PROJECT ECONOMICS
A payback figure is only as useful as the assumptions underneath it. Commercial solar models should make those assumptions visible.
The main value streams
Solar can reduce imported electricity where generation overlaps with site demand. Electricity exported from the site may also have value, but the export rate and eligibility depend on the chosen arrangement.
Inputs that move the answer
Project cost, annual generation, self-consumption, import tariff, export value, degradation, operating costs and finance terms can all change the commercial result. A transparent model should separate measured site data from assumptions and should make sensitivity testing possible.
Avoid generic guaranteed payback claims
Two buildings with the same roof area can have different consumption profiles and therefore different self-consumption. Site-specific modelling is more useful than a generic headline payback period.
Related: Commercial solar · Project economics & finance
FROM GUIDE TO PROJECT
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