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Charging at home with Solar Panels

AlanIOW

Novice Member
Joined
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Location
Ventnor
Driving
MG4 SE SR
I have a White Trophy on order and went for a test drive yesterday, very impressed, can't wait for the car to arrive. After the test drive, the dealer rep and myself were looking through the numerous pages on the infotainment screen and on the Charging Screen where you can set the maximum charge %, there was also the option of setting the Max Charging Rate, with options of 6A, 8A or 16A [Not sure about 8A and 16A figures]. Does this mean I can use my normal 7Kw home charger and limit the charge rate to 6A? [approx 1320w] This would be really useful as we have a Solar PV system which quite often during winter sunny days maxes out at about 1500w. Currently [Ah Ha!!] we mostly charge our Renault Zoe with a 10A Granny charger on sunny days rather than the wall 7Kw charger as it limits the charge to 2200w and that works fine, we very rarely import much leccy to power the car except in mid winter. Its slow to charge, but that's not a problem and a lot cheaper than installing a Zappi Charger with it's solar options.

If I read the info screen on the test drive car [SE LR] correctly, the 6A and 8A setting will allow me to use the 7Kw wall charger limited to approx 1320w or 1760w without having to use the Granny Charger, has anyone actually tried this or can confirm it will work??
 
It does exactly what you suggest, effectively like the variable option on some granny and charge points. So much more flexible than on most conventional granny charger or charge points, but less so than Eco+ on the better charge points that will put all surplus production into the car.
 
First post to applaud this bit of detective work. Well done!

Grey Trophy on order here. We have a 4.5 kw East/West PV array and I'm diving (for the first time) into the world of Chargers.

Currently best option looks like a Zappi/Ohme etc, but being able to lock the charge rate on the car will be effective in the interim. Nice find!
 
First post to applaud this bit of detective work. Well done!

Grey Trophy on order here. We have a 4.5 kw East/West PV array and I'm diving (for the first time) into the world of Chargers.

Currently best option looks like a Zappi/Ohme etc, but being able to lock the charge rate on the car will be effective in the interim. Nice find!
The wallbox charger is worth checking out as well - Eco-Smart Solar EV Charging
 
The wallbox charger is worth checking out as well - Eco-Smart Solar EV Charging
That's the charge point I have. (Not that I've ever had anything to plug it into yet*). The app allows you to adjust the charge current between 6A and 32A.

* I got it when I was supposed to be getting a Volvo V60 PHEV as a new company car (before Volvo decided to cancel the order almost 8 months after it was placed). The upside was that Volvo gave me a £500 contribution (in lieu of them supplying a charge point, which was the offer available at the time), I got a £350 OZEV grant, plus a £250 Energy Trust Scotland grant. The installed cost of the Wallbox Pulsar Plus was £940, so I ended up with a free charge point plus £160 rebate. 😎
 
I have a White Trophy on order and went for a test drive yesterday, very impressed, can't wait for the car to arrive. After the test drive, the dealer rep and myself were looking through the numerous pages on the infotainment screen and on the Charging Screen where you can set the maximum charge %, there was also the option of setting the Max Charging Rate, with options of 6A, 8A or 16A [Not sure about 8A and 16A figures]. Does this mean I can use my normal 7Kw home charger and limit the charge rate to 6A? [approx 1320w] This would be really useful as we have a Solar PV system which quite often during winter sunny days maxes out at about 1500w. Currently [Ah Ha!!] we mostly charge our Renault Zoe with a 10A Granny charger on sunny days rather than the wall 7Kw charger as it limits the charge to 2200w and that works fine, we very rarely import much leccy to power the car except in mid winter. Its slow to charge, but that's not a problem and a lot cheaper than installing a Zappi Charger with it's solar options.

If I read the info screen on the test drive car [SE LR] correctly, the 6A and 8A setting will allow me to use the 7Kw wall charger limited to approx 1320w or 1760w without having to use the Granny Charger, has anyone actually tried this or can confirm it will work??
I have a 6a granny charger which then is 1400 watts approx...coupled to my solar panels, so charging the car never costs anything - coupled with a little script on a raspberry pi which asks my solar setup how much i'm producing, and then turns a shelly smart plug on or off, if i'm producing at least 1600w (to give 200w to the house). It works really well, for me at least
 
I have a 6a granny charger which then is 1400 watts approx...coupled to my solar panels, so charging the car never costs anything - coupled with a little script on a raspberry pi which asks my solar setup how much i'm producing, and then turns a shelly smart plug on or off, if i'm producing at least 1600w (to give 200w to the house). It works really well, for me at least.

That's a fascinating low-cost solution. I've got some tech know how (but not a programmer, more on the hardware side)

Tell us more about this "little script"....
 
That's a fascinating low-cost solution. I've got some tech know how (but not a programmer, more on the hardware side)

Tell us more about this "little script"....
the solar power monitoring thingy is a webpage, so i download that webpage as a text file:

wget -q http://192.168.1.26 -O $zepath/index.html

(ignore the $zepath)

Then I look for the line I want ("Last System Power") and extract the value:

val=grep -A 1 "Last System Power" $zepath/index.html | tail -1 | cut -f 2 -d '>' | cut -f 1 -d ' '

Once I have that number in $val I can do whatever I want with it, in my case turn a shelly (Home - Shelly Cloud) Plug on or off:

if [ $val -gt $carcons ]
then
echo -n " : (> $carname $carcons)" >> $logfile
if [ $ison -eq 0 ]
then

cmd="$zepath/shelly/turn"$car"on.sh"
$cmd
cmd="$zepath/shelly/is"$car"on.sh"
ison=$cmd
if [ $ison -eq 1 ]
then
echo -n " : $carname>on" >> $logfile
fi
fi
fi

Obviously the whole script is a bit more complicated than that, mainly because it handles my hot water boiler too, and keeps stats, and generates a monitoring webpage, and so on, but the guts of it are there.

This is in bash, the basic scripting language of linux, and available by default on the rpi.

The shelly turn on/off and status commands do the same thing really. The shelly interface is just a webpage and you can do things like http://shelly/meter/0 (which returns a lot of stuff, but the first number is the current wattage being provided by the plug), and http://shelly/relay/0 (which will tell you if it is on or off), and then http://shelly/relay/0?turn=on (which unsurprisingly tells the plug to turn itself on).

I really like the setup, it cost basically nothing (well, I had to buy a granny charger capable of doing 6 amps :), a rpi, and a shelly plug - so around 200€ (i'm in France)). The coding took the best part of a weekend I suppose. I put my solar panels in in march/april - and since then I have spent nothing to charge the car, except once when I went on a long trip and needed it to be at 100%
 
I originally started trying to charge our original MGs using granny charger from solar using our ohme charger but the issue I had was that when the sun goes behind clouds, it either started pulling power from the grid or draining our storage battery (neither ideal), decided just to bite the bullet and switched to a zappi 2, this is much better as it varies the charge with available solar excess in eco++, leaving the battery’s topped up and not pulling from the grid.
I like the solution above but it does seem like a bit of indepth knowledge would be required to pull it off, I looked a using home assistant at one point but even this didn’t seem too straightforward to me.
 
I originally started trying to charge our original MGs using granny charger from solar using our ohme charger but the issue I had was that when the sun goes behind clouds, it either started pulling power from the grid or draining our storage battery (neither ideal), decided just to bite the bullet and switched to a zappi 2, this is much better as it varies the charge with available solar excess in eco++, leaving the battery’s topped up and not pulling from the grid.
I like the solution above but it does seem like a bit of indepth knowledge would be required to pull it off, I looked a using home assistant at one point but even this didn’t seem too straightforward to me.
TBH home assistant looked complicated to me 😂
 
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