DC/AC ratio

[Mohamed1298]

Could you please clarify what is the most recommend DC/AC ratio for utility scale plants? It's risky to increase the DC/AC ratio which makes the PR guarantee is not achievable with the irradiance increase in the future.

So, what is the min. And Max. Ratio to limit the risk of the PR in the OM years for utility scale projects?

[André Mermoud]

There is no "a priori" constraints. This completely depends on what you want to optimize, the available area, etc...

A "normal" DC:AC ratio, ensuring an oveload loss of, say, less than 1%, would be 1.25 to 1.3 (to be checked by the simulation).

Now for some PV plants, the  power injection to the grid may be limited by the grid manager. In this case it can be interesting to increase the PV array, in order to produce more energy, at the price of some additional overload loss, and therefore a diminution of the PR.

Now the PR is not necessarily the good parameter to be optimized. In many cases this may be the total produced energy, the final system profitability, etc...

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