Scottish energy minister Fergus Ewing is due to unveil investment at Scrabster Harbour, in Thurso Bay, Caithness.
Ewing said the port investment came on the back of the latest report from political think tank Reform Scotland, which suggested that Scotland could become the biggest exporter of low carbon electricity in Europe within a decade.
"Scotland’s energy will continue to be used across the UK and Europe in all future constitutional circumstances, including independence," said Ewing.
He added the funding will put the port "at the heart of the clean green energy revolution".