PV ROI Calculator Files


Apologies to Source forge for the 'Low Tech' solution, it seems out of place to me,
accessibility was a prime design choice.  
Irrespective, my other code will be high brow enough to make up for it.

============= System requirements: ==============

The  *.ods file were created with Libre Office as spreadsheets and anywhere that can run Libre Office ought be able to use them.


============== Purpose: ==============

The purposes of  PV_ROI_simple.ods are several

It allows someone skilled enough to use a spread sheet to compute a number that I call ROI.
As there are a number of depreciation models there are I believe more than one ROI.
This one is I believe rigorously defend-able as truth rather than merely acceptable to the tax office accounting practice.
That ROI is how much return you would have to make in order to be as well off after 15 years if you invested the cost of solar system elsewhere. The system is generously assumed to be worthless at that time. As the benefit of the solar system is assumed to be tax free, as per the tax office ruling for residential installs, the other return must be an after tax return to match the ROI computed.

It allows someone with yet more skill to modify or utilise the algorithms in the spreadsheet to better meet their personal needs.

It acts as resource for people with yet more skill to utilise the exposed computational methodology in their own projects. The code is GPL'd thus you cant save as it to an xls file and call it your work.
The math with the comments is in my view self explanatory and indeed relatively obvious. Thus almost any other level of rewriting is a novel implementation and not GPL'd.  

As goodish solar modelling is well exemplified elsewhere (eg PVWatts) this model uses a quick and dirty approach. Based on Melb having the magic number 3.6 kWHr/kW. The main novelty is its approach to ROI computation which simply computes results in today's dollars with what I think is least faffing around possible.

It also deliberately neither acquires nor utilises any more than the essential information to get ROI.
It could have worked out the entire bill before and after including the energy used at night. As that is not required and night usage just cancels out any it was removed. Real, (more user  friendly), UI's might (do) collect that information to give the user a fuller picture not just ROI. Their objectives are different not wrong.

GPL >v3.

Alan Chrsitiansen.

As always corrections welcome and acknowledged:

Acknowledgements:
		Your name goes here :)
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