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In 2023 we generated 7.47MWh, which exceeded my expectations by some margin. If this is a bad year, then I can't wait for 2024 to be a good one.

Solar generation remained poor this month with just 170.4kWh, an average of 5.5kWh per day. The highest seen has been 20.8kWh. In December 2022 we generated 265kWh, an average of 8.6kWh per day.

Solar generation has been really poor this month with just 85.6kWh in the first 16 days, an average of 5.4kWh per day. The highest seen has been 20.8kWh.

In December 2022, we generated 265kWh, an average of 8.6kWh per day, with a low of 0.2kWh and a high of 21.3kWh. I don't think we will do that well this December!

Today we hit a total of 8MWh (8000kWh) since our installation was completed on 18/10/2022. That's 8000kWh in 409 days, an average of 19.6kWh per day.

November was a properly mixed month for weather, with it turning much cooler as we go into December. The central heating was on a lot of the time. We generated a reasonable 357kWh this month though, an average of 11.9kWh per day.

Our total Return On Investment (ROI) this month was £298.08 (£72.16 electricity + £36.35 exports + £45.27 gas + £144.31 transport) based on my monthly analysis.

There we two days where we had to charge the CUPRA Born during the evening rate (off peak) to ensure it would be at 100% for a trip to London the next day.

Another example of our Tesla Powerwall doing it's thing. The 5kW charge and discharge rate is an important factor. It means it can charge fully in the 3-hour cheap rate Octopus Flux tariff window and also handle loads such as cooking a roast dinner during the peak period.

Our Tesla Powerwall is doing an amazing job of ensuring we only use cheap rate energy, even on the days when solar generation is close to zero. It got down to the 20% reserve level today for the first time. I could set the reserve level even lower but, it is a very rare event vor it to get this low. The dishwasher as used during the day, the washing machine twice and the tumble dryer too.

The big changes for October are the some colder weather and the new Octopus Flux tariff prices. We have started using the gas powered central heating this month. Having crunched the numbers on Octopus Intelligent, I decided to stick with the Flux tariff. I would save a little bit more on Intelligent but, you lose a lot of control. I want to have fixed periods, so I can better quantify our usage and costs through our first winter with the Tesla Powerwall in place.

We generated 509kWh this month (525kWh according to our generation meter). In October our export revenue matched our home electricity costs.

The extra hour in the day on the 29^th has required some updates to my spreadsheet! 🤣

Decided to test out the new fast chargers at the Martlesham Park & Ride today. Spent £8.57.

We have yet to have a single day where we have generated no energy but, today we got pretty close with just 1.1kWh. This was due to storm Babet over the UK. It's not the worst day we've seen though. The lowest was 0.2kWh on 4^th December 2022.

The 18^th October means our solar panels have been installed for exactly one year. In those 365 days we have generated 7481kWh or 7.48MWh. By my calculations we have also saved just over £4,000 in energy and transport costs. It would have been more but, our Tesla Powerwall was not installed until April 2023.

Another step forward today for our MX-5e EV project. We have removed the engine and gearbox and are stripping the car of all its internal combustion engine related parts before we start trial fitting all the EV bits.

From the 1^st October, Octopus Energy are lowering the Octopus Flux tariff rates (both import and export) by 8%.

Ordinarily this would be a bad thing, because we export a lot more than we import but, with winter coming this is now a good thing. Sadly, the standing charge has not changed.

Today we will hit 7MWh (7000kWh) of solar energy generated since our system was installed by Greenscape Energy Ltd 342 days ago. Their predicted annual generation in our first year was 6891kWh and this aligned closely with the 6872kWh predicted by the European Union PVGIS service. We are on target to exceed 7.5MWh in our first year.

A big step forward today for our MX-5e EV project. My son and I have been working on this since March and we now have the Nissan Leaf motor running on our test bench😎

This week has been an amazing week for solar generation, albeit not as high as our best week so far (266.1kWh from 12^th to 18^th June 2023). 246.5kWh in a week is a daily average of 35.2kWh.

This week has been particularly hot, which is why we have not been generating more than 42kWh each day. Solar panel output reduces slightly as the temperature rises. Friday 8^th was hazy (24.3kWh) because of Saharan dust in the atmosphere.

Our solar generation is ensuring that our energy bills are negative through the spring and summer. Our exports are covering our electricity and gas usage, including standing charges and our CUPRA Born usage. We are building up credit to use through the winter months.

August has also been a bit wet and cloudy for the whole of the UK. Our total Return On Investment (ROI) this month was £353.00 (£65.07 electricity + £152.83 exports + £5.45 gas + £129.66 transport) based on my monthly analysis.

July has been a wet and cloudy month for the whole of the UK. Our total Return On Investment (ROI) this month was £305.66 (£70.62 electricity + £149.43 exports + £10.97 gas + £74.64 transport) based on my monthly analysis.

I download my smart meter data from the Octopus Energy website and store it in a spreadsheet. This allows me to calculate energy costs and export earnings to the nearest penny. It also allows me to use my data to see what I would pay/earn on any other tariff. The is currently my best option by some margin and is likely to remain so until we get into November.

Despite the cloudy weather this month and 163% of the average rainfall for Suffolk, we generated a lot more solar energy than I expected. The lifetime generation meter is now at 5514kWh.

Arrived back home from a trip to Poland and my contextual smart home has done a great job of saving us energy by using occupancy and presence. As you can see from this graph, we used zero gas whilst away as it it didn't need to heat water or our home. We are currently on target for a >30% saving on our historical average gas usage this month.

Today was a very good solar day 😎

From the 1^st July 2023, Octopus Energy are reducing both the import and export prices for the Octopus Flux tariff. Gas prices are also falling from 10.204p to 7.399p per unit.

Using my June data as an example, I would have been paid £165.38 instead of £191.94 (£26.56 less) for exported energy and paid £83.49 instead of £92.36 (£8.87 less) for the imported energy used in our home. So overall, I appear to be £17.69 worse off but, this doesn't include the cheaper EV charging that I now get. This would be reduced to £35.48 (was £39.25), saving me another £3.77.

June has been an epic month for solar generation, more than we could have hoped for 1013kWh 🤯 Our total Return On Investment (ROI) this month was £417 based on my monthly analysis.

With a huge storm passing through and lots of thunder and lightning overhead, I took our home off grid for the first time today. Our solar system was also generating zero at the time due to the storm clouds. It's really easy to do this with a Tesla Powerwall and it is simply achieved using a button in the app. It is seamless too, with no interruption in power to any home devices.

The Tesla Powerwall can easily power our home for 18 hours or more and much longer with solar generation too. We could easily run our home off-grid for the sunnier 8 months of the year.

266.1kWh is the best generation we have ever seen in one week, exceeding the previous best of 253.7kWh at the end of May 2023.

The Solcast forecast forecasts for the coming week looks good!

Today we hit 4MWh (4000kWh) of generation 🤯 Our system went live on the 18^th October 2022 and we generated our first 1Mwh on the 29^th April 2023 after 103 days, 2MWh on the 4^th April 2023 after another 65 days, 3MWh on the 10^th May 2023 after another 36 days, 4MWh on the 10^th June 2023 after another 31 days. That's an average of 32.2kWh per day for this last MWh.

June has got off to a pretty good start and today was the first properly sunny day with clear skies. Despite this, we generated 46.0kWh, which is less than our previous best on the 26^th May with 46.4kWh. This is due to a lower daily peak power (5.65kW) and this simply is down to the sun being higher in the sky more of the time and hitting the solar panels at more of an angle. The solar zenith is reaching 30° and this makes our 40° roof less advantageous at this time of the year. At it's highest point the sun is at a 20° angle to our solar panels, effectively reducing their output power.

May has been an amazing month for solar generation, our best month so far. Our total Return On Investment (ROI) this month was £426 based on my monthly analysis.

Today we saw another generation record with 253.7kWh in a week. That's an average of 36k.2Wh per day 🤯 This also means we have already beaten our last months 860kWh generation record.

Another daily solar generation record for us today with our smart home solar installation project. We generated 46.4kWh and also set more records by exporting 41.74kWh, earning us £10.10 for our exports on the Octopus Flux tariff.

The one downside with the Octopus Flux tariff is the 3-hour cheap rate window to charge an EV. We used our CUPRA Born today and need it to be at 100% for a trip to London tomorrow. In 3 hours, we can add (3 × 7.4kW) 22.2kW which equates to about 38%. If the car battery is less than 62%, then I have to charge using solar power or in the evening after the peak rate period. I've only had to do this tonight so far and I charged it at 9pm. It uses power from my Tesla Powerwall and there is no getting around this. Fortunately it has a 13.5kW of usable capacity and having got the car to where it needed to be, the Powerwall was still at 62% 😎

Another record today for our smart home solar installation project. 45.6kWh is the highest daily generation I've seen so far. It would have been a new export earnings record on Octopus Flux tariff too but, I was away this weekend and the CUPRA Born was left plugged in from charging over night, using 4.7kWh of the solar energy generated to get to 80%.

The 'tail' from 6pm is a limitation of my roof orientation. Our roof faces 154° SE, which is 26° to the East of South and is inclined at 50°. This means that the sun stops shining on our roof and panels shortly after 6pm.

After setting a new record on the 16^th for export earnings on the Octopus Flux tariff, we broke it again today. We exported 39.2kWh (of the 43.1kWh generated) and earnt £9.48 🤯 That takes our earnings for this month to £100.41.

Having interfaced my Tesla Powerwall to my contextual smart home using the Tesla API, I can now fully populate my smarthome energy dashboard 😎

Kicked off my project to control my Tesla Powerwall via the Tesla local API.

Trying out some clever smart home software I have written to reduce my gas usage. It seems to be working well! It's linking my smart home solar installation project with my Drayton Wiser smart thermostat.

Today we hit 3MWh (3000kWh) of generation 🤯 Our system went live on the 18^th October 2022 and we generated our first 1Mwh on the 29^th April 2023, in 103 days. We generated 2MWh on the 4^th April 2023, after another 65 days.

Today was also our best day so far for exporting on the Octopus Flux tariff. We generated 36.3kWh and exported 32.4kWh, earning £7.92.

My Tesla Powerwall is doing a brilliant job of maximising my income on the Octopus Flux tariff for the first four days of this month. I'm currently testing it in 'Time-Based Control' operational mode, so I've configured the Tesla app with the Flux rates. This is how it works out of the box, so I'm doing nothing clever and just letting it do its thing.

In these four days we have generated 131.5kWh (an average of 32.9kWh per day). We have imported 25.4kWh costing £6.13 and just 0.4kWh of this at peak rate. We have exported 106.4kWh earning us £26.08. So Octopus Energy owe us £19.95, less standing charges of £1.68. At this rate, Octopus Energy will be crediting us over £140 on our electricity bill this month 😎

Today was my first test of charging the CUPRA Born over night using our Zappi smart EV charger and my Tesla Powerwall in 'time-based control' operational mode. The Zappi put 14.6kWh into the EV, to get it to 80%.

In 'time-based control' operational mode, the Tesla Powerwall handled this perfectly, allowing the Zappi smart EV charger to only use energy from the grid. The Powerwall also charged up in the same cheap rate window for my Octopus Flux tariff. The ripples seen in the peak energy usage are the dishwasher during its cycle.

Kicked off my 'unlimited Basil' supply for this year.

With all the sunshine, it is time to open up our smart garden lounge ready for use again 😎

I set my to 'Time-Based Control' operational mode late last night and straight away you can see the change in behaviour. It charged to 100% during the Octopus Flux tariff 'Flux rate' window (02:00 - 05:00) of 20.39p/kWh, so that it could be used to power the house outside of this period. It then basically powered my home all day, whilst all my solar generation was exported, earning me a minimum of 22.98p/kWh.

So with this change of focus and 30.9kWh generated today, the Tesla Powerwall managed to export 26.6kWh of it. The Octopus Energy data says we earnt £6.39 today. We imported 5.6kWh and none of it at peak rate, costing £1.26.

Wow! We generated 860kWh this month 🤯 Our total Return On Investment (ROI) this month was £325.55 based on my monthly analysis.

The SoC was 49% at sunrise and this is the lowest SoC it has reached so far. The Tesla Powerwall charged rapidly, reaching 65% by 8:30am and 100% at 9:45am. The little 'dip' in the SoC graph was me grilling bacon, making toast, the coffee machine and my wife using the kettle 😊

The CUPRA Born was plugged into the Zappi smart EV charger at 9:45am and unplugged at 2:30pm, putting 18.7kWh into our EV.

One of the best features of the Tesla Powerwall is that it can deliver 5kW continuously and up to 7.5kW for short periods. This is one of the key reasons that we haven't imported ANY energy since I started my testing. It can handle things like the kettle, grill and coffee machine all being on at the same time.

You still have to be "solar aware" though and do most of the load intensive daily tasks when there is solar generation to handle the loads or support the battery.

The SoC was 54% at sunrise and the Tesla Powerwall charged rapidly, reaching 79% by 8:30am, 86% at 9am and 100% at 9:30am.

From 9:30am we charged the CUPRA Born via our Zappi smart EV charger.

At sunset yesterday, the Tesla Powerwall SoC was 100%. The SoC was 63% at sunrise. It dropped down to 60% at 8:15am, then slowly started to charge. The SoC was 63% at 9am and slowly crept up to 71% at noon. The SoC was 85% at 1pm, 89% at 2pm, 92% at 3pm and the highest SoC reached was 97% at 3:45pm.

The Solcast forecasts for the coming days look good! 🌞

At sunset yesterday, the Tesla Powerwall SoC was 100%. The SoC was 53% at sunrise, 61% at 8:30am, 69% at 9am, 88% at 10am and 100% at 10:45am.

Our CUPRA Born is away from home today, so we are exporting until sunset on the Octopus Flux tariff rates.

At sunset yesterday, the Tesla Powerwall SoC was 100%. The SoC at sunrise was 66%. This is a really useful benchmark. We used just ⅓ of its capacity between sunset and sunrise.

The SoC was 67% by 8am, 74% at 8:30am, 80% at 9am. At 9:15am the SoC was at 84% and the washing machine was turned on. We were generating about 2-3kW. The washing machine can use up to 2.8kW. The Dyson vacuum cleaner and several hair dryers were also being used but by 10am the SoC was 91% and it reached 100% at 10:15am. It sits at 100% until sunset.

My In Home Display (IHD) has become a lot less useful since the Tesla Powerwall was installed. Most of the time it looks like this now.

Once the Powerwall SoC reaches 100% we start exporting and this generates a useful income on the Octopus Flux tariff. We exported from 10:15am to sunset, a total of 11.1kWh. The period of low exports from 12 noon to 4pm was me charging the CUPRA Born using our Zappi smart EV charger. I switch off the EV charging at in order to export as much as possible during the peak period at 36.58p/kWh.

The fairly large export 'ripple' whilst using my Zappi smart EV charger is due to the 200W 'export margin'. This will be reduced in the coming days.

In the period from 12 noon to 4pm we put 13.4kWh into our CUPRA Born. So we could have exported 24.5kWh today if we didn't charge the EV.

After a little bit of testing yesterday, I've decided to only run my Tesla Powerwall in 'Self-Powered' operational mode for the rest of this month, whilst I get to grips with the flows of energy. This will allow me to benchmark our system. I've also switched off grid charging as we are generating 29.5kWh per day on average this month, which is more than enough for our needs. For the rest of this month we will only be exporting energy 😎

At midnight, the battery charge state was down to 63% and a lot of that was me testing the Zappi smart EV charger. The lowest it got to was 41% and I ran the dishwasher over night which was not useful 🙄 We also cooked tea using our main 3kW oven. Despite all of this, no energy was imported at all 😎

The Tesla Powerwall state of charge (SoC) was back up to 65% by 8:30am, 75% by 9am, 86% by 9:30am and shortly after 10am it reached 100%. From then on, we were exporting again and making money! 😎

My main focus today is to get the Tesla Powerwall and Zappi smart EV charger to play nicely together. At the moment, the Zappi smart EV charger drains the Tesla Powerwall when charging at night or via solar power during the day. The MyEnergi support forums are incredibly useful and suggest changing some advanced settings on the Zappi smart EV charger.

I resolved the issue with the Zappi smart EV charger charging on solar in Eco+ mode, simply by setting the 'export margin' to 200W. This can be reduced slightly through more testing to see what works best. Our CUPRA Born is now chargeable on 100% solar energy again.

To avoid battery drain, there is an advanced setting under 'Supply Grid' which needs to be changed to 'Avoid Drain'. I will now do some more testing today and tonight.

My first full day with a Tesla Powerwall. We generated 28kWh today, which is about the daily average for April. The Powerwall started at 41%, which is also lower than we would typically see. It should reach 100% by 9:30am at the latest.

Once the battery was charged we had some time to plug in the CUPRA Born and put 6.4kWh into it. My son baked cookies in the early afternoon and a small (2kW) oven was used for dinner tonight. Despite all this, we imported zero and exported 7.2kWh. The Tesla Powerwall is doing a brilliant job of soaking up the transient loads from appliances and actually discharged 4.4kWh to power the dishwasher and cookers.

Greenscape Energy Ltd arrived this morning with my Tesla Powerwall 🙂 It has been a long wait but it has been worth it.

My wall is strengthened by two metal rails running up the wall from the concrete floor. These are bolted to the wall using 10mm × 130mm threaded studs, which are bonded into the wall. My measurements were almost perfect, with one bolt just a few millimetres out. With a bit of fettling, the mounting bracket was attached to the frame in just a few minutes.

Getting the 125kg Tesla Powerwall up in the air and high enough to drop down onto the mounting bracket was a real challenge. It took four of us to get it up on the wall!

I'm really pleased with how it has all turned out. It is a very tidy installation both on the roof and in my garage. I have the room I need to get a car in the garage still too.

The Tesla Powerwall was delivered 20% charged. As soon as it was switched on, it started charging via solar energy and by the end of the day was well above 90%. Despite using things like the washing machine and tumble dryer, no energy at all has been imported since it was connected 😎

For now, I am running my Tesla Powerwall in 'Self-Powered' operational mode and I have also switched off grid charging. I figure we are generating more than enough to need grid support and this will help me better understand how well it works.

You can't really see it in this picture but, the Powerwall has a green line lit up with LEDs.

To prove I can still get a car in the garage, this is our Open-Source Sports EV (OSSEV) project MX-5e tucked up against the wall.

Managed to finish the metal frame and fix it to the garage wall before I head off up to Leicester in the CUPRA Born. Because my garage wall is made from Thermalite blocks, I need to strengthen it before the 125kg Tesla Powerwall can be mounted on it! And it arrives on Monday morning!

It was a fantastic weekend away and my daughter, Emma was crowned Miss Supranational 2023 😎

I have written an article on How To Make The Most From The Octopus Flux Tariff.

We generated 43.3kWh today, which is not the highest we have seen but getting 34.1kWh into our CUPRA Born using our Zappi smart EV charger is a new record. And this was all before 4pm, when we focus on exporting energy to get paid as much as possible on the Octopus Flux tariff.

Charged the CUPRA Born for the first time on the Octopus Flux tariff, through necessity. My daughter took it to Colchester yesterday evening and has to be in London this morning (which needs 100% SoC to get there and back without range anxiety). It required 21kWh to fill the car up and this was only just achievable in the shorter 3-hour cheap rate window that the Octopus Flux tariff provides. At 20.39p/kWh this cost £4.49, compared to the £1.58 we used to pay on Octopus Go tariff (7.5p/kWh).

Fortunately we do over night charges rarely as we are aiming to run our car on 100% solar energy as much as possible, even if it isn't the cheapest way to do it 😊 With the Octopus Flux tariff we actually get paid more to export energy during the day (22.98p/kWh) than the Flux rate costs (20.39p/kWh), so charging the car overnight works out slightly cheaper!

The key to getting the best possible Return On Investment (ROI) with tariffs like Octopus Flux tariff is to keep exporting through the peak rate (16:00 - 19:00) period as much as possible. We do all we can to ensure this happens and make sure we don't use high load appliances in this period.

Today I used my slow cooker to make a chicken in red wine dish. It using about 180W over a long period and is one way to avoid importing energy on less sunny days or at the end of the day. It means we don't use our cooker, which uses 2700W. This is just one of the many ways I save energy.

Proof that April has been a much better month than March. We have generated as much energy in the first half of April as we did in the whole of March. We are averaging about 29kWh per day so far.

I received my first Octopus Energy referral payment today 🙂 If you are considering moving to Octopus, you can use this referral link and Octopus Energy will give us both £50.

I've been super busy with my son, these last four weeks as we build our next EV 😎 As part of our Open-Source Sports EV (OSSEV) project we are currently taking a 1992 Eunos Roadster (Japanese Mazda MX-5) completely apart, in order to do a full restoration and conversion to electric power. You can read about our MX-5e plans and follow our daily progress.

I went back and had another look at the generation curve from the 4^th April (the highest daily generation I've seen so far) and when viewed in landscape mode, I am confident it is showing signs of the Enphase microinverters clipping the power output. The generation curve has an obvious flat top to it and I was expecting this to start happening soon. This means that higher daily generation is going to happen but, it will be down to the days getting longer and the sun getting stronger in for longer in the day. It will be interesting to see just how high it goes.

We are now on the Octopus Flux tariff. The import side of this happened within and hour. The export side took longer to set up. We are now making proper money from our exports 😎 We generated 36kWh today and exported over 28kWh. Most importantly, we are already generating through the peak period of 16:00 to 19:00. Exports in this time window are paid at 36.58p/kWh.

To put this tariff change into perspective, instead of the £1.14 we would have been paid on the Octopus Go tariff, we were paid £6.55 for our exports today.

I moved our tariff today, across to the Octopus Flux tariff. This means reworking my smart energy management, to account for the different time periods and rates used by this tariff. If I get this right, then Octopus will be paying us to use and export energy over the next eight months 😎

Today I saw that we were exporting nearly 5.9kW at times. This has convinced me that now is the time to change our tariff to the Octopus Flux tariff.

This is another first for our smart home solar installation project. At times, our smart meter IHD was showing we were exporting 5.85kW. Our house typically uses 200-300W, so we must have been generating over 6kW. Whilst the IQ7A Enphase microinverters can provide 349W continuous (17 × 349 = 5933W), it has a peak output of 366W (17 × 366W = 6222W) which might explain this. Our MyEnergi app was also reporting a peak power of 6.1kW at the time.

So far this month, we have exported more than we have imported. With out Tesla Powerwall installed, we would not be importing at all this month.

It doesn't seem that long ago that we hit our first megawatt of energy generated. It was in fact on the 29^th January. Today we reached 2MWh 😎

The second MWh was generated in 65 days! The first 1MWh took 103 days.

And the icing on the cake is that today marks three record breaking generation days in a row, with 44.8kWh today. Our CUPRA Born was already at 100% from the last few days, so we exported 33.9kWh. I desperately need our Tesla Powerwall installed now.

My Solcast forecast was for 43.4kWh today and we got very close with 43.0.kWh 🌞 This is another new record for my smart home solar installation project.

The generation graph shows evidence of the odd cloud, so there is still more to come and the sun is still not that strong.

Woke up to some pretty impressive Solcast forecasts this morning 🌞

For the first time since our installation was completed (back in October 2022), we saw 5.9kW peak power generation. In theory, our Enphase microinverters will start to clip the power at around 6.0kW fairly soon.

We actually exceeded the Solcast forecast and generated 38.4kWh, another new daily record. As you can see from the graph, we had a fair bit of cloud in the morning too. Our Zappi smart EV charger managed to put 24kWh into our CUPRA Born, despite it not being connected all day.

Today was a new daily energy generation high at 34.6kWh 🌞 You can see from the generation curve that there is plenty more to come.

There is going to be a bit of a pause in my smart home and solar work, whilst I get our Open-Source Sports Electric Vehicle (OSSEV) project moving. We have bought a 1992 Eunos Roadster to be our test platform and we are restoring it prior to doing the EV conversion. You can follow our progress.

Today was a new generation high for 2023 with 30.4kWh. It wasn't even really that sunny today and peak power was 5.2kW. The difference is the length of time the sun is up in the sky. Solcast predicted 33.8kWh for today but, the cloud drifted in late afternoon quicker than I expected.

I've seen some interesting comments in the solar Facebook groups where people claim they have seen higher peak power output than their panels are rated for. This is clearly a measurement error because the sun is not very strong yet and is still too low in the sky. The Earth's tilt means the sun is still having to pass through a lot of atmosphere to reach us here in the UK.

I have plotted the peak power seen on some of the best generation days since my installation was completed. The highest was today at 5.8kW and my Enphase microinverters will limit the power out of my 6.63kW of panels to 6.0kW. This is called 'clipping' and I haven't seen it occur yet. This data comes from the Enphase Envoy hub as it is closest to the generation and is thus more accurate.

Being away also meant we imported just 26.7kWh over those 8 days or 3.4kWh per day. What looked like a super sunny start to March has turned in to very cold weather and snow 🙁

Going away on holiday allows you to check how much energy your home uses whilst you are away. Whilst we were away the temperatures were near freezing most days. When my contextual smart home knows we are away, it maintains the house temperature at 15°C, so the heating is kicking in every so often and because our heating uses a hot water tank, this is also kept up to temperature. It's not the most efficient way of doing things! Over the first 8 days of March, our home consumed 43kWh or 5.4kWh per day.

Later this year I'm going to install a new hot water tank to enable better solar water heating and to also separate our heating system from our hot water tank.

March got off to a good start, with a family holiday in Dubai from 27^th February to 9^th March. We were away when energy production hit 30.0kWh for the first time this year 😎 The peak power generated is up to 5.6kW. Being away meant we also exported 27.9kWh though 🙁

Although today has been a mixed weather day, when the sun has come out, I've seen 5.6kW being generated. I've not seen output this high since October last year.

A lot more testing with my current transformer interface boards to make them more accurate.

With help from a friend, I have finally realised why my Enphase microinverters appear to use over 300W at night time, as measured using my AC current transformer sensor. In practice they use very little real power at night and this is explained in this video.

Octopus Energy announced their new tariff called Octopus Flux. I'm currently doing my analysis of this on my tariff page. The assumption is that you only import at the cheapest time and store energy in your battery. You can then export at better rates too, especially if you can target export at the peak rate period (16:00-19:00). It looks like the best option for me, assuming I have my Tesla Powerwall installed.

Our best weekly generation since our smart home solar installation project started. We generated 125.4kWh this week, an average of 17.9kWh per day. I honestly thought we would hit 150+kWh but the weekend has been gloomy.

This week I've spent a bit of time trying to work out the best tariff for each month of the year. It very much depends on your personal usage and usage profile. I'm also having to work this out for two scenarios; with and without our Tesla Powerwall.

This week is already our best week ever for solar generation (103.5kWh) and we have three days left to go! 😎

[EDIT] On taking a closer look at the data, we generated 123.5kWh in the week of 16^th Jan to 22^nd Jan. We are going to exceed that this week though.

Having been asked for advice on solar panels and battery storage so many times, I decided to write a guide on on how get started with renewable energy.

So close to my first 30+kWh day of the year but not quite! 😎 The last time I saw more was on the 18^th October 2022, the day after we had our solar panels installed. We generated 32.5kWh on that day. Peak power output today was 5.0kW.

As part of our Open-Source Sports EV (OSSEV) project, I've bought some Arduino 16MHz CAN bus MCP2515 transceiver modules. The plan is to experiment with them and learn more about the CAN bus technology.

The Octopus Energy app now shows our exports 🙂 This 13kWh is worth just 53p to us but it all adds up and once we get into the sunnier months, I will move to an 'agile' export tariff. We will then get paid a LOT more for each kWh exported and my smart home will target the peak periods, exporting as much as possible, to maximise our Return On Investment (ROI).

A good start to the month! 🙂 Octopus Energy have now set up our Smart Export Guarantee (SEG) payments, so we now get paid 4.1p/kW for exported energy. My smart energy management aims to maximise our Return On Investment (ROI) and is based on using what we generate to reduce other, more expensive costs as much as possible.

The January statistics for my smart home solar installation project are impressive!

Hit a milestone this morning 😎 Our first 1 megawatt hour (1000 kWh) of energy generated since our installation went live on 18th October 2022. This was achieved in just 104 days over Autumn & Winter, a daily average of just under 10kWh 🤯

This week ending Sunday 22^nd January 2023 has been epic for solar generation, with 123.5kWh over the seven days 😮 That's a daily average of 17.6kWh in winter! 🤯

Despite all the other things using power in our home (heating, washing machine, tumble dryer, etc.), our Zappi smart EV charger put 48.1kWh of solar energy into our CUPRA Born😎

I was at a friends house yesterday. We both have almost south facing solar arrays, mine is 6.6kW and his 14kW. The main difference between them is that my solar panels are on a 50° roof and his roof is much shallower. I was interested to know how much difference the roof angle is making, so we compared some real-world numbers. Typically he generates 200% as much power as I do, as you would expect.

My 50° roof angle is making a big difference over winter and the peak output of my friends panels have been closer to 150%, a bigger difference than I was expecting. His 3-phase inverter is not limiting his power output but my microinverters limit mine to 6.0kW. I've seen a peak power output of 5.0kW this month.

I found this really useful perfect inclination calculator and this explains why I'm doing so well this month.

Kicked off a new project with my son 😎 We are planning to design and build an Open-Source Sports Electric Vehicle (OSSEV).

I happened to spot this effect on the panels this morning. Initially, I thought we had a problem but them I remembered we have a low-profile bathroom vent under this panel 🤣

Some cold weather this coming week, well below freezing.

Fortunately, this is the result of clear skies, so our Solcast forecasts are high 😎

On days like this, I can use the CUPRA Born app to 'pre-condition' the car and this defrosts it and warms it up so that I can drop my wife off at work, knowing I can charge it up free using my Zappi smart EV charger.

I can also use spare solar energy to keep our home warm, using things like my smart oil heater.

In the first 15 days of January my smart home solar installation project has generated just 100kWh, the lowest I've seen in any month.

Fortunately, this is looking like it will double in the coming week, according to my Solcast forecasts 🙂

I have spray painted the main parts of my Vertical Axis Wind Turbine (VAWT) with a white primer, followed by a white gloss paint.

The top plate for my first Vertical Axis Wind Turbine (VAWT) tidied up and ready to paint.

My UNI-T UTi260A thermal imager arrived in the post this morning. I will be reviewing this device when I get back from my skiing holiday.

With the template 3D printed, I roughly cut some 5mm thick aluminium sheet to size using a jigsaw. I'd love a plasma cutter to be able to do this stuff!

This 'top plate' will better support the arms and both vertically and horizontally, as I've added an extra bolt hole.

To strengthen the mounting of the arms for my Vertical Axis Wind Turbine (VAWT), I'm using a 5mm thick aluminium plate to support the 3D printed parts. I 3D printed a template and drill guide for this top plate. All these bits will be spray painted white eventually, to protect them from the elements.