This is called The New Lighting (seriously), or HNB for short (for the Dutch name).
These tomatoes in Bleiswijk do not just get artificial light and sunlight from above, but also LED light from below. The lamps hang in amongst the plants, so that more light reaches the leaf surfaces and energy savings of 40 percent are possible. An experiment will start on 30 August to establish whether The New Lighting works on tomatoes due to be harvested around Christmas as well. Those tomatoes are experience because there is so little daylight.