Patent ID: 8820080

Claim:
A method for cogeneration of electricity and useful heat using biomass comprising the steps of: combusting the biomass to produce heat, wherein said biomass does not require processing; heating a heat transfer fluid using said heat from said combusting step; carrying out an organic Rankine Cycle by: (i) pressurizing a liquid organic refrigerant; (ii) vaporizing said organic refrigerant using heat from said heat transfer fluid; (iii) harnessing mechanical power from said organic refrigerant using a positive displacement mechanical device; and (iv) condensing said organic refrigerant to a liquid state thereby liberating heat; (v) transferring at least a portion of said mechanical power to a generator; (vi) generating electricity using said generator; and (vii) capturing as useful heat, said useful heat comprising at least a portion of said heat liberated in said condensing substep of said organic Rankine Cycle; and wherein said combusting step and said heating step are carried out in a combustion unit, the combustion unit comprising: a water jacket surrounding a burn box and in thermal communication with the heat transfer fluid; biomass grates configured to support the biomass; and augers comprising ash trays configured to remove ash from the combustion unit; and wherein the biomass grates and augers are in thermal communication with the water jacket.