The Duke of Edinburgh was showing a black eye when he arrived with the Queen to open a new power plant near Port Talbot in south Wales.
Prince Philip, 83, had slipped in the bath and caught his eye with his thumb earlier this week.
The royal couple met workers and their families during their visit on Thursday.
The GE Energy power station at Baglan Bay has been described as one of the most advanced in the world.
A royal aide said earlier this week: "When people get older they tend to bruise more easily - he said it did not
The power station uses new technology to provide power 30% cheaper to industry in the surrounding Baglan Energy Park.
The Queen met people who work at the plant on her visit
US-owned GE Power Systems, which built the station, claims the station also burns gas more efficiently, causing less pollution.
Already several firms have been attracted to the park by the prospect of cheaper energy, including a paper company planning to create 340 jobs.
The power complex will feed into the national grid in Wales - as well as supplying energy to the energy park and BP's isopropanol plant nearby.
The construction of the park has provided employment for approximately 1,300 people.
As well as meeting workers, the Queen and the Duke of Edinburgh attended a lunch hosted by GE.
The Queen also unveiled a plaque made of Welsh slate to commemorate her visit.