An apparatus of power generation using solid oxide fuel cells (SOFC), comprising: an integrated thermal device, comprising: a burner forming an innermost layer; an igniter, said igniter activating said burner; a reformer, said reformer coating said burner at outside to form a second layer; an air preheater, said air preheater coating said reformer at outside to form a third layer, wherein the air preheater is configured to pass fresh air which absorbs heat of a high-temperature exhaust gas from the burner and heat of high-temperature air from cathode outlet; and a hot air outlet unit, said hot air outlet unit coating said air preheater at outside to form an outermost layer; a distributing unit, said distributing unit being fluidly connected with said reformer, said air preheater and said hot air outlet unit; a solid oxide fuel cell (SOFC) stack, said SOFC stack being connected with said distributing unit; and a heat exchanger, said heat exchanger being connected to the exhaust gas output of said burner; characterized in that the apparatus of power generation using solid oxide fuel cells (SOFC) further comprises: a holding furnace, said holding furnace coating said integrated thermal device, said distributing unit and said SOFC stack, wherein the heat exchanger is disposed outside said holding furnace. an integrated thermal device, comprising: a burner forming an innermost layer; an igniter, said igniter activating said burner; a reformer, said reformer coating said burner at outside to form a second layer; an air preheater, said air preheater coating said reformer at outside to form a third layer, wherein the air preheater is configured to pass fresh air which absorbs heat of a high-temperature exhaust gas from the burner and heat of high-temperature air from cathode outlet; and a hot air outlet unit, said hot air outlet unit coating said air preheater at outside to form an outermost layer; a burner forming an innermost layer; an igniter, said igniter activating said burner; a reformer, said reformer coating said burner at outside to form a second layer; an air preheater, said air preheater coating said reformer at outside to form a third layer, wherein the air preheater is configured to pass fresh air which absorbs heat of a high-temperature exhaust gas from the burner and heat of high-temperature air from cathode outlet; and a hot air outlet unit, said hot air outlet unit coating said air preheater at outside to form an outermost layer; a distributing unit, said distributing unit being fluidly connected with said reformer, said air preheater and said hot air outlet unit; a solid oxide fuel cell (SOFC) stack, said SOFC stack being connected with said distributing unit; and a heat exchanger, said heat exchanger being connected to the exhaust gas output of said burner; characterized in that the apparatus of power generation using solid oxide fuel cells (SOFC) further comprises: a holding furnace, said holding furnace coating said integrated thermal device, said distributing unit and said SOFC stack, wherein the heat exchanger is disposed outside said holding furnace. a holding furnace, said holding furnace coating said integrated thermal device, said distributing unit and said SOFC stack, wherein the heat exchanger is disposed outside said holding furnace.