Solar for Beginners [ask your questions here]

graememk

It does wor

https://www.boards.ie/discussion/comment/122398164#Comment_122398164

It does work. Although I don't think our regs allow it.

Efixx video: our regs usually are similar-ish to the UK

https://youtu.be/4tifYMNWcvg?si=sn6PCjXzHGytkPBL

...Ghost...

https://www.boards.ie/discussion/comment/122371788#Comment_122371788

OK, so because you currently use below the average electricity (4,200kWh per year) it makes more sense to just export the extra generation. Assuming your electric price is about 20c per unit, you are currently spending about €800 plus €250 standing charge = €1,050.

However, you will be getting an EV, so this could change things. How many km do you do per year? You might at the very least consider moving to a night rate electricity. This worked out well for us, even when doing 10k per year in our Leaf and shifting the washing machine and dish washer to night time use.

For a car example;

I do 25k per year in a Tesla Model 3. I get ~13km per kWh. That's 1,920kWh per year. So, about half your yearly house load.

On standard electric costs of around 25c per unit, that's €480. (so less than petrol/diesel at least).

If you switched to night rate, the unit cost would be about 15c, so fuel cost would be €290. Your standing charge goes up by about €100, but is offset by load shifting.

If you had a smart meter, you could top up the car at lower rates. For example, Energia 2-6am at 7.5c = €144 on EV charging for the year.

HOWEVER, back to the house……from 6am - 2am the rate would be much higher at 34c. Excluding the EV, it's safe to assume that you would be using a good 70% of your home energy on the expensive rate, so if you use 4,000kWh per year on house load, 1,200kWh would be at 7.5c (€90) and 2,800kWh would be at 34c (€1,000) which would be €1,090 for your annual use. With a standing charge, that rounds up to about €1,400 for the year. So, more expensive!!! No Thanks!

This is where a battery makes sense. Ignoring solar generation and removing the car charging from the picture, you use 4,000kWh. That's 11kWh per day. If you buy a 15kWh battery pre-made from the likes of Fogstar in the UK, you would be spending €3,000 for a 15kWh unit instead of paying around €2,500 for 5kWh. I think it's worth €500 to triple the capacity. You could also build your own with a DIY kit for half that price, but let's not stray too far and let's keep it simple.

Here's the benefit. The €1000 you were spending on the 2,800 units will now cost €210, plus the 1200 units @ €90 = €300. Your total home electric cost is now €600 with the standing charge, which is a €450 saving on energy costs.

However (again 😁) You will now be charging 15kWh per night into the battery to use only 11 of them. The extra 4kWh will cost 30c per day, or €110 per year for the extra 1,460kWh. You will be able to export the 4kWh you don't need at the end of the night (lest say between 1am and 2am) at 24c per unit. IOW, you will be credited €350 - €110 = €240 per year. That's on top of the €450 saving which totals a €690 saving per year, bringing your electric bill down to €360 including the standing charge. The savings made because of the battery means it will take 4 years for the ready made battery to pay for itself and thereafter it pays you dividends.

That's not all 😂.

Remember we excluded solar? Everything the solar panels generate will export and pay you 24c at current Energia rates. Mind you, the Pinergy export rate is 25c and the night rate is even lower at 5.5c for a 3 hour period, so that would be even better for you!

Anyway, without knowing exact details, your solar should generate a good 3,000kWh per year. That's €720 worth of export. Keep in mind you are taxed at anything over €400 exported, but that's per person, so adding another name to the bill gives you €800 worth of tax free export. Your solar install will probable take around 6 or 7 years to pay itself back, but after that, your €360 bill becomes a credit of €360.

The above is just one potential outcome and all figures are based on todays prices and tariffs. Welcome to the jungle.

iknorr

Question about the install of a solis invertor.

Looking to install a Solis 5kw invertor in a cloakroom.

It will be behind a door when the door is 90degrees open. ( the install wall is parallel to the open door.)

The instruction manual shows 300mm clearance sides and top, 500mm clearance below, but no limit on the depth.

The depth of the invertor is 249mm. Open door to wall is 300mm so 50mm clearance.

Looking to get the grant so would this be an issue?

MrBusso

*Have moved this to the Solar PV Quotes 2024 Thread*

Trying to navigate my way through a Solar installation and I’ve obtained two quotes so far. Looking for feedback if they are competitive

#1 - €6700

10 panel jingko 435 watt

Sigen Energy Controller Single Phase
5 kW of Inverter Power
Sigenergy
1 x SigenStor EC 5.0SP

Eco-Smart Energy Diverter
3.68 kW eco-smart energy diverter, 230V AC Single Phase, Rated Current - 16A, Standby Power Consumption - 3W

#2 - €6100

10 panels 435 watt jinko .4.5 kw.
5kw dyness battery,
Solis hybrid inverter,

Eddie Water diverter.

Quote #2 includes a battery, however, I’ve seen that this brand isn’t the best so unsure on that.

Also, through space issues with our ongoing extension, we would have to house the unit in the garage. Has anyone any experience of this?

Ta!

iknorr

https://www.boards.ie/discussion/comment/122422923#Comment_122422923

http://davidhunt.ie/solar/

Use that for prices. Its fairly good.

Check the T&Cs document for the battery warranty. (usually hidden away on the manufacteurers website) They monitor temperature, charge and discharge rate to make sure you dont go outside the warranty T&Cs. also cycle. Some claim 10,000 when in reality you are limited to 12MWH of total throughput which is only 3000 cycles and about 4 years of use.

No issue with a garage but just keep the DC cables are short as you can and watch the temperture of the battery ni the warranty terms with regard to winter.

space2ground1

Hi all, can anyone recommend an alternative to the Solis app that will give me widgets on my phone / watch showing daily yield etc?

idc

https://www.boards.ie/discussion/comment/122438401#Comment_122438401

In general there will only be one app that works with your inverter. Some inverters might support 2 different versions of an app - eg old/new version. Or if the inverter is rebadged but still using a common backend it may be possible that a different app is available.
Only other option is things like if you have Zappi/Eddi use the MyEnergi app but that doesn't give full picture if you have DC battery connected to your inverter.

mjatkey

https://www.boards.ie/discussion/comment/122438401#Comment_122438401

There's an APP called SolisQuickView which displays Production and battery if used, you'll need API access from Solis (just apply on their website) and there is of course Home Assistant which is very good albeit there is a fair amount of work to set it up and get it working. (Automation thread is very good on Boards) two months in I'm just getting to grips with it albeit again only using Solis API data, even doing it that way its still very good and there is APP too.

space2ground1

https://www.boards.ie/discussion/comment/122441038#Comment_122441038

I must check that out. I have the API info as I knew I’d need need so that’s a good start. Thanks!

noelfitz

Recently I got solar panels on my roof and an Eddi diverter. With the system I also got two apps on my phone, SolisCloud and myenergi.

In the past I used my gas central heating to heat water, but now the installer changed to Eddi to heat the water, which is too hot.

I would like help in lowering the water temperature and understanding my new system.

Thanks and regards.

Jonathan

https://www.boards.ie/discussion/comment/122466737#Comment_122466737

When you say too hot, it is dangerous? Scalding hot? Does your immersion have a thermostat built in. Most do, and are set at 60°C.

slave1

..and the thermostat will be under a cap on your hot tank with a dial to adjust the heat (downwards in your case)

Emperor Tomato Ketchup

I am looking to get solar panels. At the same time my immersion heater has stopped working. Looks like the element most likely. It's 30+ years old and I'd be thinking of replacing it to get an efficient one.

I'm wondering if there are any sequencing issues or other considerations around this work as the solar will interact with the water heating? Should I just get the immersion replaced asap with a regular new tank and then let the solar set up integrate as and when I can get that to happen. Or is this an option to get anything special done tank wise if there's solar coming?

graememk

https://www.boards.ie/discussion/comment/122470798#Comment_122470798

Need to break the connection of Hot water and solar PV (I'm assuming your thinking about PV)

Currently its more cost effective to just export the excess solar and get paid for it than using an eddi to divert to hot water, via an immersion.

Continue heating water by traditional means. (what way do you heat your hot water?)

vixdname

10 X Bauer 445w panels , Split 6 rear and 4 frontal - 30 year warranty

Van der Valk Mounting Systems

4 X Huawei Smart PV Optimizers 

Huawei 5KW Inverter

€6825 after the SEAI grant.

Good / Bad ?

Emperor Tomato Ketchup

https://www.boards.ie/discussion/comment/122470928#Comment_122470928

The only heating in the house is solid fuel as it's very old and very remote. The stove is getting replaced tomorrow but back boiler stoves are more or less unavailable now (one guy offered me Henley back boiler stove but said they only last a decade at best). So electricity will be the only water heating going forward.

Emperor Tomato Ketchup

https://www.boards.ie/discussion/comment/122470928#Comment_122470928

Thanks for response, byw I don't really understand the term break here. But I am right that there is some issue over how they interact. And yes I was thinking of PV. Last time I looked at PV everyone seemed to be using ti to heat water but that was two years ago, maybe the feed in rates have improved enough to make that inefficient.

graememk

https://www.boards.ie/discussion/comment/122474061#Comment_122474061

Boiler stoves are still available : https://mybuildingsupplies.ie/shop/stoves-fires-fuel/solid-fuel-stoves/stanley-erin-stove

They last as long as most other heating sources, and really depends on how they are used. My Dad's one developed a leak in the boiler last year and there was no issue in getting replacement parts, (installed about 15 years, done all the heating in the house, It never cools in the winter). Most things inside a stove are classed as consumables. Pulled it out, replaced the boiler (basically the firebox) and rebuilt it.

The solar PV install (inverter, Panels) does not interact with the Hot water.

the heating of the water is done by its own device (eddi) and that just detects the solar export and can vary the power the immersion draws (by changing the voltage supplied to the immersion)

You are right in saying 2 years ago, diverters were the in thing as there was no Feed in Tariff.

If your removing the solid fuel boiler, what way are you planning on heating the rest of the house?

Recap:
PV generates electricity. Eddi just a fancy immersion controller. (approx €500)

If hot water tank is done, get a new well insulated one, Heat it on night rate, Export the solar excess.

askU

I'd like to know best case sanario for a roof top PV system...

What is the max power generation per hour in mid June on a sunny day (blue sky's from dawn to dusk) for a 10Kpw.

For

A) 90' South facing
B) 270' West facing

idc

https://www.boards.ie/discussion/comment/122477387#Comment_122477387

Use this tool with your homes location to calculate this, most people would look at first option "grid connected" which will give monthly energy output but there is also an "hourly" option if you need that much detail. Also realise if you have a 10kWp system and your inverter is only 5kW then your max AC output would be 5kW even on a perfect sunny day - if you have a battery that can change things as you could generate 5kW AC and at same time be charging battery with 5 kW

JRC Photovoltaic Geographical Information System (PVGIS) - European Commission (europa.eu)

askU

https://www.boards.ie/discussion/comment/122477495#Comment_122477495

Thanks but it doesn't give a very best case generation

graememk

https://www.boards.ie/discussion/comment/122478858#Comment_122478858

If on an nc6, with no battery.

5kW. Because that's the inverter limit.

With an oversized array, you may hit that limit in the morning and hold it to the afternoon.

*Technically you can go to 25amps, which is 5.5kW but there's no inverters in that middle ground, 6kW inverters are rated at 27.5 amps

My 8kWp, NE/SW array can easily hit 50kWh in a good day in may/June. (I have a 6kW inverter, installed before the rules changed

Why you asking that specific question?

askU

https://www.boards.ie/discussion/comment/122478902#Comment_122478902

I'm interested in actual efficiency.

askU

I'm not interested in the total in one day. I'm interested in the best case in ONE HOUR..in otherwords the best hour generated in the year.

Ok I'll rephrase.. ok so with a 5k inverter.
What is the highest power generated in the best hour in mid June on a sunny day (blue sky no clouds) for a 5Kpw system with 5k inverter.

A) 90' South facing
B) 270' West facing

graememk

https://www.boards.ie/discussion/comment/122480503#Comment_122480503

5kW.

graememk

https://www.boards.ie/discussion/comment/122480503#Comment_122480503

Although a bit more seriously this is a system a keep an eye on, on one of its best days.

About 8kW SW low slope, 6kW inverter

Not sure how much was lost to clipping, but the inverter was maxed out from about 11ish to about 4.

askU

@graememk

Thank you

So say if you had a 8k inverter.. you would achieved about 6.9kw..

Is your system on the ground or on roof?

graememk

https://www.boards.ie/discussion/comment/122480745#Comment_122480745

That one is on a roof, but it's very low slope (about 12degrees)

Id say if I had a 8kW inverter, it would have generated a peak of 8kW.

May and June are the best because it's cooler than July/August and the cooler panels are, the more power they can generate

Grumpypants

One final question before the lads land on tomorrow. I've a 6.8kw ( 16 x 430w panels) ground mount being installed so all south facing.

But only a 5kw Solis hybrid inverter.

I know over sizing a bit is a good idea. Solis says max input is 6.5kw. but I have room for one extra panel which would bring it up to 7.3kw. Is it still okay to go with that even though it's a good bit above the max, and assume that it will unlikely hit the max for long in cloudy Galway anyway?

graememk

I think it's much more?