The Bath Novel Award has been running since 2013 and is one of the most prestigious novel competitions for unpublished authors in the UK (along with a handful of others including the Bridport Prize).
Entries should include up to 5,000 words of your novel along with a one-page synopsis. The entry fee of £29 is on the high side when it comes to writing competitions. But then the judges and readers need to assess 5,000 words for each entry (rather than something like 300 for flash fiction entries), so it is understandable. And the top prize of £3,000 is also very nice indeed. There are also some sponsored entries for low income writers, details of which can be found HERE.