Tesla Powerwall 2 & Solar PV stats September 2021 UK

This is our September 2021 performance figures for 
our solar pv and Tesla Powerwall 2 here in the UK.   Along with our Tesla Model 
3 the Hyundai Kona electric   usage. Plus other things that 
have happened during the month. Hi John here and welcome. September was a 
month of two halves for us mainly because the   second half of it we were on holiday in the 
Norfolk Broads on a cabin cruiser we hired.   You'll certainly see the impact of not being 
at home on our stats when we get to them.   I'm actually considering going away more 
often as it dramatically cuts the home   energy usage. On Friday the 1st of October 
which not strictly September but close enough.   I picked up my stricken iMac from the Apple 
store in Milton Keynes. After much testing   and diagnostic checks they determined the 
issue was caused by a faulty memory stick.   I always install third-party ram in my macs as 
Apple's memory is eye-wateringly expensive. For   example 64BG of 2666MHz DDR4 memory is a £1,000 
from the Apple store, which is actually slow   memory in terms of ram speed. And the same 
ram from a reputable third-party supplier like   Kingston Memory for example is around half the 

Hence I go with third party. But yeah   that was a problem I've never had a memory stick 
fail, and that was the problem. So I've only got   3 sticks in there as opposed to 4. But apart from 
that it's all honky doory and no charge at all. So   thank you very much the Apple store top work! Our 
Kafia MA120 electric smart meter had its firmware   updated pushed over the air sometime in late 
September. And the fix was successful as our   half hourly figures are now filtering through to 
Octopus energy and historical data from way back   to July has started to port over from the smart 
meter. I'm now waiting for a bills to arrive, to   be generated to cover the months from 
July through to September inclusive.   I also ordered a replacement 8m charging cable 
cable from myenergi for our zappi version 1.   The current cable has a break in the wire along 
its length and it gives an intermittent fault.   Sometimes the charging works fine, other times 
even though the car is plugged in you get   the 'ev disconnected' message 
on the screen of the zappi.   I worked out where the break was through sort of 
trial and error of flexing and wiggling the cable.   But decided a new cable was probably the safest 
option rather than shortening the current cable   to remove the damaged section.

The longer cable is 
useful as well as it means I don't have to do the   charging shuffle with the cars to ensure I can get 
them all plugged in. The longer cable reaches both   cars when they're parked where they are side by 
side. I'm guessing going forwards I have to ensure   that I don't wrap the cable so tightly around the 
zappi and make it larger loops to stop it from   flexing so much when I put the car the charging 
cable away. An update on the Kona electric too.   In my September stats video I told you 
about the experience during the service that   I had and there was also a recall update 
that they installed at the same time, but   they couldn't tell me anything about it.

There's a 
link up here if you want to know more about that,   go and check that out. On the back of that 
experience I told you that I wrote and emailed   Hyundai on the 17th August and in the letter I 
requested they initiate a buyback for our car.   No response to date from that letter. 
I'm going to write another letter to   follow up that previous letter and 
send that off to them. However,   I did get a response to my email of the 17th 
August and they responded on the 28th September.   No apology for the length of time to respond. 
41 days to respond to a simple question of   "Can you please advise me when step two of 
the battery replacement will take place?"   The answer they've given in the email, 
I'll bring it up so you can have a look,   is actually incorrect because they state to 
book it in with your local dealer.

But they   also didn't actually answer my question which 
was what I was actually after in the first place!   But I said it was incorrect, so why do I say it 
was incorrect the information that they gave me.   Well at the same time I had a letter around the 
end of September from Hyundai it was actually   dated the 27th September and within under 
the heading 'What action should you take'   it says in black and white there's no need 
to make any bookings with your local dealer   Hyundai Motor UK will make contact with you 
and set up the booking when the vehicle BSA   becomes available, this is the battery pack. 
Which is what I was previously led to believe.   They also state in the letter that the battery 
will be changed anywhere between October   2021 and October 2022, citing battery 
worldwide battery shortages as a reason.   So it could be actually 12 months before our car 
is put right. Until then don't charge over 90%.   Don't park in your garage. Park it away from your 
house and property.

Oh and there's £30 credit for   your inconvenience which I can't claim as I don't 
use their crappy app to charge our car with.   As you can probably tell I'm 
not best pleased with Hyundai. Do not buy Hyundai would be my advice. Cars 
might be great but their customer service   and support stinks. They have no empathy and 
no ethos about putting their customers first.   Okay brighter news. Let's move on to our 
September stats. As ever I'll bring up the   graphic on screen which you can have a pause on 
the video if you want to review it in more detail.   Alternatively have a look down 
in the description down below   there's a complete list of all our components 
and the specifications of those components.

Let's move to look at the solar pv generation 
numbers. For September 2021 with our south   south west facing 6.34kW array we produced 
a total of 627kWh on the 2 arrays combined.   That's just 7kWh more than in August. And 
I've found that looking back historically   that September and August can often be 
very similar in total generation figures.   Our average daily solar generation was 20.9kWh 
for the month. And if we do these sums of our   total generation figure for the period divided by 
the size of our solar array so that's 627 divided   by 6.4kW worth of panels it comes out at 98kWh/p 
per panel. As ever please drop your generation   totals and your kwp performance in the comments 
down below please. As you all know it provides a   great comparison others. Loads of other people 
read and comment on it and obviously I like to   see them as well.

So thank you in advance for 
that. If we look at the both arrays our 4kW array   produced 394 and our newer 2.34 array produced 
233. And you'll see it's very similar to August. Moving on, we'll have a look at the overall self 
power chart. That's how we fared during the month   for self-powered. As we were actually away for the 
last two weeks in September I moved the Powerwall   back into self-powered mode so it didn't pull 
from the grid in the early hours of the morning.   And we were self-powered from the 
Powerwall and solar contributions for 78%   of the month.

As you can see in the 
stack chart 49% came from solar and 29%   from the Powerwall. If you look at the 40% 
solar contribution in August you might be   forgiven and thinking that we had much 
more solar in September to reach the 49%.   And I guess that can be the downside of 
looking at data and charts in isolation.   As you know if you recall we produced only 7kWh 
more in the month from September to August which   certainly wouldn't equate to nearly 
10% more self-powered from solar.   So you have to consider other factors that 
impact solar contributions to self-power,   things like the amount of electricity the house 
used and at what point in the day it was used.   Was the power used during the solar generation day 
or was it used once the solar day had finished.   That gives you a much more rounded picture.

This chart is our year on year the 
chart compares the months of September   from 2011 through to 2021. It's 11 years 
worth of data. Values for 2020 onwards are   for both arrays whereas before then they were 
just the single 4kW array. The 627kWh is the   just a bit behind last year's total 
of 697kWh. Yeah August year on year   really told a similar story as well as September 
so much better then than just gone through. Powerwall in and out char. I did say last 
month I'd be waving goodbye to this chart   as it's going to withdraw it and the reason 
for that was the update the Tesla app meant   the data wasn't easily viewable anymore to 
me to find out the 'To the Powerwall' stats.   In last month's video under the comments Salokin 
stepped in and explained how to get that data.

So   thank you very much for that. I'll bring up his 
comment now. I've since redesigned my spreadsheet   to calculate that to the Powerwall data as 
it's now needed to do some simple maths and   sort of to work out that data from the figures 
supplied in the app. A little bit tedious but can   be done. So well done Tesla for breaking something 
that was okay with their new software update.   I've been moaning a lot in this video, so sorry 
about that. So there's our percentage 84%. I'll   keep my eye on that because that seems a bit 
low to me but I've double checked the figures   so as far as I'm concerned it's correct. 
But yeah we'll keep keep their eye on that.   Day by day chart this gives you more detail of 
what happened during day by day in September.   Guess which day we left to go on holiday? And a 
hint is I charged the car in the early hours off   peak before we left on that day.

The house 
use is shown in blue. On the 17th September   the day of our holiday started basically that's 
when we went for the remainder of the month. The   house usage was either charging the car via solar. 
I left the Tesla plugged in, or we were heating   the hot water via the Eddi on the solar. So lots 
at the beginning and then for a little at the end.   There's also towards the end lots of orange spikes 
as the excess solar went back to the grid. We had   so 2 days of high grid pull shown in red. That was 
the 2nd and the 17th September and both those days   we've charged the cars and added together that 
equated to 92kWh. If we scroll down have a look at   the 4 totals from the day by day. House usage gets 
shown in blue is 743.7 versus our solar of 627.   We'll come to the other two in a bit as we'll 
have a look at them in these charts coming up.   This is our average daily house usage and our 
average daily grid pull usage over the months.   Not surprisingly our average daily house usage 
was up at 31.1 mainly because of the amount   of car charging we were doing.

That's represented 
by the blue line. Our daily average pull from the   grid was down at 9.5 which is the red line. Look 
at what we sent back to the grid. We sent 156kWh   of excess solar generation back to the grid 
and the motto here is never go on holiday!   This chart shows what we pulled from the grid 
and we consumed 285kWh. Moving on to the eddi.   Thankfully I was able to grab the month end 
when we got back from holiday.

First thing I   did when we got in through the door on the 30th! 
The eddi heats our hot water from surplus solar.   This month it diverted 37kWh of solar 
generation to heat the hot water.   For the year 326 and overall running total of 
794. And then on to the cars with the zappi.   The Tesla Model 3 covered 456 miles during the 
month bringing its total mileage to 14,612.   No issues or problems with the car. 
We did 1 supercharging session and 1   public charging session where we added 
a total of 38.46kWh all for no cost.   We used the supercharger in King's Lynn for the 
first time as well.

So that's another one ticked   off the list of superchargers we've been to. 
It's a bit like bird spotting isn't it, do a   a chart of all the superchargers and 
tick them off if you've been to them!   Oh by the way Tesla announced it globally ceased 
its referral program as of the 18th oSeptember   2021 until further notice. There's now no free 
supercharging miles when you purchase a new Tesla   using a referral code. Only solar installations 
have a referral code. So that's a little bit   disappointing but I guess in some respects 
it probably also tells you the success that   Tesla are having in terms of sales. Home 
charging on the Tesla added 137.75kWh.   And 38% of our total charge for the 
month came from sunshine with 149.97kWh   from the grid. This would have been at the 
5.5p/kWh rate on the Octopus Go Faster tariff.   So for August and September, when we moved 
to that tariff, I've updated the costs in   the relevant cells on the spreadsheet to reflect 
that for both cars which you can see there.

The   Tesla had 4 over-the-air updates during the month 
and again I'm not going to go into the detail of   what those are because there's plenty of youtube 
videos covering those. Suffice to say it wasn't   the American release of the full self-driving 
beta but hey-ho! We're now on 2021.32.21. And that was downloaded and installed on the 
24th September while I was on the boat. Actually   I did it remotely so that's all good stuff! 
The Kona covered 417 miles in the month and   now has a total mileage of 13,014.

We actually 
took the Kona rather than the Tesla on holiday   as it's I guess more conventional to operate. 
Perhaps it's only saving grace! I didn't really   want to go through the rigmarole of explaining how 
to use the Tesla key card, how to start the car,   put it in gear, how to lock the car. And then 
set speed limit and valet mode via the app.   Plus I would have received notifications on 
my phone every time they move the car about.   Where we hired the boat from in Norfolk in Wroxham 
we chose undercover parking which means you leave   the keys with them as they often have to shuffle 
the cars around as people return their boats or   arrive to collect their boats.

The reason for 
choosing undercover parking was I didn't want   any well aimed seagull droppings sitting on 
the car's paintwork for 2 weeks because it will   basically scorch the clear coat leaving a blemish 
which is almost impossible to get rid of even with   a da rotary polisher. At least under cover it only 
got dusty. So that's it! Any questions then dive   down into the comments below and I'll pick those 
up as always. Please comment, like, share and   all of those actions help get this video shown 
to more people on YouTube which again helps my   channel grow. Thank you for watching and I'll 
see you on the next video. Alright take care bye..

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