Hydrostatically Compensated CAES Maintenance Method
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for an efficient and cost-effective method to store electrical energy produced during non-peak periods for later use, especially with the integration of renewable energy sources that are intermittent.
Innovation Solution
A hydrostatically compensated compressed air energy storage system is proposed, which includes an underground accumulator with a layer of compressed air above a layer of compensation liquid. The system uses an overcharge buffer apparatus to maintain the compressed air at a substantially constant pressure during charging and discharging modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If compressed air energy storage is implemented to store electrical energy during non-peak periods, then energy storage capacity is improved, but system complexity and infrastructure costs increase
Solution Approach 1:
The patent introduces a compensation liquid as an intermediary substance between the compressed air and the environment. This liquid layer acts as a mediator that transmits pressure changes while isolating the compressed air from direct contact with atmospheric pressure variations, thereby simplifying the overall system design by eliminating the need for complex pressure regulation mechanisms.
Solution Approach 2:
The patent employs a hydraulic principle by using a layer of compensation liquid to transmit and equalize pressure changes in the compressed air storage system. As air is compressed or expanded, the liquid layer moves vertically to compensate for volume changes, maintaining constant pressure through hydrostatic equilibrium, thus avoiding complex pneumatic control systems.
2Ease of manufacture
If traditional compressed air storage methods are used, then infrastructure costs are reduced, but pressure stability and energy efficiency deteriorate
Solution Approach 1:
The compensation liquid layer automatically adjusts its position in response to pressure changes in the compressed air, providing self-regulating pressure stability without requiring external control systems. The system serves itself by using the physical properties of the liquid to maintain constant pressure, eliminating the need for complex monitoring and adjustment infrastructure.
3Productivity
If the accumulator is designed to fully charge and discharge, then energy storage efficiency is improved, but maintenance accessibility and operational reliability worsen
Solution Approach 1:
The patent extracts the compensation liquid from the accumulator during maintenance operations, removing the liquid barrier to allow direct access to the air space and accumulator components. This temporary extraction enables technicians to perform maintenance tasks without dealing with the complex liquid-gas interface, thereby improving accessibility while maintaining full charging/discharging capability during normal operation.
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
The system effectively stores and releases electrical energy while maintaining the compressed air at a consistent pressure, enhancing the efficiency and reliability of energy storage and supply.
Implementation Method 1
A layer of compensation liquid may be positioned below the layer of compressed air in the accumulator and may be in communication with a source of compensation liquid
Implementation Method 2
A layer of compressed air may be positioned above the layer of compensation liquid in the accumulator
Data Source
AI summary
A method of transitioning a hydrostatically compensated compressed air energy storage system from an operating mode to a dewatered maintenance state may include a) charging an accumulator to a fully charged state where the air water interface is at a charge plane by conveying compressed air at a storage pressure into the layer of compressed air using a gas compressor/expander subsystem thereby displacing a corresponding amount of compensation liquid from the layer of compensation liquid out of the accumulator into the compensation liquid flow path and from the compensation liquid flow path into the compensation liquid reservoir until the accumulator is substantially free of the compensation liquid, b) fluidly sealing the compensation liquid flow path thereby isolating a residual amount of the compensation liquid, and c) depressurizing the accumulator interior to a service pressure that is lower than the storage pressure.