Preface to the special issues of the Fourteenth European Wave and Tidal Energy Conference (EWTEC 2021)

14th European Wave and Tidal Energy Conference (EWTEC 2021) was organized by the University of Plymouth, UK from 5th – 9th September 2021. It was the first time the conference had been hosted in the South West of the UK, and with the impact of COVID-19, it was also the first time the event was held in a full hybrid format with presenters and audience both in person and online.