Mae APB (Associated British Ports), Caerdydd, a Tata Shotton ar y rhestr fer o 18 safle posibl – wedi'u dewis o 121 mynegiant o ddiddordeb o ledled y DU.
ABP Port of Cardiff and TATA Shotton are among the list of just 18 potential sites, chosen from a total of 121 expressions of interest from across the UK.