A rankine cycle system , comprising: a heater configured to circulate a working fluid comprising carbon dioxide in heat exchange relationship with a hot fluid to vaporize the working fluid; a hot system coupled to the heater ; wherein the hot system comprises a first expander configured to expand a first vaporized stream of the working fluid from the heater , a first heat exchanger configured to circulate said first vaporized stream of the working fluid from the heater in heat exchange relationship with a first condensed stream of the working fluid to heat the first condensed stream of the working fluid, a first condensing unit configured to condense the expanded first vaporized stream of the working fluid fed from the heater via the first heat exchanger and a first pump configured to feed the first condensed stream of the working fluid via the first heat exchanger to produce a second vaporized stream of the working fluid; and a cold system coupled to the heater and the hot system ; wherein the cold system comprises a second expander configured to expand the second vaporized stream of the working fluid from the first heat exchanger , a second heat exchanger configured to circulate the second vaporized stream of the working fluid from the hot system in heat exchange relationship with a second condensed stream of the working fluid to heat the second condensed stream of the working fluid, a second condensing unit configured to condense the expanded second vaporized stream of the working fluid fed from the second expander via the second heat exchanger and a second pump configured to feed the second condensed stream of the working fluid via the second heat exchanger to the heater . a heater configured to circulate a working fluid comprising carbon dioxide in heat exchange relationship with a hot fluid to vaporize the working fluid; a hot system coupled to the heater ; wherein the hot system comprises a first expander configured to expand a first vaporized stream of the working fluid from the heater , a first heat exchanger configured to circulate said first vaporized stream of the working fluid from the heater in heat exchange relationship with a first condensed stream of the working fluid to heat the first condensed stream of the working fluid, a first condensing unit configured to condense the expanded first vaporized stream of the working fluid fed from the heater via the first heat exchanger and a first pump configured to feed the first condensed stream of the working fluid via the first heat exchanger to produce a second vaporized stream of the working fluid; and a cold system coupled to the heater and the hot system ; wherein the cold system comprises a second expander configured to expand the second vaporized stream of the working fluid from the first heat exchanger , a second heat exchanger configured to circulate the second vaporized stream of the working fluid from the hot system in heat exchange relationship with a second condensed stream of the working fluid to heat the second condensed stream of the working fluid, a second condensing unit configured to condense the expanded second vaporized stream of the working fluid fed from the second expander via the second heat exchanger and a second pump configured to feed the second condensed stream of the working fluid via the second heat exchanger to the heater . <EOS>