This video covers our July 2021 performance figures for our solar pv,
Tesla Powerwall 2 performance here in the UK along with our Tesla Model 3 and Hyundai
Kona electric usage. Plus other things that have happened during the month of July. So stay tuned.
Hi John here and welcome. I like to give you a bit of an update of a couple of things
that have happened during the month of July before we kick off and get into the figures.
Like most people who have a Kaifa MA120 electric smart meter it has not been sending through
the half hourly readings to the DCC. Ours was dead in the water from the 19th of May onwards
and it's an industry-wide issue apparently that Kaifa have been working on with a
resolution to roll out new firmware to fix the problem. Ours actually kicked in again,
I guess when Octopus stroke Kaifa pushed out a test update as our meter has actually recovered
all of the data from when it stopped. And it then stopped again on the 6th of July. The new firmware
has been tested and it's due to be sent out over the air update nationwide in mid-august. However,
these timeslines might slip due to governance and signing off procedures. So we'll wait and see.
We also had our second quarter FiT payment. It arrived actually arrived on the 1st of
June but I forgot to mention it in our June update. The payment was £762.14
bringing the year to date total for the two quarters to £1,007. And these payments go towards
home improvements for example our new front door. Link to that video up there if you haven't seen
that. Okay not that much happened actually in July so let's crack on with the monthly stats shall we.
I'll bring up a graphic on screen which you can pause the video and review if you want to
if you're not familiar with our setup and configuration. Then also have a look down
in the description there's a list of all our components and our system set up etc. First chart
then this is our solar pv generation numbers. For July 2021 our south south west facing 6.34kW
arrays produced a total of 820kWh for the 2 separate rays. We had an average daily solar
generation of 26.5 for the month and very pleased to beat May and June's total. Which is unusual to
do actually because normally it's the other way around, July starts to tail off as we get into the
shorter days. Yeah that's my generation totals. As always I asked you to drop your generation totals
and size of your system in the comments down below and your location. If you fancy doing that it does
provide a really great comparison for other people who read all the comments and provides and proves
very popular with people. And as I've always said I like to see it and comment on it too. So
thank you for those that take the time to do that it's very much appreciated. If we look at our
both arrays individually our 4kW array produced 513kWh. I'll assume kilowatt hours from now on,
I'm not going to say it each time because it gets a bit tedious. And our newer 2.34kW array
produced 307kWh. In terms of the Powerwall and solar working together for our self-power
let's have a look at that. And we faired fairly well actually for self-power during the month.
I did find that I was swapping again between Cost Saving mode and self-power mode
if the weather looked a bit iffy or unsettled, or the forecast wasn't great. I would move to Cost
Saving mode to pull from the grid as needed to get us through the 4pm to 7pm peak period
on battery power and sometimes on sun depending on how sunny it was
and with the high price of the Agile tariff you know it's a thing that
you have to do. If the weather is okay or you know better then we'll be in self-powered mode.
It was only 6 days during the month where we were in Cost Saving mode during part of the
day generally and the remainder of the month we were in self-powered mode and this is much
better than how we fared in June when we were in Cost Saving mode for 10 days during the month.
The Octopus Agile rates have been really high for a few months now
and more and more of the 30 minute time slots are having high rates. And the downside is if
you have to pull from the grid because there's insufficiency solar then the price is higher and
obviously which adds to your electricity bill. As we head towards autumn/winter I'll be keeping
my eye on the rates and the amount that we're starting to pull from the grid and it may even
mean moving away from the Agile tariff and moving on to the Go tariff. That said
we are going to be hit by rising gas and electricity prices over the coming year
as we head into winter. That's been in the news and this is really due to a large ramp up in the
wholesale prices of gas. We were self-powered from the Powerwall and solar contributions for 92% of
the time. As you can see in the stack chart 59% of that came from solar generation and 33% came from
the Powerwall contribution. This chart compares the months of July from 2012 through to 2021.
Values from 2020 onwards are for both arrays whereas before they are just for
the single 4kW array. Our original array produced 513kWh for the month
which means like for like performance is in the middle of the pack if we look back at the previous
months in for July. However, as you can see there the combined arrays did outperform our 2020 total.
The Powerwall in an out chart. The Powerwall certainly seem to be maintaining its 88%
round-trip efficiency. It's 4 months in a row it's been sitting at that figure.
As you can see we stored 299kWh and it was able to supply 264kWh. The additional sunshine really
helped there it meant it worked harder to store more solar and supply more to the house and hence
the 92% self-powered. This chart gives you a little more detail on what happened day by day.
Solar generation, shown in yellow, is strong throughout the month really. The peak
generation was on the 17th of July at 40.8kWh we had 11 days where we generated above 30kWh
in a single day. Our lowest recorded solar day was on the 25th of July at 6.6kWh. House
usage is shown in blue this covers car charging, electric glass kilns, and all other house items
and if you look at the solar generation on 17 days during the month it outstripped house usage
which is good to see. Oh yeah grid pull. Grid pull is shown in red the spikes you will see is where
we ran the glass kilns overnight in the early hours. This was done because the forecast for
the following day was poor solar production which meant we'd be unable to run the glass kiln during
the day purely from solar generation and battery power. We ran the kiln 17 times over the course of
the month and considering that there were just 7 peaks of grid pull it meant that 10 kiln firnings
were done on 100% solar power / battery/. And that works out about 70kWh that would save that
which is good news. We didn't export too much back to the grid as shown in orange. A large
single export was 12 kilowatt hours on the 5th of July this was a day I paid a visit to Nigel
(EVpuzzle) and obviously I had the car and then Jilly, my wife, was out in the Kona so there was
nothing at home to soak up the excess power. If you look at the totals quickly. These charts just
show the totals for the 4 data sources that we've just looked at in the day by day. The house usage
in blue is it perhaps the key one to have a look at at 838.5kWh versus our solar total of 820kWh.
Interestingly enough if I compare the solar generation totals to what the Tesla app is
showing for the month is quite a variance. I take solar totals from the generation meters.
My sort of daily ritual is to record the end of day solar total for both arrays and
then drop them into my spreadsheet, and that's strictly from the generation meters and that's
something I've always done. That means that the spreadsheet solar total I know is accurate.
All of the other totals are taken from the Tesla app; grid pull, grid export, and home usage.
Export was 67.5kWh over the course of the month with import being 74.2kWh.
This is our average daily house usage and our average daily grid usage over the months.
Our average daily house usage was 27kWh that's the blue line. And our average daily pull from
the grid was down at 2.4kWh from 4.8kWh in June that's the red line. So that's all positive stuff.
In terms of what we sent to the grid. We sent 68kWh of excess solar generation back to the grid
in July apart from the 12 on the 5th July that I've already talked about. The remainder was sort
of 1 or 2 kilowatts each day which we couldn't use. A typical scenario is that the battery is
fully charged. The hot water is fully heated up. And one of the cars was charging and this would
typically be the Tesla. Towards the end of the solar day once the charger dropped below 1.4kWh
the zappi would stop charging the car and we would then export for an hour or so until the sun went
down. And that's where those little chunks of 1 - 2 kilowatts would tot up over the course
of the month. This chart shows what we pulled from the grid each month. July we pulled 75kWh
which is half of what we pulled in June which is good to see. And I've always mentioned the
whys and where fours on that total so I won't go through that again. Onto the myenergy eddi which
heats up hot water from surplus solar. The eddi diverted 43kWh of solar generation to heat our
hot water for the month. 251kWh for the year and a running total of 718kWh. I have actually been able
to work out the savings for May and June now as although I've not been billed by Octopus Energy
I did extract the reports from the Octopuswatch app now the data from the meter has actually
started to flow through again. And I've used the average cost per kilowatt hour
for the month to calculate the savings. Not 100% accurate but it's it's certainly near enough,
it's better than the question mark which was there for the last two months.
Onto the cars. The Tesla Model 3 covered 1,145 miles during the month bringing its
total mileage to 13, 258 miles. No issues, nothing to report. I mentioned in my June
update video that I will be changing the cabin air filter, check clean and grease the brake callipers
when it reaches 2 years old in September. I'll certainly do a video on that when I do that.
Oh this is from the TeslaFi website. I've got an account there and it's a really great feature it
shows all the places we've been in the Tesla. And the darker the blue line the more times you've
actually driven that route. And you can also get a lifetime summary as well. Unfortunately
I didn't get the TeslaFi account right away it was about 3 months after I picked up the car
and so it's not quite accurate so there's a bit of disparity there in the total mileage shown
the total miles there. The 273 watt hours per mile works out at 3.7 kilowatts per mile in old money
for those that are interested. In the Tesla we did 7 supercharging sessions where we added a total
of 245.13kWh for no cost. And that's again I will say this but it's worth reiterating it's thanks to
those kind individuals who used our Tesla referral code when ordering their cars. They get 1,000 free
supercharging miles as do we. Thank you to those of you who have used it. Hopefully some more of
you will use it when you place your order for your Tesla. Home charging on the Tesla added 95.92kWh
and then 72% of our total charge for the month came from sunshine with just 38.31kWh
coming from the grid. The Tesla had 3 over-the-air software updates during the
month. I'm not going to go into the details of what each update contained because there's plenty
of videos on YouTube that cover those updates. We're now currently on version 2021.12.25.7.
That's the Tesla. The Kona covered a poultry 354 miles in the month and now has a total mileage of
12,436 miles. It's booked in for its 2 year service or
20,000 miles whichever comes first. It's had no software updates. We did no public charging
and there's no issues or problems to report on it. We are actually still waiting to hear
when we'll get the battery pack swapped. We've taken actually to parking it down the driveway
from the house and away from the Tesla just in case it decides to spontaneously combust! I'm
sure it won't and there's a small minority of them that have but better safe than sorry as
they say. And we actually don't charge it unless it really needs it and we keep that charge level
between 20% and below 20%. Or above 20% and below 80% in the safe zone. So there you go.
That's it. Any questions then dive down into the comments and I'll pick them up from there.
Usual practice of liking, comment, sharing, subscribing if you haven't already it's free and
as ever those actions help get this video shown to more people on YouTube which in turn helps
my channel grow. Thank you for watching and I'll see you on the next video. Alright take care bye.