Closed-Cycle Heat Recovery Engine for Waste Heat Power Generation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional power systems, such as steam plants and internal combustion engines, operate at low efficiency due to significant heat loss and waste heat, typically achieving only 30% efficiency, with most energy being rejected as heat to the environment.

Innovation Solution

A single-loop closed cycle thermodynamic system that uses a working fluid and a heat exchanger to transfer heat from a low-pressure power turbine to a high-pressure input, allowing for efficient conversion of heat to useful work without crossing the 'wet region' of the temperature versus entropy plot, achieving efficiencies into the 90% range.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If a conventional steam power cycle is used, then the system can generate power, but the efficiency is limited to 30% due to significant heat loss to the environment

Engineering Contradiction:

Improveheat lossVSAvoidpower generation efficiency

Core Design Contradiction:

Loss of energyVSProductivity

Solution Approach 1:

The patent converts the harmful waste heat that would normally be lost to the environment into a beneficial resource by using it to preheat the incoming working fluid through a heat exchanger. This transforms the 70% energy loss in conventional cycles into useful thermal energy, enabling the system to achieve over 90% efficiency by eliminating the need for separate heat rejection to the environment.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Ease of operation

If the return path crosses the wet region in the T vs. S plot, then the power cycle can be completed, but substantial heat loss occurs to the earth environment

Engineering Contradiction:

Improvecycle completionVSAvoidheat loss to environment

Core Design Contradiction:

Ease of operationVSLoss of energy

Solution Approach 1:

The patent inverts the conventional approach by having the working fluid return through the superheated region rather than the wet region. The heat exchanger enables the low-pressure exhaust to transfer its thermal energy to the high-pressure incoming fluid, allowing the cycle to complete its return path while maintaining the fluid in the superheated region and eliminating substantial heat loss to the environment.

Inventive Principle:

Principle #13The other way round (Inversion)

3Ease of operation

If gaseous compression is used in OTTO or diesel cycles, then the engine can operate, but much power is consumed during compression

Engineering Contradiction:

Improveengine operationVSAvoidpower consumption during compression

Core Design Contradiction:

Ease of operationVSUse of energy by moving object

Solution Approach 1:

The patent changes the physical state parameter of the working fluid from gaseous to liquid during compression. By pumping the fluid in liquid form through the liquid phase, the system avoids the high power consumption associated with compressing gases, as liquid pumping requires significantly less energy. This parameter change from gas to liquid state during the compression phase dramatically reduces the energy required for this critical process.

Inventive Principle:

Principle #35Parameter changes

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 system effectively captures ambient heat sources to generate power with minimal heat rejection, suitable for direct power extraction from geothermal wells, surface water, and air, and can be used as a bottoming cycle for existing power plants, achieving high efficiency and reducing environmental heat dumping.

Implementation Method 1

Use of heat-exchanger between low-pressure power turbine exiting heat, and incoming high-pressure input heat

Methodology Applied

Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 2

An expansion device downstream of the thermal input converts at least the heat of the working fluid to useful work

Methodology Applied

Scientific EffectThermodynamic expansion: Heat Engine

Implementation Method 3

The conversion device expands the working fluid with constant enthalpy from a higher to a lower pressure

Methodology Applied

Scientific EffectIsenthalpic expansion: Joule-Thomson Effect

Data Source

PatentUS10132201B2Ultra-high-efficiency closed-cycle thermodynamic engine system

Publication Date: 2018.11.20 BURKHART TECH

AI summary

A thermodynamic system and method for performing work includes a working fluid and a fluid pump for pumping the working fluid through a cycle. A thermal input supplies heat to the working fluid. An expansion device downstream of the thermal input converts at least the heat of the working fluid to useful work. A heat exchanger downstream of the expansion device has a first portion to transfer heat from downstream said expansion device to a second portion at or upstream of said thermal input. A conversion device expands the working fluid with constant enthalpy from a higher to a lower pressure.