Daily pv production

tails_naf

championc wrote: »

I think your Red are the 3 panels East and the Blue is the 5 panels West, based on your graph. However, what I don't understand is the Yellow. I cannot see how the yellow can be so high in the morning unless, have you a battery too ?

When DC volts is lower than AC, the inverter has to work much harder to upscale than it would to downscale. So 1kW @ DC 100v = less than 0.5kW @ AC 230v

Also, at 85v, you might well be right on the threshold of the inverter being able to run. Ideally, you want strings with DC volts higher than the AC volts. What model of inverter have you got ? What is it's stated DC Input range ? It could be that it's generating nothing from the 3 panels string because the power is too low.

Have you a DC voltage graph ?

Here's a plot from a 4.5kwp system today (not mine, but one I've web access to). It maxed out at around 1.5kw, or 33% of peak, a s 5kwh for the day.



I've also added the DC voltage, which should ideally be flattish as you can see here when the panel is capable of producing. The operating voltage is a function of the number of panels (around 30-35 odd volts per panel, typically). In fact, the number I'm seeing here of 250 volts is for one string of 7x320w panels. It would be interesting to see what voltage you are seeing on each string.

phester28

Sorry I did not want to overcrowd the graph so I omitted the Voltage as that (under normal circumstances) is well understood.

voltage.png



@tails I see from graph your peak current was over 5 amps. If this is south facing then its not a fair comparison. I think?

DrPhilG

Seems like the curse of 2020 extended beyond Covid.

Since Christmas:
25th - 1.1
26th - 0.5
27th - 1.5
28th - 0.5
29th - 2.0
30th - 3.7
31st - 1.3

Average - 1.51kWh


Since 2021 kicked in:
1st - 2.4
2nd - 5.2
3rd - 5.5
4th - 2.8

Average - 3.97kWh

And the forecast is for sun all week.

graememk

DrPhilG wrote: »

Seems like the curse of 2020 extended beyond Covid.

Since Christmas:
25th - 1.1
26th - 0.5
27th - 1.5
28th - 0.5
29th - 2.0
30th - 3.7
31st - 1.3

Average - 1.51kWh


Since 2021 kicked in:
1st - 2.4
2nd - 5.2
3rd - 5.5
4th - 2.8

Average - 3.97kWh

And the forecast is for sun all week.

except for the snow tomorrow! It is January!

tails_naf

phester28 wrote: »

Sorry I did not want to overcrowd the graph so I omitted the Voltage as that (under normal circumstances) is well understood.

voltage.png



@tails I see from graph your peak current was over 5 amps. If this is south facing then its not a fair comparison. I think?

Thats true, thst was from a South facing system. I've also a 6 panel WSW set of panels and the current from that is shown here

So still getting to 5A peak output when the sun hits it right. It gets hit by some shading right after the peak and that kills it, so do you have much shading?

mp3guy

Back on the increase, 25.4kWh today (5.76kWp SSW, 4.48kWp ESE). Can I break 100kWh in Summer?

slave1

Well if you’re getting that on a short day and low angle sun then why not, I’d be delighted for you if you did.
We should have a highest daily production thread

DrPhilG

Crappy day today, worst of the month at 1.9kWh.

Still, 33kWh for the month so far so well ahead of December's averages.

With the savings compared to last year sitting where they are, I reckon I should be on course for about €800-900 saved in the first year.

Gumbo

8.8 kWh today.
4.7kw system (3 south and 1.7 north).

I’m still waiting on my battery install and I’m still trying to figure out the GivEnergy portal.
It states my consumption today was 22.5kwh but I noticed that when my eddi is diverting to the immersion the GivEnergy portal picks this up as a house load.

mp3guy

Gumbo wrote: »

It states my consumption today was 22.5kwh but I noticed that when my eddi is diverting to the immersion the GivEnergy portal picks this up as a house load.

That makes sense. All the Eddi does is watch your solar production and house load (also grid export) and once there's a surplus that would otherwise go to the grid, it provides power to your immersion, which comes off your main consumer unit, hence house load.

graememk

Gumbo wrote: »

8.8 kWh today.
4.7kw system (3 south and 1.7 north).

I’m still waiting on my battery install and I’m still trying to figure out the GivEnergy portal.
It states my consumption today was 22.5kwh but I noticed that when my eddi is diverting to the immersion the GivEnergy portal picks this up as a house load.

Yeah unless it has a way of monitoring the immersion, It cannot tell the difference if the eddi is running or not.

All it has is the solar generation and the import/export to work out the house useage.

Does the eddi just have a CT on the main tails or does it have one on the solar too? if it has both, the myengeri system could be the best way for you to monitor stuff as it knows more about your system... but it will see useage from the battery as solar generation. (which it technically is)

unkel

Gumbo wrote: »

1.7 north

Pure north? New string in your setup? What's the angle if you know? You're probably the first in the forum with a north facing array, fair play!

I've a nice virgin pure north facing roof, waiting to be plastered with solar PV, keeping a keen eye on any relevant comments.

slave1

My Northish facing second string have been frozen white for the last week so can’t imagine them generating anything this time of the year

BrendanD

I just got the solar as a service installed on 22December 7 panels no battery south facing no shade ; generating an average of 2.20 kwh per day .
Was wondering if anyone else here has this and if they have an Eddi installed ? Is it worth it ?
Also have the room to install another panel so hoping to get that done soon

unkel

No, not worth it. The Eddi will be long dead before it will have paid for itself. On a 7 panel system about 15-20 years. And that is without a feed in tariff. If we ever get one it will make zero sense to even have an Eddi

idc

unkel wrote: »

No, not worth it. The Eddi will be long dead before it will have paid for itself. On a 7 panel system about 15-20 years. And that is without a feed in tariff. If we ever get one it will make zero sense to even have an Eddi

If your only water heating is electric immersion would an eddie not make sense?



Would it make sense if the feed in tariff is low such as that you'd be better off using surplus PV heating water vs using gas ? Or if gas and carbon taxes increase over time?

mp3guy

unkel wrote: »

No, not worth it. The Eddi will be long dead before it will have paid for itself. On a 7 panel system about 15-20 years. And that is without a feed in tariff. If we ever get one it will make zero sense to even have an Eddi

If making your money back on the purchase is your only measure of "worth it".

It can do more than just divert excess like an iBoost. Has a nice app, so you can "turn on the immersion" from your phone whenever and control priority w.r.t. your Zappi if you have one. Myenergi are rumored to be working on a battery also which would allow priority control with that too.

It also has dual power outputs, meaning you can connect not only a single immersion, but also some other sort of resistive load heater, e.g. a space heater that automatically comes on for sunny but cold days.

unkel

Yeah that feature is cool, but you'll agree with me that having a company install an Eddi (for about €500 all in) is an unwise move from a financial point of view. If you can buy one second hand and install DIY, it might start to make sense. And of course a lot of what many of us do in here is more of a hobby and moving away from burning fossil fuel and using renewable electricity instead is always a good thing

unkel

idc wrote: »

If your only water heating is electric immersion would an eddie not make sense?

It would be a bit less foolish. But heating your water with immersion at night rate only costs 7c / kWh. Not an awful lot more than heating your water with a very efficient gas boiler (about 5c / kWh)

And if we get a FIT, even as low as 5c / kWh, not sending back excess production to the grid would be financially foolish. In fact I plan to install a whole load more of PV once FIT comes in as it has a very nice return on investment compared to say having your money in a savings account

championc

BrendanD wrote: »

I just got the solar as a service installed on 22December 7 panels no battery south facing no shade ; generating an average of 2.20 kwh per day .
Was wondering if anyone else here has this and if they have an Eddi installed ? Is it worth it ?
Also have the room to install another panel so hoping to get that done soon

Bare in mind too that a 2.1kWp system won't be generating massive amounts of excess.

What's your base load level ?

Gumbo

graememk wrote: »

Yeah unless it has a way of monitoring the immersion, It cannot tell the difference if the eddi is running or not.

All it has is the solar generation and the import/export to work out the house useage.

Does the eddi just have a CT on the main tails or does it have one on the solar too? if it has both, the myengeri system could be the best way for you to monitor stuff as it knows more about your system... but it will see useage from the battery as solar generation. (which it technically is)

I’ll try get some more info when they are back to do the battery. I’ll ask if there’s a better way to monitor it.

I’m trying to decide if I should allow the excess to heat the water before diverting to the battery which I think will be the current default set up based on the portal seeing the eddi diversion as a load anyway.

unkel wrote: »

Pure north? New string in your setup? What's the angle if you know? You're probably the first in the forum with a north facing array, fair play!

I've a nice virgin pure north facing roof, waiting to be plastered with solar PV, keeping a keen eye on any relevant comments.

Yes, it’s due north. Added the 1.7kw just before Christmas. 5x340w panels. We were supposed to do 6 but it was too tight to the boundary to get the last panel on.

I’m not sure if I can monitor how the north facing array is working relative to the south facing though.

championc

Gumbo wrote: »

I’m not sure if I can monitor how the north facing array is working relative to the south facing though.

You may need to dive into history stats but it will be recorded, assuming it's on it's own string.

graememk

Gumbo wrote: »

I’m trying to decide if I should allow the excess to heat the water before diverting to the battery which I think will be the current default set up based on the portal seeing the eddi diversion as a load anyway.

You might not be able to make the eddi take the excess first, as the excess is going to be taken by the battery before it even leaves the hybrid inverter,

Ie if the house load is 500, panels are producing 1000, so 500 excess, the inverter will see that first and put that into the battery.

What the Eddie will see is that the panels are producing 500w and the house is using 500w.

If the battery was a completely separate device I think priority can be done there , but that's a separate inverter etc.

mp3guy

graememk wrote: »

You might not be able to make the eddi take the excess first, as the excess is going to be taken by the battery before it even leaves the hybrid inverter,

Ie if the house load is 500, panels are producing 1000, so 500 excess, the inverter will see that first and put that into the battery.

What the Eddie will see is that the panels are producing 500w and the house is using 500w.

If the battery was a completely separate device I think priority can be done there , but that's a separate inverter etc.

All depends on your inverter. Mine has a mode where it serves the house load first (including stuff like Eddi), then fills the battery.

championc

mp3guy wrote: »

All depends on your inverter. Mine has a mode where it serves the house load first (including stuff like Eddi), then fills the battery.

Gumbo wrote: »

I’m trying to decide if I should allow the excess to heat the water before diverting to the battery which I think will be the current default set up based on the portal seeing the eddi diversion as a load anyway.

The problem is that an Eddi purely operates by watching for excess going to the grid. It is not in any way interested or concerned with what might be generated by solar. Solar generated power would only be looked at by a Zappi, if it was required to run in the ECO modes.

The only way to "fool" an inverter would be to use the Eddi Boost option, to "force" it to start heating, and therefore using electricity.

mp3guy

championc wrote: »

The problem is that an Eddi purely operates by watching for excess going to the grid. It is not in any way interested or concerned with what might be generated by solar. Solar generated power would only be looked at by a Zappi, if it was required to run in the ECO modes.

The only way to "fool" an inverter would be to use the Eddi Boost option, to "force" it to start heating, and therefore using electricity.

? The Eddi has two CT clamps, one can go on the grid and one can go on your solar, see page 21 here.

graememk

mp3guy wrote: »

? The Eddi has two CT clamps, one can go on the grid and one can go on your solar, see page 21 here.

Yes but that still only measures what comes out of th inverter,

House use = solar output +(±import/export)

If the excess is getting nabbed by the battery before it even leaves the inverter it's never seen by the Eddie.

Unless your battery is a separate entity. Then the Eddi can measure that and prioritise according

BrendanD

championc wrote: »

Bare in mind too that a 2.1kWp system won't be generating massive amounts of excess.

What's your base load level ?

Yes that’s true am lucky as there’s always someone in the house in the day time so have no problem Usein up what’s produced. Am also in the process of switching suppliers to Energia and made a considerable savings from my old supplier.
I was thinking about the Eddi I was going to install this myself best price I saw was €360 but just wanted to see if that made sense.

Gumbo

mp3guy wrote: »

All depends on your inverter. Mine has a mode where it serves the house load first (including stuff like Eddi), then fills the battery.

It’s GivEnergy Invertor.
Battery has yet to be installed.

Gumbo

BrendanD wrote: »

Yes that’s true am lucky as there’s always someone in the house in the day time so have no problem Usein up what’s produced. Am also in the process of switching suppliers to Energia and made a considerable savings from my old supplier.
I was thinking about the Eddi I was going to install this myself best price I saw was €360 but just wanted to see if that made sense.

If fitting yourself then I think it’s a bit more plausible.
I understand the pay back etc but sometimes it’s just about using the generated power.

I think a 2.1kw system will generate excess as the base loads ina. Typical house should only be around 2-400w.