The project has spent 10% of the total predicted expenditure, which is a condition of it getting the government 'contract for difference' support it was awarded in April 2014.
Burbo Bank was one of five offshore projects to be awarded a non-competitive contract last year. The contract guarantees a fixed price for the electricity produced over 15 years.
Milestone requirements include the turbine deal with MHI Vestas to supply 32 V164 8MW turbines, a foundation supply agreement with EEW, and the substation design contract with Atkins.
Onshore construction work in north Wales began in March at the site of the onshore substation. Offshore construction is due start in Q1 in 2016, according to a Dong spokesperson, with commissioning expected in 2017.
The site is located eight kilometers off the UK's west coast. It is next to the 90MW Burbo Bank project commissioned in 2007.