[EvaH (OP)]

Paul suggests:

When they flew the solar plane around the world I wondered if they could have painted the plane in chlorophyll to assist in getting more energy - but I've read that solar panels are more efficient. Another idea I toyed with was coating the aircraft in green feathers where alternate barbs are connected and my theory would be as the aircraft passes through the air the air passing between the barbs builds up a potential difference which could be used.

What do you think?

[vhfpmr]

Whatever you use to harvest energy from the sun has to able to produce that energy in a form that can be utilised by the technology on the plane. In this case, that's electric motors, so unless someone has a means of using chlorophyll to produce electricity it won't be a lot of help. Presumably that's the case, or solar panels would be made of chlorophyll and not silicon.

You could argue that ordinary jet planes are powered by chlorophyll: plants use chlorophyll to produce hydrocarbons from water, air & sunlight, then hydrocarbons are used to produce jet fuel.

[alancalverd]

Anything you do that extracts energy from the airflow around a plane, slows the plane. If that were not the case, you could put a propeller on the front and a windmill at the back, and it would fly for ever!