Noel Thomas, from Anglesey, was jailed for nine months in 2006 when his books fell short by £48,000.
Noel Thomas was wrongly convicted of false accounting but successfully appealed against conviction.
Noel Thomas is recognised for his campaigning, with Sir Alan Bates to be honoured on Thursday.
Noel Thomas was disqualified as a councillor when he was imprisoned in the Post Office IT scandal.
Tomos Wilson was caught on camera subjecting Ebehitale Igene to a torrent of vile abuse.
More than 700 people received criminal convictions because of a faulty computer system.
Two former postmasters remain angry and bitter over their treatment in a computer errors scandal.
Welsh firms are using seaweed and other materials to make compostable alternatives to plastics.
Noel Thomas is one of dozens to have their false accounting convictions quashed.
