Secretive energy reserves are concealed beneath the America's surface

Secretive energy reserves are concealed beneath the America's surface

The United States Geological Survey (USGS) has recently conducted an assessment on the potential for geothermal energy in the western United States, particularly in the Great Basin region. This region, spanning Nevada, Utah, California, Idaho, Oregon, and Wyoming, holds a vast, untapped energy reservoir that could revolutionise America's energy landscape.

According to the USGS, these energy reservoirs are referred to as 'enhanced geothermal systems' (EGS). The assessment finds a much larger energy reservoir than previously known, one where heat is trapped in dense, impermeable rock layers miles below ground. The USGS estimates that these geologically active states could yield up to 135 gigawatts of continuous, reliable geothermal power - enough to meet the steady energy needs of around 135 million average US homes.

Current advancements in EGS technology are making this potential a reality. Leading companies like Fervo Energy are pioneering these advancements by utilizing oil and gas techniques to optimise reservoir stimulation and power generation efficiency. If successfully developed, geothermal energy could become a major pillar of America's low-carbon future.

To tap into EGS, engineers would need to drill deep (in some cases over 6km or 3.7 miles) and fracture the rock to allow water to circulate and absorb heat. The heated water can then be pumped back to the surface to generate electricity, offering a constant source of power that doesn't rely on the weather.

Despite the promise of EGS, it supplies less than 1% of America's electricity, with most of it coming from conventional hydrothermal systems. No commercial-scale enhanced geothermal plants are yet in operation in the US, despite pilot projects showing promise across the Great Basin.

The US Department of Energy aims to tackle the cost obstacle through its Enhanced Geothermal ShotTM programme, seeking a 90% reduction in the cost of the technology by 2035. Key challenges remain in scaling EGS, including cost reduction, supply chain build-out, subsurface uncertainties, and grid integration.

The USGS's work has wider benefits beyond energy production, as it helps identify geothermal, critical mineral resources, and groundwater. The newest surveys of the subsurface by the USGS help identify both geothermal and critical mineral resources. The USGS assessment does not limit its focus to the Great Basin and considers other regions with potential geothermal energy resources.

Dr Sarah Ryker, acting director of the USGS, stated that USGS assessments of energy resources are about the future and focus on undiscovered resources yet to be fully explored. The USGS's next focus is the Williston Basin in North Dakota, another region with hidden geothermal promise.

In conclusion, EGS development in the U.S. is at an inflection point with technological progress, strong policy and investment support, and growing market demand aligning to enable its transformation into a major clean energy source by mid-century. However, overcoming cost, scale, and technical uncertainties remains essential to realise this potential fully.

[1] Geothermal Energy Program [2] USGS Geothermal Resources Program [3] Fervo Energy [4] DOE's Enhanced Geothermal ShotTM Program

1. The United States Geological Survey's (USGS) Geothermal Resources Program is currently examining the potential for geothermal energy in the western United States, particularly the Great Basin region, which holds a vast, untapped energy reservoir.
2. This energy reservoir, referred to as 'enhanced geothermal systems' (EGS), has a much larger energy potential than previously known, with heat trapped in dense, impermeable rock layers miles below ground.
3. The USGS estimates that these geologically active states could yield up to 135 gigawatts of continuous, reliable geothermal power - enough to meet the steady energy needs of around 135 million average US homes.
4. Leading companies like Fervo Energy are pioneering advancements in EGS technology, using oil and gas techniques to optimize reservoir stimulation and power generation efficiency.
5. The US Department of Energy's Enhanced Geothermal ShotTM Program aims to tackle the cost obstacle, seeking a 90% reduction in the cost of the technology by 2035.
6. Despite promising pilot projects in the Great Basin, no commercial-scale enhanced geothermal plants are yet in operation in the US, and key challenges remain in scaling EGS, including cost reduction, supply chain build-out, subsurface uncertainties, and grid integration.

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