He worked through the day by sunlight, and into the night by candlelight.
VOA: special.2011.06.04
The basic idea, as is done here, of using sunlightthrough solar PV to electrolyse water, store the hydrogen then, when the power is required, reverse the process.
Slow down and look around: when rays of sunlightthrough the palm-frond roof illuminate a lute maker at work, you have found the Instrument-makers' Souq (Souq Kimakhine), and if you glimpse sparks flying as old bicycle parts are re-fashioned into lanterns, Blacksmiths' Souq (Souq Haddadine) has found you.