At the risk of going way too far off topic here, if you take a look at the photos of the other villages they have provided solar equipment to, you'll see they use these to read/study/eat/hold meetings/even night-time work/etc. which they don't want to do during the heat of daytime, the pattern of light shed by a lantern is probably more conducive to these purposes. Why the shape of a lantern you ask?, probably a shape they are comfortable or familiar with.
Best regards,
Willis