of EVs pay for the roads? ?

Don't start me on that Chris! 

My little Bipper van is I think £280 next month……..

See how much a HGV pays………

Regards

BOD