Solar Panel Guide Discussion

Martyn1981

Hiya maravesi, certainly sounds like you do get it, but give it a few more sleeps to start to settle in.

Right, just some late night ponderings, nothing important.

Roof pitches - I'm only sticking a random pin in the BS10 area, but 38d gave me (per kWp) 991 for SSE and 528 for NNW, so 53% relative. Ouch!

Also, if you can get into the loft and have a clever phone or pad/tablet, you can download a free spirit level app, then hold it to the rafter.

Shading - that chimney is a pain, I think you'd have to go for a SE system. As you say, the soil pipe is to the lower northern tip, so not too bad. Would be simple and cheap (£20?) to shorten and fit an AAV. Have a look at it in the morning, we are 5 weeks from max sun, when it will rise furthest to the NE. If it's not much of an issue now, probably ok, but SE system, plus shortening will solve most of the issue.

Rear roof - brain hurting here, but lets say you manage to fit 12 panels on the other 2 rooves. So 4 (1kWp) on the N roof. Probably will add £1k (4 panels, rails and fixings, 4 power optimisers, extra scaffolding, and a bit of labour). 1kWp for £1k isn't bad, but at 53% performance of S roof, it's more like £2k/kWp ..... not good.

That £1k would give you an extra £80/panel to spend on the S & E rooves to improve performance through higher efficiency panels, or just £1k in the bank.

I think the big question is what'll fit on the side roof, it looks to be nearer 8m long? So working in 1.6m (landscape) lengths, you need to work out how many will go across, before the 1m height hits the ridge tiles. You may be able to do some measuring from the inside. The floor joists will probably meet the rafters (roof joists) roughly a tile up from the gutter - this is a good thing, as you'd need to leave approx 200mm at the bottom free anyway.

Next, start in the middle, measure 2.5m (for 3 panels, 5m) across, then 1m up and see if that fits. Try to keep going and see if you can fit 3, then 2, then 1 panel. Also play with a 0.8m rise, to see how the Panasonics might squeeze in.

I don't think the N roof is a dead duck yet, but I suspect it's got a bad limp, at best!

Mart.

EricMears

Martyn1981 wrote: »

Also, if you can get into the loft and have a clever phone or pad/tablet, you can download a free spirit level app, then hold it to the rafter.

It's even easier if you have a 'real' spirit level ! Failing that, hanging a weight on a piece of string from a nail banged into a rafter will give you a true vertical. In either case a protractor from a schoolkid's geometry set (we've probably all got one of them in our attic but if not just hang around outside a school gate ) will let you calculate the exact angle.

maravesi

Hi all


I had a play around quickly. Side roof is about 31d pitch and a triangle with sides of 6m and hypotenuse of about 8m (side of house is 7.7). We can fit 6 regular panels. I've just had the following quote which seems more resonable than what we've had before although given our low usage we couldn't achieve the savings that they've calculated:



"If you were to use the front roof only, you would probably have space for six panels – using a panel such as the LG305W would give you a 1.83kW system.It would cost about £4000 (including scaffolding and VAT) to supply and install, and would generate about 1740kWh (units of electricity) a year.
You would benefit from Feed In Tariff income of £275 a year, and annual bill savings of about £120.
That equates to a payback of 10 years (or a return on investment of 10%).
If you were also to install six panels on your side roof (ENE facing), then you would have a 3.66kW system, which would cost around £6000 (including scaffolding and VAT) to supply and install.
This system would generate about 2980kWh a year, producing annual Feed In Tariff income of £470 and bill savings of about £190.
That equates to a payback of 9 years, or a return on investment of 11%.
I hope that makes sense – if either option is of interest, we would be very happy to carry out a site survey and provide a firm quotation (free and without obligation), just let me know."


What do you think? I tried to calculate the £/W of panasonics 285 and benq 330s against the LGs and the LGs seem to work out best even if we try to squeeze 8 panasonics on the front as we'd still need 5 on the side. I don't know what inverter she has in mind for this quote, I assume not SE.

oldskoo1

Pleased to add my new solar install had its first day today.

I went from this



To this


It cost £4,750 to get to that point and i wish to have the weather from the first pic.

System is
16x 250watt onyx black PhonoSolar panels.
4000TL-D Samil solarRiver inverter

I am treating this primarily as an investment so i have done the numbers front, sideways and backwards. I have also assumed below expected generation and factored in the possibility of a slightly higher failure rate with the chinese equipment. I think its unfair to assume this as i have read german / european equipment failing just as much.

But i've factored everything in and i encourage anyone to get several quotes, be patient, do the numbers and under estimate generation (after making sure all desktop quotes show similar 20 year generation calculations).

I made a judgement call and in no particular order the factors to go with the Chinese kit and the installer we in no order, installer came recommended, price was great, kit was more towards the top end of chinese and has similar abilities and reliability to more "respected" kit.


The first day i had all weather, rain, dark cloud, light cloud, broken cloud, sunny spells, thunder and hail.

We did 16.48kWh is around 2kWh above the average for my location, time of year and install specifications : http://photovoltaic-software.com/pvgis.php

I also recommend using PVOutput and look for nearby solar arrays configured as similar as possible and of course with live output data. Then you can compare your generation with local arrays to see how you are doing. The closer the better as weather as i found out today is a big factor!

If you are wondering about my roof position, i left space for a 3rd row to make this a 6kW array if i felt i needed to in the future. My house is S facing, actually SSW by about 15degrees. Mounting the solar panels high up maximises the late evening sun cover.


Overall off to a very good start

oldskoo1

Hi all

I submitted my fit application and they called me for my opening reading.

I'm now not sure of the next steps. They emailed me I will receive a fit schedule within the next 42 days? Not sure what this is, seems a long time but I will be paid from he meter reading date.

Any ideas what this wait is for and if I need to do anything else.

Thanks

organum

Some of the information is confusing.
Like you I understood fit starts with the first requested meter reading.
Like you I heard nothing from in my case First Utility so I phoned. " You are on fit from the date of application as I sent in, as instructed, a photograph of the meter."
I now have this confirmed by email.

pinnks

FiT is paid each quarter from the date your application and opening meter reading is received. So, if you submit everything on the installation day it is paid on that date 3 months later and then every 3 months after that. If you delay submitting the forms the production to the date you submit the forms does not get any FiT.

Once the forms are processed they will send you confirmation and your schedule. That can take a few weeks but it does not matter as the payments are based on that meter reading you send in as the opening number and whatever is generated after that.

At the end of each quarter you have to provide a meter reading and have a window of a couple of weeks to do so. I am with EOn and can enter the readings online but you might have to send the reading by email. A week or two after the reading is submitted you should have the money in your bank.

oldskoo1

Noticed my consumer unit in the house buzzing today.

Went out to the meter box and the mcb in the mini consumer unit (my solar array and car charging point is on its own mini consumer unit in the meter box which then feeds into a combining box before it goes into the house and the main consumer unit) was also buzzing.

The iboost buzzes by the hot water tank too and my iMac has started buzzing since solar was installed.

Whilst I was at the mcb for the solar array I removed the batteries in the iboost sender unit assuming this was disable the iboost remotely (I hear iboost can cause buzzing) I'm not sure if the iboost turned off.

Made me think it was the AC feed into mcb causing buzzing on the entire circuit. Is this possible and can it be fixed?

ChopperST

I had the same when my immersun was installed and called the installer back - there was a loose connection somewhere causing the buzzing which was fixed and the problem never returned. I'm sorry I can't recall what the exact problem was.

Upwind

Just starting to investigate Solar panels in Nottinghamshire.

Anyone recommend any companies to me in east Notts area?

Would welcome any help or advice...