Green phalaenopsis
 

I have just bought a Noid green Phalaenopsis. How are the green Phalaenopsis developed?

That looks like a standard white one to me. Some green coloration may show through from the chloroplasts in the outer layers of the bud before it expands. I'd bet that in time, those flowers will lose most of that.

if yours is a "green", then it probably arose as a spontaneous genetic variation in a seedling population. To maintain the colouring, it was then mericloned for mass production. ( hybrid seedling populations hardly/if ever, breed true to parent )

See this one - it seems very close to yours - in appearance

Phal. Norman's Jade 'Green Apple' (Phal. Prospector's Dream x Phal. Norman's Mist ' Montclair' AM/AOS)

The photo above could just be a color difference in the camera and computer monitors. I have a little yellow green phal, with a throat that is a bright "danger" yellow. It clearly looks green, then later fades more to yellow.