Method for liquid air and gas energy storage
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Solution Overview
Problem
Current Liquid Air Energy Storage (LAES) systems integrated with Liquefied Natural Gas Storage and Re-gasification (LNGSR) terminals face inefficiencies in round-trip energy conversion, with round-trip efficiency below 65% and high energy losses, necessitating improvements in specific discharge power and thermal energy recovery.
Innovation Solution
The method involves interchanging waste thermal energy between re-gasified LNG and liquefied air, optimizing the mass flowrates of LNG and liquid air, and employing a closed-loop system for thermal energy recovery to enhance the efficiency of the LAES and LNGSR systems, including deep cooling and re-liquefaction processes to maintain a balanced energy flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If LAES systems are integrated with LNGSR terminals to enable thermal energy interchange, then round-trip efficiency increases significantly, but system complexity increases due to additional thermal recovery equipment and process integration requirements
Solution Approach 1:
The patent combines LAES and LNGSR systems into an integrated facility where waste thermal energy from LNG re-gasification is exchanged with process air streams. This merging of previously separate systems allows thermal energy recovery that dramatically improves round-trip efficiency while sharing common infrastructure such as compressors, heat exchangers, and storage tanks between the two processes.
Solution Approach 2:
The patent converts waste thermal energy from the LNG re-gasification process (which would otherwise be lost) into a useful resource for pre-heating process air and generating power during discharge mode. By utilizing this previously wasted thermal energy, the system achieves round-trip efficiencies exceeding 150%, turning a harmful energy loss into a beneficial contribution to system performance.
2Power
If mass flowrates of LNG and liquid air are optimized for thermal energy interchange, then specific discharge power increases, but energy losses increase during deep cooling and re-liquefaction processes
Solution Approach 1:
The patent optimizes the mass flowrate ratio of LNG to liquid air to maintain values between 0.9 and 1.1, which maximizes thermal energy interchange efficiency. By dynamically adjusting operating parameters such as compression ratios, temperatures, and flow rates, the system achieves high specific discharge power while minimizing energy losses during deep cooling and re-liquefaction through precise parameter control.
Solution Approach 2:
The patent implements continuous operation of the integrated LAES-LNGSR facility where LNG is continuously re-gasified and process air is continuously liquefied. This continuous operation allows thermal energy to be constantly transferred from the LNG stream to the air stream, eliminating idle periods and ensuring that the deep cooling and re-liquefaction processes operate at optimal efficiency continuously, thereby reducing specific energy losses.
3Loss of energy
If waste thermal energy is recovered through closed-loop interchange between LNG and process air, then energy losses reduce significantly, but device complexity increases due to additional heat exchangers and thermal management equipment
Solution Approach 1:
The patent designs heat exchangers and thermal management equipment that serve multiple functions within the integrated system. For example, the same heat exchangers used for thermal energy interchange also perform cooling duties for compressors and condensation for process air. This multi-functionality reduces the total number of separate equipment items needed, thereby limiting the increase in device complexity while still achieving significant energy loss reduction through closed-loop thermal recovery.
4Loss of energy
If deep cooling and re-liquefaction processes are employed to maintain balanced energy flow, then round-trip efficiency increases above 150%, but loss of substance increases due to refrigerant consumption and material handling
Solution Approach 1:
The patent implements a self-service thermal management system where the cold energy required for deep cooling and re-liquefaction is generated internally by the system itself. The expansion of liquid air in the turbine produces cold energy that is used to cool LNG during re-liquefaction, and the cold energy from LNG evaporation is used to cool process air. This internal cold energy recycling eliminates the need for external refrigerants and minimizes substance loss, while achieving round-trip efficiencies exceeding 150%.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly increases the round-trip efficiency of the Liquid Air and Gas Energy Storage (LAGES) facility, reduces energy losses, and enhances specific discharge power, achieving efficiencies above 150% and allowing for co-production of re-gasified NG and peaking power.
Implementation Method 1
interchanging a waste thermal energy between the LNG being re-gasified and a process air being continuously liquefied
Implementation Method 2
interchanging a waste thermal energy between the LNG being re-gasified and a process air being continuously liquefied
Implementation Method 3
liquefying a process air in the processes of its deep aftercooling
Implementation Method 4
continuous re-gasifying the LNG at said LAES facility
Data Source
AI summary
A method for liquid air and gas energy storage (LAGES) which integrates the processes of liquid air energy storage (LAES) and regasification of liquefied natural gas (LNG) at the import terminal through the exchange of thermal energy between the streams of air and natural gas (NG) in their gaseous and liquid states and includes harnessing the LNG as an intermediate heat carrier between the air streams being regasified and liquefied, recovering a compression heat from air liquefier for LNG regasification and utilizing a cold thermal energy of liquid air being regasified for reliquefaction of a part of send-out NG stream with its return to LNG terminal.