Rod Nelson: "We have had no issues with the car today, so have made good progress."
Healthy teams should have priority over a rush to boost power outputs, according to veteran engineer.
Valtteri Bottas: "There are a lot of strengths in this car and we’ve made good progress in just one day, so I am very pleased."
The team showed strong development throughout last season and aim to continue this as the regulations show minimal changes for the new season ahead.
GP3 champion Alex Lynn has joined Williams as the team's development driver, in addition to his already announced GP2 programme with DAMS.
Nine weeks after the 2014 finale, Formula One is now counting down the mere days before the resumption of track action.
Williams is determined to continue this positive momentum into the new season.