SD Card - how to reduce the power consumption?

Using Arduino Storage
15

There is no limit on how many file you can have open. The only limit is RAM, each SdFile instance requires 31 bytes.

You must close an instance of SdFile before using it to open another file.

  SdFile file;

  file.open("config.csv", O_READ);
  // read data from config.csv
  file.close();
  file.open("log.csv", O_WRITE| O_CREAT | O_APPEND);
  // write to log.csv