Domestic solar PV quotes 2018

Scottie99 · 07-11-2018 08:47PM

I’ve noted through this thread that people are getting different sizes of systems, I’m not sure what size would suit my needs. I know an installer would survey then recommend, but I’d like to get info from other experienced folks on here.

We’ve a four bed detached house (Meath), roughly 1500sq. (4 persons)
Our annual electricity bill is roughly €1560 (€260 bimonthly)
We’ve a night meter, roughly 35/40% usage.
I’ve an EV doing 26/28K a year.

What size of system/battery others do you recommend?
What monthly/annual savings do you think the system could save me.
Obviously a rough cost after Government Grants.

Many thanks.

air · 07-11-2018 09:58PM

Scottie99 wrote: »

I’ve noted through this thread that people are getting different sizes of systems, I’m not sure what size would suit my needs. I know an installer would survey then recommend, but I’d like to get info from other experienced folks on here.

We’ve a four bed detached house (Meath), roughly 1500sq. (4 persons)
Our annual electricity bill is roughly €1560 (€260 bimonthly)
We’ve a night meter, roughly 35/40% usage.
I’ve an EV doing 26/28K a year.

What size of system/battery others do you recommend?
What monthly/annual savings do you think the system could save me.
Obviously a rough cost after Government Grants.

Many thanks.

Your daytime usage is pretty large, do you do a lot of EV charging during the day? A few energy saving initiatives would be the first port of call before you add PV.

wexfordman2 · 07-11-2018 10:17PM

H.E. Pennypacker wrote: »

They'll probably tell you the same thing that they told me - they can't discuss any details about contractors for data protection reasons and that the grant is only payable when the work is done by contractors that are on their approved list. I don't think that the last point is a big deal as once the contractor is tax compliant and uses properly qualified labour then there shouldn't be an issue getting on to the list.

Your array looks fantastic BTW

Just got word from the installers the seai checklist is out, so they should be scheduling my install soon, will be calling me tomorrow :-)

Shefwedfan · 07-11-2018 10:23PM

Scottie99 wrote: »

I’ve noted through this thread that people are getting different sizes of systems, I’m not sure what size would suit my needs. I know an installer would survey then recommend, but I’d like to get info from other experienced folks on here.

We’ve a four bed detached house (Meath), roughly 1500sq. (4 persons)
Our annual electricity bill is roughly €1560 (€260 bimonthly)
We’ve a night meter, roughly 35/40% usage.
I’ve an EV doing 26/28K a year.

What size of system/battery others do you recommend?
What monthly/annual savings do you think the system could save me.
Obviously a rough cost after Government Grants.

Many thanks.

Why the majority of the electricity on day rate?

b

uck51js9zml2yt · 07-11-2018 10:40PM

wexfordman2 wrote: »

Just got word from the installers the seai checklist is out, so they should be scheduling my install soon, will be calling me tomorrow :-)

That's good news. I should be hearing from him soon. Will be interested to see what he comes back with.

Scottie99 · 08-11-2018 06:49AM

Shefwedfan wrote: »

Why the majority of the electricity on day rate?

b

Actually, I’m wrong there. Instead of usage I put cost as a percentage - apologies

niallers1 · 08-11-2018 11:22AM

Hi Scottie99,
Your bi-monthly bill is at least twice what mine is for similiar family size. A bit off topic but have you looked at reducing your usage i.e not leaving appliances on standby oven, tv, microwave, radio, satelite box e.t.c. , turning off lights when not using a room, You should also change to LED lightbulbs. They use hardly any electricity and last years longer .
I went for a 4.2kw with 4.8kw battery. I have it in about 7 weeks now and think it's great. I don't expect to get much out of it in Nov/Dec/Jan but for the rest of the year it will cover most of my electricty needs.
in 7 weeks I've generated 362kwh ( October was 192kwh)

uck51js9zml2yt · 08-11-2018 06:40PM

My quote

14 x Solar PV Modules/Panels 325w
1 x 3.6kw Hybrid Inverters
3 x 2kw Hybrid Batteries
1 x Eddi
1 x Emergency Isolation
1 x BER Assessment
1 x Warranty

€11918
Less € 3800 grant.

Wexford ..how does it compare with yours?

Edit: I see you have an extra 4 panels and a bigger inverter for the same money !!
Quoted me an extra 1500(ex vat) for the bigger inverter and 4 extra panels.

unkel · 08-11-2018 07:53PM

Rip-off.

uck51js9zml2yt · 08-11-2018 08:39PM

unkel wrote: »

Rip-off.

Seems like it!!!

I was talking to a local man this evening. He's giving me a price.

unkel · 08-11-2018 08:50PM

You are aware that the installer has to be on the SEAI approved Solar PV installer list four you to get the subsidies though?

That said, there's a lot to say for doing a DIY install (or with your local man) and with an electrician hooking it up for you and forgetting about the subsidies...

Scottie99 · 08-11-2018 09:34PM

niallers1 wrote: »

Hi Scottie99,
Your bi-monthly bill is at least twice what mine is for similiar family size. A bit off topic but have you looked at reducing your usage i.e not leaving appliances on standby oven, tv, microwave, radio, satelite box e.t.c. , turning off lights when not using a room, You should also change out LED lightbulbs. They use hardly any electricity and last years longer .
I went for a 4kw with 4.8kw battery. I have it in about 7 weeks now and think it's great. I don't expect to get much out of it in Nov/Dec/Jan but for the rest of the year it will cover most of my electricty needs.
in 7 weeks I've generated 362kwh ( October was 192kwh)

I’m seeing the average running cost in Ireland for a 3/4 bed house is €224 bimonthly. I’m also running a car 4000km bimonthly, I think I’m doing ok.
The whole house has low energy bulbs, yes there are small saving to be made but I can’t see much.

http://www.moneyguideireland.com/much-average-electricity-bill.html

uck51js9zml2yt · 08-11-2018 09:42PM

unkel wrote: »

You are aware that the installer has to be on the SEAI approved Solar PV installer list four you to get the subsidies though?

That said, there's a lot to say for doing a DIY install (or with your local man) and with an electrician hooking it up for you and forgetting about the subsidies...

When I said local, it was an approved company whose owner happens to be located less than 5 minutes from my house.

unkel · 08-11-2018 10:14PM

Keep us updated tatranska!

uck51js9zml2yt · 08-11-2018 10:28PM

unkel wrote: »

Keep us updated tatranska!

I'll be talking to the others about the price difference between me and Wexford man.
They'd want some good excuse for the difference in price !

wexfordman2 · 08-11-2018 11:19PM

Brecken Tart Newscast wrote: »

I'll be talking to the others about the price difference between me and Wexford man.
They'd want some good excuse for the difference in price !

Is it the same supplier as mine?

uck51js9zml2yt · 08-11-2018 11:45PM

wexfordman2 wrote: »

Is it the same supplier as mine?

Yes. It's the company you told me about!

gunnerfitzy · 09-11-2018 11:13AM

Brecken Tart Newscast wrote: »

My quote

14 x Solar PV Modules/Panels 325w
1 x 3.6kw Hybrid Inverters
3 x 2kw Hybrid Batteries
1 x Eddi
1 x Emergency Isolation
1 x BER Assessment
1 x Warranty

€11918
Less € 3800 grant.

Wexford ..how does it compare with yours?

Edit: I see you have an extra 4 panels and a bigger inverter for the same money !!
Quoted me an extra 1500(ex vat) for the bigger inverter and 4 extra panels.

Is there not a difference in battery configurations? I think Wexfordman2 is getting 2 x 2.5kWh batteries. Only 1 kWh in the difference I know but still a different configuration and possibly manufacturer. Also, I think Wexfordman2 played hardball and squeezed a further reduction in the quote first mentioned.

wexfordman2 · 09-11-2018 11:46AM

gunnerfitzy wrote: »

Is there not a difference in battery configurations? I think Wexfordman2 is getting 2 x 2.5kWh batteries. Only 1 kWh in the difference I know but still a different configuration and possibly manufacturer. Also, I think Wexfordman2 played hardball and squeezed a further reduction in the quote first mentioned.

The inverter is smaller as well, mine is/will be a 5kw inverter. Double check it is the right size , itcould be a typing error.

unkel · 09-11-2018 11:58AM

It is plain stupid that tatranska got a quote for a battery system with 4.6kwp and just a 3.6kW hybrid inverter. Do these installers take us for fools or are they just completely incompetent?

What if your solar array produces maximum power and your battery is full and your house draws say 5kW? With the suggested setup you will use 3.6kW from the panels (that's all the inverter can give you), send 1kW to the grid for free and at the same time import and pay for 1.4kW from the grid :rolleyes:

With a 5kW hybrid inverter you send nothing for free to the grid and there is no need to import and pay for anything from the grid either...

KCross · 09-11-2018 01:14PM

unkel wrote: »

It is plain stupid that tatranska got a quote for a battery system with 4.6kwp and just a 3.6kW hybrid inverter. Do these installers take us for fools or are they just completely incompetent?

What if your solar array produces maximum power and your battery is full and your house draws say 5kW? With the suggested setup you will use 3.6kW from the panels (that's all the inverter can give you), send 1kW to the grid for free and at the same time import and pay for 1.4kW from the grid :rolleyes:

With a 5kW hybrid inverter you send nothing for free to the grid and there is no need to import and pay for anything from the grid either...

I dont think its that simple.
If you size the inverter too high you lose more when the production is low... is my understanding.

So, iirc, its better to size the inverter slightly less than the kWp to improve efficiency. Now, if you had medium term plans to add more panels it would make sense to get a larger inverter up front and just pay for install once.

conor_mc · 09-11-2018 01:24PM

Wexfordman2, would you mind pm’ing me your supplier please? Appreciate it!

unkel · 09-11-2018 01:30PM

KCross wrote: »

I dont think its that simple.
If you size the inverter too high you lose more when the production is low... is my understanding..

Nah. That's mostly from the past. Inverter are only marginally less efficient these
days anyway when not fully loaded

Hybrid inverters in a battery attached solar PV system need to be of higher power than the max of the solar array. It is plain ridiculous to be having to give electricity to the grid back for free while your battery is full and you have to buy electricity from the grid at the higher rate at the same time.

randombar · 11-11-2018 12:22AM

Hi All,

I've herself sold on this. I just need to sell it to myself a bit more.

It would be useful to know the price of the bee cert if people had it as some are quoting with and others without.

Is there somewhere you can calculate daily average return per month per panel or something.

Adding a battery in and calculating size v cost, working out what that will do for your demand. I.e. you charge it up during the day. Everyone gets home and uses it in the evening. Should you charge up again on night saver over night and use in morning?

I'm averaging 8.69 units per day and 2.92 units per night

Is the eddi worth it if you have solar thermal already (I doubt it)

A few quotes aren't including the essential load wiring. I'm guessing any electrician can do this. Is it a day's work? An idea of costs? Many additional parts required?

Thanks,
Gary

P.S. bargain alerts will have cost me a fraction of what this thread is going to ðŸ˜

air · 11-11-2018 08:51AM

unkel wrote: »

With the suggested setup you will use 3.6kW from the panels (that's all the inverter can give you), send 1kW to the grid for free and at the same time import and pay for 1.4kW from the grid :rolleyes:

Your assertion here that it is possible to simultaneously import and export to the grid just highlights that you have little to no understanding of the subject at hand.
It might be better to hold off on the advice until you pick up some basic knowledge and understanding of the area so you don't mislead other people further.

In the situation outlined, (5kw production, 5kW load, 3.6kW inverter) the PV will provide 3.6kW to the load via the inverter and the remainder of 1.4kW will be imported from the grid.

On the inverter sizing, it always has been and remains, good practice to undersize the inverter.

Every inverter has a minimum base load for operation and this is proportional to it's maximum output capacity. The bigger the inverter the lower the part load efficiency will be in general terms.
Granted it's normally undersized by slightly less than in this instance.
With a 5kW array the number of hours in the year
(in Ireland) that production will be between 3.6kW and 5kW is quite limited.
As a result the clipping of total energy production is not hugely significant. Furthermore any clipping is likely to occur in mid summer when production is likely to be exceeding both consumption and battery storage capacity. With zero FIT that missed portion is usually worthless.

With an array of 5kW it is even more likely than normal to be split over 2 strings facing different directions which only serves to reduce peak production further.
A multi directional array is generally desirable as it helps increase self consumption by extending the production day in a zero FIT environment such as currently exists.

Finally a 5kW inverter may well require a larger battery bank than a 3.6kW one depending on the charge and discharge capability of the battery selected if it is to be able to charge and discharge at 5kW.

The marginal cost of the bigger battery in addition to the uplift for the 3.6kW to 5kW inverter is likely to have a payback of many decades since there is no grant aid for this element.

antoinolachtnai · 11-11-2018 12:52PM

This is slightly off-topic but is it possible to get these hybrid inverters to discharge towards the grid, i.e., discharge even if there is little or no loadinside the home? How is that done? (This would be importanr if you eanted to use these units to balance the grid.)

KCross · 11-11-2018 01:57PM

air wrote: »

On the inverter sizing, it always has been and remains, good practice to undersize the inverter.

Every inverter has a minimum base load for operation and this is proportional to it's maximum output capacity. The bigger the inverter the lower the part load efficiency will be in general terms.

That was exactly what I understood too.

Do you have qualificatons yourself in the SolarPV area?

air wrote: »

Granted it's normally undersized by slightly less than in this instance.
With a 5kW array the number of hours in the year
(in Ireland) that production will be between 3.6kW and 5kW is quite limited.

Indeed. I think the bit unkel is missing is that you dont decide to put in 5kWp vs 4kWp to get 5kW from the panels. The extra panels in that case is to boost your overall generation at the lower end, not to try to achieve 5kW.

As you said, the lost/clipped 1kW is going to be rare, particularly if you have battery storage.

How often would you really have a battery full AND 5kW being generated AND then need 5kW of continuous load at that exact time. Thats going to be an insignificant amount of time. It would require something like an EV to suck up that level of power and the EV would need to be at home.

If it was possible to get a 5kW inverter at the same cost and same efficiency as a 3kW inverter then of course you would buy it but clearly thats not the case. There is a cost.

air wrote: »

With an array of 5kW it is even more likely than normal to be split over 2 strings facing different directions which only serves to reduce peak production further.
A multi directional array is generally desirable as it helps increase self consumption by extending the production day in a zero FIT environment such as currently exists.

This is exactly what I'm considering myself and what I asked for in my quotes.

I dont want all the panels south facing and then giving me little generation in the evening, so I'm planning to split it into two orientations so that I get a decent generation right up until sun down. An even smaller inverter is required in that case depending on how you split the panels.

KCross · 11-11-2018 02:19PM

GaryCocs wrote: »

Hi All,

I've herself sold on this. I just need to sell it to myself a bit more.

It would be useful to know the price of the bee cert if people had it as some are quoting with and others without.

Is there somewhere you can calculate daily average return per month per panel or something.

Adding a battery in and calculating size v cost, working out what that will do for your demand. I.e. you charge it up during the day. Everyone gets home and uses it in the evening. Should you charge up again on night saver over night and use in morning?

I'm averaging 8.69 units per day and 2.92 units per night

Is the eddi worth it if you have solar thermal already (I doubt it)

A few quotes aren't including the essential load wiring. I'm guessing any electrician can do this. Is it a day's work? An idea of costs? Many additional parts required?

Thanks,
Gary

P.S. bargain alerts will have cost me a fraction of what this thread is going to ðŸ˜

From analysis of my own consumption a battery makes no financial sense and I'm a high user of electicity.

The payback is, imo, 15yrs+
Thats just too long to be a sensible buy.

The quotes you get will talk about 7yr paybacks but they are generally rubbish claims as they use standard rate electricity for the calculations and they assume 100% utilisation of the energy by diverting to hot water which is skewing their figures to make it look better than it is.

The figure you should be using to calculate your payback should be the night rate of 8c/kWh unless the battery is displacing something that cant be moved to night rate (background load, cooking etc). And when calculating the day rate it should use the discounted rate that everyone can avail of which is around 17c/kWh right now, not the 20-22kWh that the SolarPV providers use in their calculations..... add it all up and the payback will be 15yrs+, not 7.... at least thats what fell out the bottom of my spreadsheet anyway.... YMMV.

By the time it has just paid for itself it will be very old tech, degraded and you are then crossing all your fingers that it will last another 10yrs to give you a payback. If anything goes wrong like a failed inverter (which does happen) your TCO is completely shot. It just doesnt make sense, imo. The payback needs to be <10yrs, preferably 5 to make it a sensible investment.

There is also the distinct possibility that there will be a Feed-in-tariff in the next 10yrs which will cost ALOT less than battery tech and is much more usable and scalable and you're not worrying about battery degradation etc. If you have stumped up for a battery and then a FiT comes in you will have wasted your investment, imo.

I know others on here believe in drawing the grant. I think its foolhardy. Decide for yourself but definitely run the numbers for your house and see what you get.

air · 11-11-2018 03:21PM

antoinolachtnai wrote: »

This is slightly off-topic but is it possible to get these hybrid inverters to discharge towards the grid, i.e., discharge even if there is little or no loadinside the home? How is that done? (This would be importanr if you eanted to use these units to balance the grid.)

It would just require a software change to trigger export when required and set up limits on charge and discharge levels. Discharging to the grid is no different to the home as far as the output stage of the inverter is concerned.

wexfordman2 · 11-11-2018 08:23PM

KCross wrote: »

From analysis of my own consumption a battery makes no financial sense and I'm a high user of electicity.

The payback is, imo, 15yrs+
Thats just too long to be a sensible buy.

The quotes you get will talk about 7yr paybacks but they are generally rubbish claims as they use standard rate electricity for the calculations and they assume 100% utilisation of the energy by diverting to hot water which is skewing their figures to make it look better than it is.

The figure you should be using to calculate your payback should be the night rate of 8c/kWh unless the battery is displacing something that cant be moved to night rate (background load, cooking etc). And when calculating the day rate it should use the discounted rate that everyone can avail of which is around 17c/kWh right now, not the 20-22kWh that the SolarPV providers use in their calculations..... add it all up and the payback will be 15yrs+, not 7.... at least thats what fell out the bottom of my spreadsheet anyway.... YMMV.

By the time it has just paid for itself it will be very old tech, degraded and you are then crossing all your fingers that it will last another 10yrs to give you a payback. If anything goes wrong like a failed inverter (which does happen) your TCO is completely shot. It just doesnt make sense, imo. The payback needs to be <10yrs, preferably 5 to make it a sensible investment.

There is also the distinct possibility that there will be a Feed-in-tariff in the next 10yrs which will cost ALOT less than battery tech and is much more usable and scalable and you're not worrying about battery degradation etc. If you have stumped up for a battery and then a FiT comes in you will have wasted your investment, imo.

I know others on here believe in drawing the grant. I think its foolhardy. Decide for yourself but definitely run the numbers for your house and see what you get.

The only thing is, the way the front works, is if you want a 4kwp system the grant requires the battery, so if the battery costs you 5k, the actual cost to you is 2,600 idlf you discount the additional 2,400 in grant money you will get.

Domestic solar PV quotes 2018

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