Volatiles effects on the thermal and chemical structures of H2 production in a hybrid porous media reactor using solar steam

•Gasification of carbonaceous feedstocks inside a porous media reactor.•Effect of volatiles on simulation of coal gasification with varying H2O/O2 ratios.•100% of solar energy used, with 20% thermal and 80% electric for the steam boiler.•Peak experimental temperatures between 1,200 K and 1,600 K.•H2/CO yields from coal gasification in the range of 0.6-1.2 where achieved.