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 Performance Thread - Post your monthly output

championc

I think it would be very useful to post Solar PV monthly generation figures. Not only could it highlight a problem further down the road, but there many be many owners who are getting far less than they expected (or promised by an installer) and would welcome feedback from other owners.

Of course, there are so many factors involved. Your location in the country (or abroad for our international boardies), your array size, your array direction and the panels mounting angle.

Find more posts tagged with

Quick Links

Comments

championc

DrPhilG wrote: »

How did you manage to export anything given that you have such a big battery?

I'm considering a change in the future from my Pylontech batteries, to a DIY build using recycled Leaf cells. I could switch from the 4.8kWh PylonTech I have, to about 6kWh of Leaf battery without much extra cost as I can sell the PylonTechs to fund the cells, BMS & install. I would then be able to expand that DIY system for a cost of around €60/kWh rather than about €330/kWh to add more PylonTech 2.4kWh modules.

Good spot !!! My batteries are Lead-Acids - so you only have about 50% of usable storage at best. Lead-acids also have a very shallow curve for charging power above 80% charge, so on a sunny day, my batteries are at 80% by lunchtime. So I've a project now with LiFePO4's

E30M3

Install completed on 5th August so production figures are for 6th 31st Inclusive.

South East
5.6 kw (16 350w panels, 12 East and 4 West facing)

Worst Day 16/08 - 4.2 Kwh
Best Day 08/08 - 29.9 Kwh

Overall 429.8 for the 26 days for average of 16.53 Kwh per day.

Still learning re maximising usage etc but the priority for me this month was to see the generation which seems right in line based on other folks figures.

unkel

DrPhilG wrote: »

Ps who's hot and who's not at the minute for electric suppliers? My SSE deal is ending soon.

My contract is up in 2 weeks time, I checked yesterday and Energia has by far the best rates for electricity.

I renewed my gas with Flogas today. They offered me the best deal in the market. Quite refreshing. I wouldn't be having to switch providers every year if my current provider just gave me the best deal available in the market. So fair play to Flogas. Saved me a bit of hassle.

DrPhilG

Yeah looking like a return to Energia for me.

Although I just double checked and my 12 months isn't up until November so things might change.

Winterman1234

The new company bright seem very good as well, with a good rural standing charge.

graememk

DrPhilG wrote: »

Yeah looking like a return to Energia for me.

Although I just double checked and my 12 months isn't up until November so things might change.

Winterman1234 wrote: »

The new company bright seem very good as well, with a good rural standing charge.

Yeah once most of your "day" useage is covered via solar, the standing charge will come into account much more than just the cheapest unit rates

Winterman1234

graememk wrote: »

Yeah once most of your "day" useage is covered via solar, the standing charge will come into account much more than just the cheapest unit rates

Yes indeed during April/May billing period I averaged out at 2.6 units daily, so standing charge was as much per day.

MAULBROOK

DrPhilG wrote: »

Yeah looking like a return to Energia for me.

Although I just double checked and my 12 months isn't up until November so things might change.

Stay away from Electric Ireland, low usage charges. Not good for a solar setup

Nelbert

Does anyone have a full year usage Vs previous year?
Be interested to see how much is saved off electricity bills when you average over the year.
We're above average elec consumers so would be good to see some of these impressive generation and reduced grid figures put in to the context of annual bill totals if anyone can?

championc

Nelbert wrote: »

Does anyone have a full year usage Vs previous year?
Be interested to see how much is saved off electricity bills when you average over the year.
We're above average elec consumers so would be good to see some of these impressive generation and reduced grid figures put in to the context of annual bill totals if anyone can?

You could just simply take people's generation minus any exported power, and multiply by about 20c per kw. So that's the absolutely maximum saving. Many of us are saving power to batteries and using up power to diverters, so possibly multiply your figure by about 0.7 to get a more real figure.

garo

Nelbert wrote: »

Does anyone have a full year usage Vs previous year?
Be interested to see how much is saved off electricity bills when you average over the year.
We're above average elec consumers so would be good to see some of these impressive generation and reduced grid figures put in to the context of annual bill totals if anyone can?

I can give you my totals. I used 5300 kWh the year before. Because we are working from home this year, our usage was higher at 5600 kWh in the last 12 months. With a 4.8kW system we imported 2550 kWh in that period.

Nelbert

garo wrote: »

I can give you my totals. I used 5300 kWh the year before. Because we are working from home this year, our usage was higher at 5600 kWh in the last 12 months. With a 4.8kW system we imported 2550 kWh in that period.

Wow. So despite increased usage you've still saved a significant chunk off your electricity bill.
My current usage is a bit higher than yours so I could potentially see similar returns.

garo

3050kWh is ~490E at day rates. Assume some of this could be substituted with night time electricity. My estimate was 420 without WFH so I think it was a good guess. I have a 4.8kW system and one 2.4kWh pylontech battery.

DrPhilG

I'm averaging about 2kWh of day time purchase since install in late July. And that includes doing 90% of the washing and drying etc during the day that we used to do at night.

Buying 5-6kWh per 24 hours on average.

6kw system with a 4.8kWh battery though.

phester28

Not sure how I'm doing so far. Fist month end since commissioning

Location Cork

2.4KWP 1.5 east 900w West 25deg pitch (estimate)

That's 85.4 Kwh from the 18th of August to 31st of August.

By averaging and applying this for the missing days that would give me 190Kwh for august. Which is way less than the estimate of production given by the PVGIS software

Is there anyone with a similar size setup or similar location that I can use going forward to get a handle on comparisons

championc

phester28 wrote: »

Not sure how I'm doing so far. Fist month end since commissioning

Location Cork

2.4KWP 1.5 east 900w West 25deg pitch (estimate)

That's 85.4 Kwh from the 18th of August to 31st of August.

By averaging and applying this for the missing days that would give me 190Kwh for august. Which is way less than the estimate of production given by the PVGIS software

Is there anyone with a similar size setup or similar location that I can use going forward to get a handle on comparisons

Are your panels on two separate strings into the inverter, or do you have optimizers fitted ?

phester28

Its a dual string inverter so they are both separate strings

garo

August was bad. I got 420 kWh from my 4.8kWh system. similar slope to yours 100/280 even split. What is you E/W angle. Since you have more of your panels on the East cloudy morning will ruin it for you.
Also is there any shading from chimneys or neighbour's roof or trees?

phester28

from what i can tell im the panels are almost true east -west. If i can trust google maps. No shading issues.

So far my best peak production (all be it brief) Was 29/8/20 where i got 1910W 149V 9.8A on the east and 91V 6.2A on the West at noon.

championc

phester28 wrote: »

from what i can tell im the panels are almost true east -west. If i can trust google maps. No shading issues.

So far my best peak production (all be it brief) Was 29/8/20 where i got 1910W 149V 9.8A on the east and 91V 6.2A on the West at noon.

It could be that 3 panels on one string is a bit too light, especially on semi cloudy days. The spec sheet for your inverter should confirm one way or another

garo

Good point. Maybe the three panels aren't enough to drive that string in heavy cloud or early morning and evening.

phester28

All ok on that front. The MPPT has a 60V start and will regulate down to 50V

See my west facing (PV1) starting to make voltage at around 7am (diffused light day)

East string is at 133V when west is at 79V at 7am

west dips slightly (i assume mppt?) and east continues to grow (more light?)

denismc

I have 2.08kWp south facing in Cork and from 18th to 31st of August I generated 110 kWh, total for August is 232kWh.
I would have thought East-West facing panels would produce a bit less than south facing!

garo

Yes a bit but the difference is not that large during the summer. It depends on the slope of your roof etc. But April to August the sun usually gets high enough in the sky that both sides get sunshine for most of the day.

Winter is a different story. I was getting 5kWh on sunny days in Dec when others here with similar sized south facing arrays were getting 14.

Gumbo

August.

279 kWh

3kw system, south facing in North Dublin.

Duine_Eigin

Gumbo wrote: »

August.

279 kWh

3kw system, south facing in North Dublin.

This is reassuring to see. I have a similar 3kW system south facing in North Dublin and my output for August was 272kWh. I thought there was something wrong with my system as I was comparing this 2020 August figure to the 2019 August figure of 354kWh. Seems like we just got a lot less sun this summer.

After good outputs in the months of April and May, figures have been down in June, July and August.

Month / 2019 / 2020
April / 284 / 371
May / 358 / 509
June / 361 / 306
July / 376 / 317
August / 354 / 272

Gumbo, are your output figures for this year similar to mine above?

DrPhilG

A day and a half left til the monthly figures are complete, but I just hit my monthly prediction of 429kWh with time to spare.

Prediction for August was 601.4kWh and I fell short by 5%.

championc

DrPhilG wrote: »

A day and a half left til the monthly figures are complete, but I just hit my monthly prediction of 429kWh with time to spare.

Prediction for August was 601.4kWh and I fell short by 5%.

Have you a link to the predictor ?

garo

https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html#PVP

Tool for calculating output.

graememk

garo wrote: »

https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html#PVP

Tool for calculating output.

Oh thats a nice tool!, what GIS database do you use/find more accurate?