FIRST INVESTMENT CALCULATION

[oum96-mah]

I have a bit of a problem with the first investment calculation. I'm trying to recalculate it and compare it to the value given in the Excel result file, but they're not the same. Is it possible to clarify the precise formula with which you calculate?

[smartie2076]

Hello @oum96-mah! The formula to calculate the present value of one investment unit is coded here:

offgridders/src/D1_economic_functions.py

Line 101 in 9095014

def capex_from_investment(investment_t0, lifetime, project_life, wacc, tax):

It takes into account the discount factor, asset lifetime, project lifetime, number of necessary replacements and the residual value at project end.

[smartie2076]

The description here is maybe easier to read, but it seems it is marked for updates: https://offgridders.readthedocs.io/en/latest/Cost.html?highlight=replacement#including-costs-in-oemof-optimization

(The funtion above is the way that it is actually implemented)