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Table 4 Performance indicators

From: Impact of advanced electricity tariff structures on the optimal design, operation and profitability of a grid-connected PV system with energy storage

Indicator Description Formula
PV hosted capacity Ratio between the installed PV capacity and the potential PV capacity of the roof \(PV_{\text {host}} = \frac {\sum _{i=1}^{N} n^{\textsc {mod}}_{i} \cdot P^{\textsc {mod}}_{\text {nom},i}}{PV_{\text {potential}}}\)
energy curtailed ratio Fraction of the total PV production curtailed \(PV_{\text {curt}} = \frac {\sum _{t} P^{\textsc {cur}}_{t}}{\sum _{t} PV_{t}}\)
battery autonomy ratio Ratio between the installed battery capacity and the mean daily energy consumption \(\textsc {bat}_{\text {aut}} = \frac {\sum _{b=1}^{B} E^{\textsc {bat}}_{\textsc {cap},b}}{\text {mean daily energy}}\)
net present value The total net present value of the system (including battery replacement) \(\textsc {npv}=\frac {\sum _{t=1}^{L} \textsc {cf}_{t}}{\left (1+r\right)^{t}}\)
levelized cost of energy The NPV divided by the total consumed energy \(\textsc {lcoe} = \frac {\textsc {npv}}{L \cdot \sum _{t} P^{\textsc {load}}_{t}\cdot TS_{t}}\)
self-consumption Share of the PV production directly consumed by the system \(\textsc {sc} = \frac {\sum _{t\in T} \min (P_{t}^{\textsc {load}}+P_{t}^{\textsc {cha}},P_{t}^{\textsc {pv}})}{\sum _{t\in T} P_{t}^{\textsc {pv}}}\)
grid usage ratio Ratio between the maximum import, export power, and the maximum load power \(GU_{\textsc {imp,exp}} = \frac {\max P^{\textsc {imp,exp}}_{t}}{\max P^{\textsc {load}}_{t}}\)