Human civilization is currently evolving at an unprecedented rate, with new breakthroughs every single day. This has become possible due to never-tapped-before levels of energy resources. However, the unsustainable development has recently raised concerns about adverse effects on the environment, resulting in a growing urgency to address issues pertaining to energy efficiency and climate change, especially in urban environments. Notably, rapid urbanization has worsened the urban heat island effect, a phenomenon where a city experiences significantly warmer temperatures than the surrounding rural areas, increasing the energy demand for heating and cooling systems. As a result, conventional air source heat pumps often suffer from reduced efficiency in high-temperature urban environments, prompting higher electricity consumption and operating costs. This pressing issue underscores the need for innovative, sustainable energy solutions.
The integration of ground source heat pump (GSHP) systems with energy piles has emerged as a promising answer to this challenge. Energy piles uniquely combine the structural support of foundation systems with geothermal heat exchange capabilities, providing a dual-purpose solution that aligns with smart city development goals. In addition, advances in geotechnical and energy technologies have made it possible to implement these systems in diverse urban conditions.
In a recent study, a team of researchers, led by Professor Shinya Inazumi from the College of Engineering at the Shibaura Institute of Technology and Associate Professor Apiniti Jotisankasa from Kasetsart University, has comprehensively reviewed the integration of GSHP systems with energy piles. Their paper was published in Smart Cities on November 25, 2024.
Prof. Inazumi remarks, "In recent years, there has been an increasing global emphasis on reducing carbon emissions and transitioning to renewable energy sources. This study aimed to provide a practical, scalable solution that bridges geotechnical engineering with renewable energy systems, contributing to sustainable urban infrastructure while addressing critical issues of energy management and environmental impact."
The combination of GHSP systems and energy piles is a transformative approach to reducing electricity consumption and operating costs in cities facing growing energy demands. It takes advantage of stable ground temperatures to provide efficient heating and cooling, thus outperforming traditional air-source systems. Furthermore, it promotes heat dissipation through optimized groundwater circulation, ensuring the longevity and performance of geothermal systems.
In the review, the researchers emphasize the need for tailored design and adaptive management of the proposed dual-structure infrastructure and advocate site-specific strategies to maximize benefits. In residential, commercial, and industrial buildings, these systems can significantly reduce heating and cooling costs while reducing carbon emissions. Smart cities can incorporate energy stacks into infrastructure replanning, aligning with climate action goals and improving resilience to the urban heat island effect. Notably, energy piles can be embedded in roads, bridges, and underground transportation systems to manage thermal loads. This integration could optimize the energy efficiency of transportation facilities and extend their structural life. Furthermore, these systems can complement solar and wind energy by providing stable thermal energy storage, improving the overall efficiency of the current energy system.
"Government-backed subsidies or tax rebates could encourage the widespread adoption of this technology, further reducing barriers such as high initial installation costs and promoting sustainable urban growth," highlights Prof. Inazumi.
Lastly, the researchers encourage scientists and urban planners to explore the GHSP system and the energy pile-based integrated approach to promote sustainable urban development.
By bridging the gap between geotechnical engineering and renewable energy, this work lays the foundation for sustainable urban living, and by addressing energy challenges currently faced by humanity, it aims to pave the way for resilient, energy-efficient urban development!
