You know that if you can organise your charging to be between 23:30 and 05:30, then the cost drops to 7.5p/KwH? - a quarter of your day time rate.

I also time delay the dishwasher to run during the off-peak, as well as the washing machine (if I can organise the right load: I don’t do tricky stuff like all-towels or sheets overnight, as these can unbalance the machine and I want to be around when it’s running). I’m also looking at switching back to the immersion heater, at least for the morning hot water.

My last off-peak night-time Intelligent Octopus charge via my Ohme Home Pro added 167 miles / 80% / 41.4 kWh to my e-208 and cost £3.11

Apologies if you already know this, but you should aim to charge only up to 80% or so unless you really need the greater range the next day.

Take a look at some of the other threads if you want some guidance on how to make sure that between them, your car, the charge point, IO and corresponding apps are woking in harmony rather than tripping-up over each other, in terms of settings.

 

So what do you make of my daytime figures? Also i have the onboard 6.6kw charger but is that only for Supermarket/ Service Station chargers?

 

Many people think that your wall box at home is a charger. It isn't. It's just a fancy 'switch' that talks to the car to check safety before engaging the current. The real charger is the 6.6 kW car's on-board unit that then takes that AC mains and converts it to DC and on to the traction battery.

Similarly, the street/supermarket/destination AC chargers are not 'chargers' either. Just switches. The same cable used at home or away just enables power to go from that AC mains supply into the car's charger and become converted to DC to fill the battery.

DC charging from a public Rapid charger uses the other larger socket at the front called a Chademo system and supplies higher powered DC current directly. They always have their own tethered cable.

To calculate the cost is easy. It's simply the number of kW's taken from the supply into the car multiplied by the cost per kW that your power supply tariff states. Your 30 kWh car, if empty at the start and plugged into a 32 amp supply will be filled in 4.5 hours. ( 30kW divided by 6.6kW = 4.5 hours ) And that would cost you 30 kW x whatever your tariff is at that time. ( eg 30 kW x 30p per unit = £9. ) And pro-rata of course depending on how many kWh's you send from the mains to the car per session.

 

You don't have to do anything to enable 6.6 kW charging. The car charges at the best speed it's allowed to, limited by whichever of these is the smallest:

• The capability of the battery itself to take any more charge
• The 6.6 kW capacity of your on-board charger
• The current capacity of the connecting cable (usually 32 A, about 7 kW)
• The maximum charge current announced by the (Ohme or any other) charge point, which could be anything from 6 A upwards.

Whatever cable and charge point you connect, it "just" does the best it can.

 

Best reply yet Thanks Mark

 

My daytime rate is 31.21p/kWh to 37.69p/kWh, depending on the day.
The 23:30-05:30 rate is consistently 7.5p/kWh.

Your Ohme App should show you the day and night rates for you under ‘My Energy’ and the last charge profile under ‘Dashboard’. In ‘Charge Stats’ select ‘VIEW CHARGE SESSIONS’ at the bottom to get a list. Presumably, ‘Manage My EV’ shows your specific vehicle model, which it then uses to calculate charge and mileage stats.

 

If you're on intelligent octopus you should be charging during the off peak times (not now)? Otherwise you aren't getting any benefit?

Check your charger app and ensure its set to only use your cheap period...

 

Given than agile is negative today, it seems quite likely that IO would schedule daytime charging.

 

Excellent replies guys thankyou
I've set the App to charge tonight and deleted any daytime settings so if i just plug it in now 5pm it wont kick in until then?

 

Because the Ohme doesn’t have the Peugeot API implemented yet, I have to take a slightly indirect approach to night-time, off-peak charging:

If I just want it to charge as much as possible - In the Ohme App, I set the maximum I want to pay per kWh as 7.5p and so when I plug it in, nothing happens until 23:30 and then it’ll turn on and then off at 05:30 (or if the car is fully charged first).

If I only want it to charge to 80% - Since I can‘t dictate that the charging should stop at 80% (because the Ohme doesn’t have the Peugeot API) I have to set a charging ‘schedule’ in the app that adds x% to whatever the current charge level is e.g. I have an ‘Add 60%’ Schedule for when the car is at 20% or so, which I swipe on. It’ll then wait until it enters the 7.5p period and adds 60% charge, or stops if it’s after 05:30.

Obviously, the latter is a somewhat cumbersome approach and needs me to not only check the initial charge level, but setup a Schedule for all the common additions I may want to make. In practice, +60% and +70% are all I really need.

Just as a fallback, I also use the MyPeugeot app to set the car‘s system to defer charging until 23:30.

If your Leaf does have its API implemented in the Ohme, then the process should be a bit easier.Another Leaf owner may be able to help you if that’s the case.

 

Please be aware that home charging results in energy loss, this is caused by heat in the cables and the conversion of AC to DC current, by the vehicles inverter, this is in the order of a minimum of 10%.

A 32A charger (EVSE) will draw 6.6Kw through the meter and this results, after loss, of 6Kw actually going into the battery as stored energy.

So a 30Kwh battery will take 5 hours charging to be fully charged (30Kwh / 6Kw = 5 hours) and will cost 33Kw's.
(5 hours x 6.6Kw = 33Kw's)

If using a granny charger the loss goes up to 20%.

Additionally the last couple of % to get to 100% can take an extra hour as this is when the BMS balances all the cells but you only have to do this once a month or so.

 

Please be aware that home charging results in energy loss, this is caused by heat in the cables and the conversion of AC to DC current, by the vehicles inverter, this is in the order of a minimum of 10%.

A 32A charger (EVSE) will draw 6.6Kw through the meter and this results, after loss, of 6Kw actually going into the battery as stored energy.

So a 30Kwh battery will take 5 hours charging to be fully charged (30Kwh / 6Kw = 5 hours) and will cost 33Kw's.
(5 hours x 6.6Kw = 33Kw's)

If using a granny charger the loss goes up to 20%.

Additionally the last couple of % to get to 100% can take an extra hour as this is when the BMS balances all the cells but you only have to do this once a month or so.

Last night my charging was recorded as averaging 7.1 kW (smart meter reported) per hour at 30 amps, albeit it is supposed to be at 32 amps. Why do you say 6.6? I've regularly read others on here getting 7 +.

 

Great reply thankyou