nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

Child Item

Solar PV Hints, Tips & Troubleshooting

DrPhilG

Well I've reached the point of driving everyone nuts on the PV quotes thread, and since I now have my system installed and running my endless questions no longer belong there.

So I figured I'd ask here, and also provide a home for others in the same boat, with general questions and advice on managing post-install.

My first question (of many) is how do people best manage their production in order to reduce grid export? Despite being overcast and miserable a fair bit of the day, I've produced 24kWh so far today, but ended up exporting 11.

Not too bad when we're home, as the wife did a few loads of washing and drying, put on the dishwasher etc.

But we're both at work tomorrow so other than a timed or remotely activated washer/dryer run we would end up exporting a lot more.

Extra battery capacity or a water diverter would help, but they don't tend to justify their costs in the long term.

Find more posts tagged with

Quick Links

Comments

DrPhilG

Since installation on Wednesday of last week my average day time usage has dropped from 12kWh average, to 3.75.

Night usage average down from 22kWh to 15 and the only reason it's still that high is because I had a lot of driving this past week and put about 45kWh into the car.

Once the Zappi & Eddi are up and running, I reckon I'll drop that to

daytime and <10 night.

DaveyDave

KCross wrote: »

That’s a small system. It will only primarily cover background load.

I wouldnt waste your time trying to manually manage the little excess you will have from it.

turning on things like immersions or dryers etc would consume multiples of what that system would produce.

Do you have night rate electricity? If not, then maybe turn on a wash or dryer while the sun is shining but don’t go OCD on it as the savings will be small. If you do have night rate electricity then you should be using that for your appliances rather than trying to second guess the cloud cover.

We don't have night rates. I know it's a small system but is there really no use in it apart from idle load?

Yesterday morning was a steady 700w, surely that would be of some benefit to something like the dishwasher? I'm not going to be checking the weather forecast to use the washing machine on a sunny morning but something we use daily like the dishwasher, rather than putting it on in the evening when there's no solar, might as well put it on in the morning on the chance there's decent sun? If there's no sun at the very least it frees up any potential solar in the afternoon/evening.

KCross

DaveyDave wrote: »

We don't have night rates. I know it's a small system but is there really no use in it apart from idle load?

Yesterday morning was a steady 700w, surely that would be of some benefit to something like the dishwasher? I'm not going to be checking the weather forecast to use the washing machine on a sunny morning but something we use daily like the dishwasher, rather than putting it on in the evening when there's no solar, might as well put it on in the morning on the chance there's decent sun? If there's no sun at the very least it frees up the electricity in the afternoon/evening when usage is higher.

As I said, turn on appliances while the sun is shining but the savings will be small so don’t go OCD on it.

DrPhilG

Any experts on the myenergi products here? There is at least one I believe, assuming it's the same guy with the same username who posts on the myenergi forum.

I've posted on there, but I figured I should do so here too in case anyone else has similar issues.

So my deal is that I've got a 6.2kw system with a 5kw Solis Hybrid inverter and 4.8kWh pylontech batteries. Also have a Zappi 2, Eddi, Harvi & Hub.

Last week after my installer came for a second visit, everything seemed to be fine. The car was happily only charging on excess, after the battery was full. I realise that the battery is DC coupled and therefore the CT clamp can only read the data on the house side of the inverter, which should in theory mean that the battery will always take priority and the Eddi/Zappi can only use whatever excess is actually going to the grid, that's fine with me.

Well today I came home at 1pm. Battery was at 98%, Eddi was already full from earlier on, and production was at around 2kw with consumption around 500w. So I plugged in the car, with the expectation that it would charge while excess was above 1.4kw.

So I was a bit baffled when the car immediately started charging at about 2.7kw and according to the Solis app, it was using the 1.4kw excess plus another 1.3 from the battery.

It actually peaked later at 3.7kw with 2.3 coming from the battery.

So my question is, how the hell did that happen? If the Zappi only reads available solar as the figure coming out of the inverter AFTER it has charged the battery, then as far as the Zappi was concerned, it was pulling from the grid which it shouldn't do.

Some googling told me that there is a setting in the Zappi to make it only activate a charge once there is a certain amount exporting to the grid, the "export margin" setting which should be set to 100w. This would ensure that the charge only initiates if there is shown to be an export occurring.

However I'm not sure that this will work, since there was an export happening today when the Zappi started. The problem was that it took the excess which is should have taken, but also demanded more power which therefore came from the battery.

I suspect that my installer may still have his clamps in the wrong place/setup. Myenergi CT clamping seems to be a mystery to many installers. Mine called the myenergi helpline on the phone to get things done right but I still think they might be off.

Currently (to my knowledge) there is a CT clamp on the main line in from the meter. That is hard wired using cat-5 from there directly to the Zappi. There is also a hard wired connection from a second CT clamp, on the AC side of the inverter which shows on the Zappi as "Generation".

The Harvi is fitted inside the meter box and clamped onto the main line.

Now here's the question. Where does the Zappi get its figures on export? I would have thought it would be in from that clamp on the main line that is hard wired, or from the clamp connected to the Harvi.

Next up, the Harvi doesn't seem to be paired to the Zappi. It doesn't show on the paired devices section, but it does show in that section on the Eddi. I do realise that the Harvi may not even be required since the Zappi is hardwired but I got a good deal on all the equipment so took the Harvi too.

Thoughts?

thos

The export margin should resolve your issue, it means it will never use all available power but instead ensure there is always a safety margin of that much, so it stops the battery kicking in trying to supply power where it thinks there is a deficit.
Start with 100w but you may need to try a bit more. Also ensure you’re Eco+ is at 100%

DrPhilG

thos wrote: »

The export margin should resolve your issue, it means it will never use all available power but instead ensure there is always a safety margin of that much, so it stops the battery kicking in trying to supply power where it thinks there is a deficit.
Start with 100w but you may need to try a bit more. Also ensure you’re Eco+ is at 100%

1 - I don't mind the battery supplying a little deficit. Given that the Zappi needs 1.4kw to start, I wouldn't mind topping it up a bit rather than potentially losing 1kw an hour. Would the export margin combined with an 80% setting on eco+ allow that?

2 - I don't have the export margin setting where I should have.

I should have something like this (from Google images)

thos

Very strange.
Do you know what firmware version your on?

Other option is talking to MyEnergi direct, I’ve talked to them a few times, found them very helpful.

DrPhilG

I've made contact with one of their tech folk on their forum, fingers crossed.

Incidentally I found the export margin setting. Because the Eddi is set as master, the setting is present there rather than the Zappi.

And today it seemed to work correctly, perhaps because I set the margin to 100w.

Typically the sun was scorching down all day, battery was full by lunchtime and despite the washing machine and dishwasher both doing a cycle, I still exported 5kWh by 4pm.

Got home from work at 5 and the clouds had rolled in thick and fast and production was down to below 1kw. So I only had about 400w spare.

I plugged in the car, and it sat on "waiting for surplus". Meanwhile the Eddi soaked it up instead.

Of course what I needed to test the theory was for the excess to get over 1.4 and see if the Zappi would then engage, and at what level. But the sun was done for the day.

I'll update here with whatever the myenergi guy advised too.

daughy

Hi Phil, I have seen on an Irish website for an install of a zappi for 650 after grant, I understand you actually have to have an electric car before you apply for the zappi grant?
Is this correct?

daughy

Also, I have read your posts from another thread, is it advisable to install a large system if your exporting alot of it back to the grid.
I myself didn't get a grant, was a DIY install.
I'll be going for an extra 5, 350 watt panels, 10 West, 5 South.

DrPhilG

daughy wrote: »

Hi Phil, I have seen on an Irish website for an install of a zappi for 650 after grant, I understand you actually have to have an electric car before you apply for the zappi grant?
Is this correct?

Yeah you do need to have the car I believe. I've had mine for years so it was straightforward.

DrPhilG

daughy wrote: »

Also, I have read your posts from another thread, is it advisable to install a large system if your exporting alot of it back to the grid.
I myself didn't get a grant, was a DIY install.
I'll be going for an extra 5, 350 watt panels, 10 West, 5 South.

If you're going to be exporting a lot, then don't waste the money on extra panels.

I installed 20 panels because I have a very high use house and bills averaging about €130 a month.

Even then with 6kWp I managed to export 200kWh between August and September.

daughy

DrPhilG wrote: »

If you're going to be exporting a lot, then don't waste the money on extra panels.

I installed 20 panels because I have a very high use house and bills averaging about €130 a month.

Even then with 6kWp I managed to export 200kWh between August and September.

That's is alot, that's more than I made in September. My electric bill can go into the 700 used for the two months, if I can try and offset that I will. Only made 200kw in September so hopefully the extra 5 panels at 3.5kw west and 1.75kw south should boost the crap out of this. I prefer to have the west panels now as it'll give power to the Eddie when I get it as my hot water tank is the old copper cylinder and doesn't keep the water hot for too long. I'll invest in the future in a insulated stainless steel tank.
Your system looks great though. Nice 1

unkel

daughy wrote: »

Hi Phil, I have seen on an Irish website for an install of a zappi for 650 after grant, I understand you actually have to have an electric car before you apply for the zappi grant?
Is this correct?

Yes. And you could get a cheaper (second hand) charge point for about 0 after grant. The extra 650 for the Zappi will never pay for itself, even if you hook your car up to it every day

Nice idea to charge your car up from the sun at your own gaff, totally zero emissions, but there is a price to be paid for doing this

daughy

unkel wrote: »

Yes. And you could get a cheaper (second hand) charge point for about 0 after grant. The extra 650 for the Zappi will never pay for itself, even if you hook your car up to it every day

Nice idea to charge your car up from the sun at your own gaff, totally zero emissions, but there is a price to be paid for doing this

That's true unkel, I have thought also about the longevity of myenergi, if they go out of business does that app stop working? Also does the zappi not do what every other car charger does? If your over producing your car charger will send that to your car anyway? Is the zappi worth it? I'm still thinking about it. If I'm going to add up to 5.25kw of panels I definitely need a dump load as I don't have batteries, just in limbo at the moment. My eyes are bigger than my belly at times. I have 5 adults at home so alot of showers,if I at least get an Eddie to monitor the incoming solar and hot water I'll at least have accomplished 2/rds of my goal.. I have an old gas fire back boiler system to heat the water, if I can cut the costs from let's say may till October, would that not pay for itself over time?

But then again you need a harvi, and a hub, and an extra ct Clamp, so I'm the region of 700?

I saw an Eddie on an Irish website for approx 485.. I know it's expensive but can anyone else vouch for it here? Is it worth that?

daughy

Then again I did see a device for monitoring your solar and grid for 40 euro, its called a shelly em smart energy monitor.

DrPhilG

unkel wrote: »

Yes. And you could get a cheaper (second hand) charge point for about 0 after grant. The extra 650 for the Zappi will never pay for itself, even if you hook your car up to it every day

I've had a Rolec for 5 years and then a Zappi 2, total cost for purchase and installation of both, about €600.

Thats not quite unkel levels of bargain, but its not bad.

garo

A Zappi would save you 8c per kWh - going on night rate. And an Eddi would save you 5c going on how much it costs a boiler to heat water. If I were you I would put your money into getting a factory insulated cylinder before either a Zappi or an Eddi. You will make your money back faster. I went from an uninsulated copper cylinder with a lagging jacket falling to pieces and no heating zones or control to an insulated cylinder and a thermostat controlled hot water system. Saving about 100 a year on the gas bill I reckon.

sphinxicus

daughy wrote: »

Then again I did see a device for monitoring your solar and grid for 40 euro, its called a shelly em smart energy monitor.

yes i've done a lot of reading about the shelly device for this and had intended on grabbing one to use with Home Assistant to log my energy usage over time so i would have a better idea of what size system i should go for and at what time of the day my usage peaks etc. Sadly i wouldnt have a clue how to wire the thing into my consumer unit to monitor the whole house usage and getting a spark out to do such a small job seems to be a no-go. So its just been a pipe dream until somebody posts a step by step guide for dummies on a leccy system that aint in the US

daughy

garo wrote: »

A Zappi would save you 8c per kWh - going on night rate. And an Eddi would save you 5c going on how much it costs a boiler to heat water. If I were you I would put your money into getting a factory insulated cylinder before either a Zappi or an Eddi. You will make your money back faster. I went from an uninsulated copper cylinder with a lagging jacket falling to pieces and no heating zones or control to an insulated cylinder and a thermostat controlled hot water system. Saving about 100 a year on the gas bill I reckon.

I had a chat with a plumber in work and said he will install a stainless steel tank for me for 700.
I have the same copper cylinder you used to have, old lagging jacket. Temp drops very fast. I know the right thing to do is get the hot tank upgrade first. It's a no brainer. Wish I just won that bloody lottery ha.

daughy

sphinxicus wrote: »

yes i've done a lot of reading about the shelly device for this and had intended on grabbing one to use with Home Assistant to log my energy usage over time so i would have a better idea of what size system i should go for and at what time of the day my usage peaks etc. Sadly i wouldnt have a clue how to wire the thing into my consumer unit to monitor the whole house usage and getting a spark out to do such a small job seems to be a no-go. So its just been a pipe dream until somebody posts a step by step guide for dummies on a lexxy system that aint in the US

I understand, I can't justify paying a spark for such a small job either. I'm guessing it would just need a 6amp breaker, something your light switch uses, it's the same for the Solis hybrid meter, I still haven't installed it to the main board to monitor my grid usage, I am still non the wiser as to what exactly its used for other than monitor your grid, I think it's an export meter. I don't think I need it as they're is no fit payments anyway

garo

This advice comes with a health warning. You can wire such a device at either the fusebox or the meter. In my house the meter was easier (and safer) but you may have to work around power to the recording device and taking the cable from CT clamp to the device.

You need to identify the main brown wire than is feeding leccy into the house and put the CT clamp around it making sure it is put in the right orientation. The clamps usually have an arrow pointing to the direction current should be flowing in (I.e. to the house).

If you know what you are doing it is a two minute job.

daughy

garo wrote: »

This advice comes with a health warning. You can wire such a device at either the fusebox or the meter. In my house the meter was easier (and safer) but you may have to work around power to the recording device and taking the cable from CT clamp to the device.

You need to identify the main brown wire than is feeding leccy into the house and put the CT clamp around it making sure it is put in the right orientation. The clamps usually have an arrow pointing to the direction current should be flowing in (I.e. to the house).

If you know what you are doing it is a two minute job.

So basically the live and neutral from your light switch circuit breaker to the meter, the circuit breaker is already grounded so that should be fine. But I would ground the meter in any case. I actually bought 30 metres of cat 6 cable for the meter but never got around to the install,
Garo is right though, if your unsure do not try this.

garo

daughy wrote: »

I had a chat with a plumber in work and said he will install a stainless steel tank for me for 700.
I have the same copper cylinder you used to have, old lagging jacket. Temp drops very fast. I know the right thing to do is get the hot tank upgrade first. It's a no brainer. Wish I just won that bloody lottery ha.

What size tank would that be? And I assume the price includes the tank as well? I had a pre insulated copper tank installed for 440 so 700 for a steel tank is not bad. If you have many women in the house make sure you get a large tank. At least 200l and preferably 300l if you have space. For future proofing think about a design that has an immersion going all the way to the bottom. When you eventually get a diverter you would want it to heat the whole tank and not just the top.

garo

daughy wrote: »

So basically the live and neutral from your light switch circuit breaker to the meter, the circuit breaker is already grounded so that should be fine. But I would ground the meter in any case. I actually bought 30 metres of cat 6 cable for the meter but never got around to the install,
Garo is right though, if your unsure do not try this.

Make sure you put the CT clamp around the live ONLY! If you put it around both the live and the neutral you will get a zero reading!

https://youtu.be/ah3ezprtgmc

Here is a video that explains the whole process through doesn’t show the clamp install.

And halfway through this video you have the installation of a CT clamp:

https://youtu.be/l9HUZJkQMKg

daughy

garo wrote: »

What size tank would that be? And I assume the price includes the tank as well? I had a pre insulated copper tank installed for 440 so 700 for a steel tank is not bad. If you have many women in the house make sure you get a large tank. At least 200l and preferably 300l if you have space. For future proofing think about a design that has an immersion going all the way to the bottom. When you eventually get a diverter you would want it to heat the whole tank and not just the top.

I'm about to sell my pc so that will cover the cost of a new tank install.
I'll update you tomorrow when I chat to the plumber. Its for a full install, I'll ask him if he is looking for more business and will give his number in pm if anyone is interested. He's never idle as plumbers are always needed.
I definitely need a tank that can keep the water hot for at least 24 hours as this is just throwing money away.

daughy

garo wrote: »

Make sure you put the CT clamp around the live ONLY! If you put it around both the live and the neutral you will get a zero reading!

https://youtu.be/ah3ezprtgmc

Here is a video that explains the whole process through doesn’t show the clamp install.

And halfway through this video you have the installation of a CT clamp:

https://youtu.be/l9HUZJkQMKg

I appreciate that garo, unfortunately I have the Solis hybrid inverter energy meter, the hybrid inverter can back feed to the grid so you can set the inverter to discharge as much as you see fit when the energy meter is installed. It's only worth something if there is a fit rate.
Has anyone else installed or had installed this meter to they're main board? Would be nice to see a picture of the wiring.

garo

daughy wrote: »

I appreciate that garo, unfortunately I have the Solis hybrid inverter energy meter, the hybrid inverter can back feed to the grid so you can set the inverter to discharge as much as you see fit when the energy meter is installed. It's only worth something if there is a fit rate.
Has anyone else installed or had installed this meter to they're main board? Would be nice to see a picture of the wiring.

I don't understand. What does the brand of the inverter or whether you export to the grid have to do with CT clamp installation? I linked the second video only to show how a CT clamp should be connected. Ignore the first half of that video.

garo

daughy wrote: »

I'm about to sell my pc so that will cover the cost of a new tank install.
I'll update you tomorrow when I chat to the plumber. Its for a full install, I'll ask him if he is looking for more business and will give his number in pm if anyone is interested. He's never idle as plumbers are always needed.
I definitely need a tank that can keep the water hot for at least 24 hours as this is just throwing money away.

Ouch sorry you have to sell your PC to fund this.

daughy

garo wrote: »

I don't understand. What does the brand of the inverter or whether you export to the grid have to do with CT clamp installation? I linked the second video only to show how a CT clamp should be connected. Ignore the first half of that video.

I kinda knew you where getting at that when i watched the video, miscommunication, I'm looking to install an energy meter to the main board. I built the pc myself, a gaming pc, but hanvnt used it in 6 months. Must be getting old.