Accurate investment returns data

jjnr78 · Sep 20, 2011

Hi all. I'm looking for some help with calculations. I'm new to Solar and am just starting the madness of putting together quotations.

I obviously understand the SAP calculation...straightforward stuff, but i've seen companies produce lovely looking investment returns (y1 to y25 etc) data based on individual projects. How and where do i start with this? I trialled PV Sol for a month, but unfortunately the job I was quoting for was a difficult install and the software didn't have the inverters that I was specifying. i simply ran out of time trying to get my head around the software and searching for others that might help me in producing accurate data in simple terms that 'Mr Smith' can understand and make informed decision on. My maths isn't the greatest and there are so many factors to consider. Did you present this data when you first started?

BruceB · Sep 20, 2011

REAL has some model documents which include how to put a feed in tariff illustration together
http://www.realassurance.org.uk/pdf/example-of-a-quotation.pdf
Regards
Bruce

Graeme Harrold · Sep 20, 2011

Presenting data can be frought with difficulties. A simple spreadsheet in excel can do this with compounding investment based on SAP and a best guess at inflation. The big companies seem to use higher rates to give dazzling ROI. Im producing info at 2-3% inflation thus giving a worst case representation on where the money will come from. My presented ROI's are roughly 9 years at 9%

jjnr78 · Sep 20, 2011

BruceB said:
REAL has some model documents which include how to put a feed in tariff illustration together
http://www.realassurance.org.uk/pdf/example-of-a-quotation.pdf
Regards
Bruce

Thanks Bruce. I remember seeing this now. I feel that I'm spending so much time trawling sites looking for info that I'm losing sight of the good starting points.

jjnr78 · Sep 20, 2011

If I'm being optimistic and expecting decent demand for my installs, is it worth the time and money investment to purchase PV Sol. Is there a better software?

The Solar King · Sep 20, 2011

There are other software packages available. If you can get your head around it there is Retscreen, which is free to download. I started to look at it for Solar thermal, gave up and purchased Tsol. Now involved in PV as well, so purchased PVsol. You could also look at Polysun.

PVsol Expert is quite a bit upfront. Taking the time to learn to use it properly or investing in the training will pay dividends. The shading calculation and 3D modelling is excellent. If you are using the trial version it will not have the latest database of equipment listed. Remember the climate data is also tied to somewhere in Germany in the trial version. It would have to be a pretty obscure inverter not to be listed in the full version. I have recently posted in another thread about the financial modelling it contains. If you can get to grips with all of its facilities it can produce a pretty accurate simulation of a given installation. In terms of customer presentation and equipment configuration I would not be without it.

Going on the training course really did help.

jjnr78 · Sep 21, 2011

Thanks Solar King...yeah price is a little lumpy but if it saves in time and produces accurate data then hopefully there will be a payback. out of interest how much is the training for expert?

The Solar King · Sep 21, 2011

£480.00 + VAT. I traveled to Wales for this, quite a Journey from Scotland but time constraints made this necessary. Training is also offered at other locations that may be more convenient to you. Details are on the Solar Design Company Web site.