Complex sentence: In 2013, a solar system (established in 2012) was enlarged to supply water from the solar water pump and electricity to the makeshift boarding facilities, which by then accommodated up to 30 students, both boys and girls.
Split into simpler sentences: In 2013, a solar system (established in 2012) was enlarged to supply water from the solar water pump and electricity from the solar system to the makeshift boarding facilities. By then, the place they cover was accommodating up to 30 students, both boys and girls.