Thermal Energy Storage in Aquifers

Detailed overview of innovation with sample startups and prominent university research


What it is

Thermal energy storage (TES) in aquifers involves storing thermal energy, either heat or cold, in underground aquifers. Aquifers are layers of permeable rock or sediment that contain water. This technology offers a sustainable and efficient way to store energy for heating and cooling applications, utilizing the Earth’s natural thermal capacity.

Impact on climate action

Thermal Energy Storage in Aquifers under Thermal & Mechanical Storage elevates climate action by storing excess thermal energy underground. By utilizing aquifers as reservoirs, this innovation provides a sustainable solution for energy storage, reduces reliance on fossil fuels, and promotes the integration of renewable energy sources, mitigating carbon emissions.

Underlying
Technology

  • Aquifer Thermal Energy Storage (ATES): ATES systems typically involve a pair of wells drilled into an aquifer. During the summer, cold water is extracted from one well, used for cooling purposes, and then injected back into the aquifer through the other well, storing the heat underground. In the winter, the process is reversed, with warm water extracted for heating and cold water injected back into the aquifer.
  • Aquifer Characteristics: The suitability of an aquifer for TES depends on its geological characteristics, such as permeability, porosity, and water quality.
  • Heat Pumps: Heat pumps are often used in conjunction with ATES systems to extract or inject heat from the aquifer, improving efficiency and expanding the temperature range of the system.
  • System Design and Operation: ATES systems require careful design and operation to ensure efficient energy storage and retrieval, as well as to prevent contamination of the aquifer.

TRL : 6-7


Prominent Innovation themes

  • Advanced Aquifer Characterization Techniques: New technologies, such as geophysical surveys and tracer tests, are improving the understanding of aquifer characteristics and their suitability for TES.
  • High-Efficiency Heat Pumps: Advancements in heat pump technology are improving the efficiency and performance of ATES systems, reducing energy consumption and costs.
  • Smart Control Systems: AI-powered control systems can optimize the operation of ATES systems, predicting energy demand and supply, and managing the charging and discharging of thermal energy.
  • Hybrid ATES Systems: Hybrid systems that combine ATES with other energy storage technologies, such as solar thermal or geothermal energy, can offer greater flexibility and a wider range of applications.

Other Innovation Subthemes

  • Geological Characterization Optimization
  • Seasonal Energy Balancing
  • Next-Gen Heat Pump Integration
  • Aquifer Contamination Prevention
  • Predictive Energy Management
  • Deep Aquifer Utilization
  • Localized ATES Networks
  • Geothermal Synergy Optimization
  • Permeability Enhancement Techniques
  • Miniaturized ATES Systems
  • Real-Time Monitoring Solutions
  • Aquifer Retrofitting Strategies
  • Advanced Thermal Energy Modeling
  • Aquifer Capacity Expansion
  • Cold Energy Utilization

Sample Global Startups and Companies

  1. Enerdrape:
    • Technology Enhancement: Enerdrape specializes in thermal energy storage solutions using aquifers, leveraging the natural properties of underground water reservoirs to store and retrieve thermal energy. Their system involves circulating heat exchange fluids through boreholes in the ground, transferring heat to or from the aquifer for seasonal energy storage and retrieval. This innovative approach allows for efficient and sustainable utilization of renewable energy sources such as solar thermal and waste heat.
    • Uniqueness of the Startup: Enerdrape stands out for its expertise in utilizing aquifers for thermal energy storage, offering a cost-effective and scalable solution for long-term energy storage and demand management. By leveraging the large thermal capacity of aquifers, they provide a flexible and environmentally friendly alternative to conventional energy storage technologies.
    • End-User Segments Addressing: Enerdrape serves a diverse range of end-user segments, including residential, commercial, industrial, and district heating applications. Their thermal energy storage solutions are suitable for buildings, communities, and industrial facilities seeking to optimize energy efficiency, reduce carbon emissions, and integrate renewable energy sources into their heating and cooling systems.
  2. ICAX Limited:
    • Technology Enhancement: ICAX Limited specializes in ground-source heat pump systems and thermal energy storage solutions utilizing aquifers. Their patented technology, known as Interseasonal Heat Transfer, involves extracting heat from buildings during the summer months and storing it in aquifers for use in space heating during the winter. This innovative approach maximizes the efficiency of heat pump systems and enables year-round heating and cooling with minimal energy consumption.
    • Uniqueness of the Startup: ICAX Limited stands out for its pioneering work in interseasonal thermal energy storage, offering a holistic approach to sustainable heating and cooling using aquifers. Their integrated system design and control algorithms optimize energy performance and minimize environmental impact, making them a leader in the field of renewable energy-based heating and cooling solutions.
    • End-User Segments Addressing: ICAX Limited serves building owners, developers, and energy providers seeking efficient and sustainable heating and cooling solutions. Their interseasonal thermal energy storage systems are deployed in residential, commercial, and institutional buildings, as well as district heating networks, providing year-round comfort and energy savings.
  3. Geological Survey of Denmark and Greenland (GEUS):
    • Technology Enhancement: The Geological Survey of Denmark and Greenland (GEUS) conducts research and provides expertise in geoscience and environmental studies, including the characterization and modeling of aquifers for thermal energy storage. Their work involves mapping geological formations, assessing hydrogeological properties, and simulating heat transfer processes in aquifers to support the development of sustainable energy solutions.
    • Uniqueness of the Startup: GEUS stands out for its scientific expertise and research capabilities in aquifer thermal energy storage (ATES), offering valuable insights into the geological and hydrogeological factors influencing the feasibility and performance of thermal energy storage projects. Their research contributes to the advancement of ATES technology and the optimization of energy storage systems for various applications.
    • End-User Segments Addressing: While not a commercial startup, GEUS provides valuable information and support to government agencies, research institutions, and energy industry stakeholders involved in thermal energy storage projects. Their research findings and geological data help inform decision-making processes and promote the sustainable utilization of aquifers for energy storage and climate mitigation initiatives.

Sample Research At Top-Tier Universities

  1. Technical University of Delft (TU Delft):
    • Research Focus: TU Delft is at the forefront of research on Thermal Energy Storage in Aquifers, focusing on developing advanced techniques for storing and retrieving thermal energy in underground aquifer systems.
    • Uniqueness: Their research involves characterizing subsurface geology, hydrogeology, and thermohydraulic properties to identify suitable aquifer formations for thermal energy storage. They develop numerical models, simulation tools, and monitoring methods to assess system performance, optimize operation strategies, and mitigate potential risks associated with groundwater quality and well interference.
    • End-use Applications: The outcomes of their work have applications in district heating and cooling, renewable energy integration, and seasonal energy storage. By leveraging aquifer storage for thermal energy, TU Delft’s research contributes to reducing energy costs, minimizing environmental impacts, and enhancing the flexibility and reliability of energy systems.
  2. Stanford University:
    • Research Focus: Stanford University conducts pioneering research on Thermal Energy Storage in Aquifers, leveraging its expertise in subsurface engineering, geophysics, and sustainable energy systems to develop innovative solutions for underground thermal energy storage.
    • Uniqueness: Their research encompasses the design and optimization of injection and extraction wells, flow control mechanisms, and heat exchange processes to maximize thermal energy storage capacity and efficiency in aquifer reservoirs. They also investigate coupled processes, such as heat conduction, fluid flow, and geochemical reactions, to understand the long-term performance and environmental impact of aquifer storage systems.
    • End-use Applications: The outcomes of their work find applications in building energy management, industrial process heating, and renewable power generation. By harnessing aquifer storage for thermal energy, Stanford’s research enables load shifting, demand response, and energy arbitrage, contributing to grid stability, energy resilience, and carbon emissions reduction.
  3. KTH Royal Institute of Technology (Sweden):
    • Research Focus: KTH Royal Institute of Technology is engaged in innovative research on Thermal Energy Storage in Aquifers, leveraging its expertise in groundwater modeling, numerical simulation, and environmental engineering to develop sustainable solutions for energy storage and utilization.
    • Uniqueness: Their research involves investigating aquifer-aquifer and aquifer-surface water interactions, heat transfer mechanisms, and water quality impacts to optimize the design and operation of thermal energy storage systems. They also explore the integration of aquifer storage with renewable energy sources, such as solar and wind power, to enhance system efficiency and resilience.
    • End-use Applications: The outcomes of their work have applications in district-level energy planning, industrial process optimization, and agricultural heating. By utilizing aquifer storage for thermal energy, KTH’s research supports the transition to a low-carbon energy system, mitigating climate change impacts and fostering sustainable development.

commercial_img Commercial Implementation

ATES systems are being implemented in various commercial and institutional buildings around the world, particularly in Europe and North America. For example, the Drake Landing Solar Community in Alberta, Canada, utilizes a large-scale ATES system to store solar thermal energy for heating homes during the winter.