Methods, Systems, and Devices for Quantifying Geothermal Heat Flux Using Vertical Temperature Profiles at Shallow Depths
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional deep borehole surveys for geothermal exploration are expensive, logistically challenging, and environmentally intrusive, limiting their frequency and spatial coverage, while shallow temperature measurements are compromised by surface temperature fluctuations, complicating the isolation of the geothermal heat signal.
Innovation Solution
A system using vertical profile temperature probes with fiber Bragg grating sensors, strain sensors, and natural advection sensors to measure temperature profiles at shallow depths, correcting for surface heating and fluid advection effects, and employing computational modeling to quantify geothermal heat flux.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If deep borehole surveys are used to measure geothermal heat flux, then measurement accuracy is improved by reducing surface temperature interference, but cost and logistical complexity increase substantially
Solution Approach 1:
The patent extracts the temperature measurement function from deep borehole environments and relocates it to shallow depths by using multiple sensors at different depths. This allows the system to measure geothermal heat flux without requiring deep boreholes, thereby reducing complexity while maintaining measurement capability through mathematical reconstruction of the temperature gradient.
Solution Approach 2:
The patent transitions from a single-point deep measurement approach to a multi-depth shallow measurement approach. By distributing sensors across multiple shallow depths and using temporal measurements, the system creates a dimensional shift that allows accurate geothermal heat flux calculation without the need for deep boreholes.
2Measurement precision
If deep borehole surveys are used to measure geothermal heat flux, then measurement accuracy is improved by reducing surface temperature interference, but spatial coverage and survey frequency decrease
Solution Approach 1:
The patent extracts the measurement function from deep boreholes and implements it at shallow depths using multiple sensors. This extraction allows surveys to be conducted more frequently and across greater spatial coverage since shallow boreholes are cheaper and logistically simpler, while the multi-sensor approach maintains measurement accuracy.
Solution Approach 2:
The patent uses relatively inexpensive shallow borehole temperature sensors that can be deployed frequently and at multiple locations. These shallow measurements, when combined through the described methodology, provide accurate geothermal heat flux data without the high cost and logistical burden of deep boreholes, enabling higher survey frequency and broader spatial coverage.
3Device complexity
If shallow depth temperature measurements are used, then cost and logistical complexity are reduced, but measurement accuracy deteriorates due to surface temperature fluctuations
Solution Approach 1:
The patent segments the temperature measurement function across multiple sensors at different shallow depths rather than using a single deep sensor. This segmentation allows the system to capture the temperature profile and use mathematical methods to isolate the geothermal signal from surface temperature fluctuations, maintaining accuracy while using shallow measurements.
Solution Approach 2:
The patent uses temporal feedback by taking repeated temperature measurements over time at multiple shallow depths. This time-series data allows the system to distinguish between transient surface temperature effects and the steady-state geothermal heat flux signal, thereby maintaining measurement accuracy despite using shallow sensors.
4Productivity
If shallow depth measurements are used, then cost is reduced and spatial sampling density increases, but the ability to isolate geothermal heat signal deteriorates
Solution Approach 1:
The patent segments the measurement system into multiple sensors at different shallow depths, allowing spatial sampling density to increase. The segmentation enables mathematical reconstruction of the temperature gradient that isolates the geothermal heat signal from surface effects, preventing information loss despite using shallow measurements.
Solution Approach 2:
The patent adds the temporal dimension to the measurement approach by collecting time-series data at multiple shallow depths. This dimensional change allows the system to filter out surface temperature variations and isolate the geothermal heat signal, maintaining signal isolation capability while achieving high spatial sampling density.
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
Enables reliable and cost-effective geothermal heat flux quantification at shallow depths, reducing costs and increasing spatial sampling density, while maintaining high measurement accuracy and adaptability to various geological and climatic conditions.
Implementation Method 1
A system using vertical profile temperature probes with fiber Bragg grating sensors
Implementation Method 2
correcting for surface heating and fluid advection effects
Implementation Method 3
correcting for surface heating and fluid advection effects
Data Source
AI summary
Methods, systems, and devices for quantifying geothermal heat flux using shallow subsurface temperature measurements are provided. A method can include deploying vertical temperature probes with fiber optic sensors, strain sensors, and advective sensors at measurement sites. Time-series temperature data is then recorded, processed to determine equilibrium temperature profiles, and corrected for climate-driven signals, strain, and advection effects. Geothermal heat flux is calculated by combining the corrected temperature gradient with subsurface thermal conductivity, and a heat flux map can be generated to identify geothermal energy resources.