Power generation system having thermal energy storage

Abstract

A power generation system includes a power generation module coupled to a thermal storage system via a heat transfer connection. The thermal storage system includes a heat storage medium contained in a storage tank. The thermal storage system is operable for receiving an energy input in the form of electrical energy or mechanical energy at a first point in time, converting the input energy into thermal energy, transferring the thermal energy to the heat storage medium to thereby cause an increase in enthalpy of the heat storage medium, and storing the thermal energy in the heat storage medium. The power generation module converts the stored thermal energy, which is recovered from the thermal storage system via the heat transfer connection, into an electrical power output. The stored thermal energy is recovered from the thermal storage system at a second point in time temporally shifted from the first point in time.

1 . A power generation system, comprising:
 a thermal storage system, comprising a heat storage medium contained in a storage tank, the thermal storage system being operable for receiving an energy input in the form of electrical energy or mechanical energy at a first point in time, converting the input energy into thermal energy, transferring the thermal energy to the heat storage medium to thereby cause an increase in enthalpy of the heat storage medium, and storing the thermal energy in said heat storage medium, and   a power generation module having a heat transfer connection with the thermal storage system, the power generation module being operable to convert the stored thermal energy, which is recovered from the thermal storage system via said heat transfer connection, into an electrical power output,   wherein the stored thermal energy is recovered from the thermal storage system at a second point in time temporally shifted from said first point in time.   
     
     
         2 . The power generation system according to  claim 1 , further comprising a renewable energy source, wherein the energy input to the thermal storage system in the form of electrical or mechanical energy is obtained from a power output of the renewable energy source. 
     
     
         3 . The power generation system according to  claim 1 , wherein the temporal shift is a function of a power demand from the power generation system. 
     
     
         4 . The power generation system according to  claim 2 , wherein the renewable energy source comprises a wind turbine. 
     
     
         5 . The power generation system according to  claim 2 , wherein the renewable energy source comprises a photo-voltaic cell. 
     
     
         6 . The power generation system according to  claim 3 , wherein
 in the first point in time, the power demand is lesser than a potential power output of the power generation system, and   in the second point in time, the power demand is greater than the potential power output of the power generation system.   
     
     
         7 . The power generation system according to  claim 2 , wherein the thermal storage system is part of a concentrated solar power (CSP) facility, and wherein the renewable energy source is located at the site of the CSP facility. 
     
     
         8 . The power generation system according to  claim 4 , wherein the energy input is obtained from a mechanical power output of the wind turbine, wherein the mechanical power output of the wind turbine is converted into thermal energy via a mechanical friction device, which has a heat transfer connection with the heat storage medium. 
     
     
         9 . The power generation system according to  claim 1 , wherein the energy input is in the form of electrical energy, wherein the thermal storage system further comprises an electrical heater element for converting the input electrical energy into thermal energy. 
     
     
         10 . The power generation system according to  claim 9 , wherein the electrical energy is obtained from the power output of a wind turbine or a photo-voltaic cell, wherein the power output of the wind turbine or the photo-voltaic cell is directly connected to the electrical heater element. 
     
     
         11 . The power generation system according to  claim 9 , wherein the electrical energy is obtained from a power grid, the power grid being supplied by at least one renewable energy source. 
     
     
         12 . The power generation system according to  claim 1 , wherein the power generation module includes a steam turbine power plant, comprising a steam generator or boiler that utilizes the thermal energy recovered from the thermal storage system to generate steam for driving a steam turbine. 
     
     
         13 . The power generation system according to  claim 1 , wherein the heat storage medium comprises phase-change material. 
     
     
         14 . The power generation system according to  claim 13 , wherein the phase-change material comprises a molten salt. 
     
     
         15 . A method for regulating a power output of a power generation system including a thermal storage system and a power generation module, the thermal storage system comprising a heat storage fluid contained in a storage tank, the method comprising:
 operating the thermal storage system for:
 receiving an energy input in the form of electrical energy or mechanical energy, 
 converting the input energy into thermal energy, 
 transferring the thermal energy to the heat storage medium to thereby cause an increase in enthalpy of the heat storage medium, and storing the thermal energy in said heat storage medium, 
 dispatching the stored thermal energy to the power generation module via a heat transfer connection between the power generation module and the thermal storage system, and 
   operating the power generation module for:
 converting the dispatched thermal energy into an electrical power output, 
   wherein the stored thermal energy is dispatched from thermal storage system at a second point in time temporally shifted from said first point in time.   
     
     
         16 . The method according to  claim 15 , wherein the energy input to the thermal storage system is in the form of electrical or mechanical energy is obtained from a power output of the renewable energy source. 
     
     
         17 . The method according to  claim 15 , wherein the temporal shift is a function of a power demand from the power generation system. 
     
     
         18 . The method according to  claim 17 , wherein
 in the first point in time, the power demand is lesser than a potential power output of the power generation system, and   in the second point in time, the power demand is greater than the potential power output of the power generation system.   
     
     
         19 . A method for retrofitting a power plant, comprising:
 coupling the power plant to a thermal storage system, the thermal storage system comprising a heat storage medium contained in a storage tank, the thermal storage system being operable for receiving an energy input in the form of electrical energy or mechanical energy at a first point in time, converting the input energy into thermal energy, transferring the thermal energy to the heat storage medium to thereby cause an increase in enthalpy of the heat storage medium, storing the thermal energy in said heat storage medium, and transferring the stored thermal energy from the thermal storage system to the power plant,   configuring the power plant to utilize the stored thermal energy transferred from the thermal storage system for electrical power production,   wherein the stored thermal energy is transferred from the thermal storage system for said electrical power production by the power plant at a second point in time temporally shifted from said first point in time.   
     
     
         20 . The method according to  claim 19 , wherein the thermal storage system is configured to receive the energy input in the form of electrical or mechanical energy from a power output of a renewable energy source.