Urban Vibro Trucks will thump city streets for geothermal options

A new simulation video from Herrenknecht AG shows off its Urban Vibro Trucks. The machines can deploy thumping devices from their mid-sections that send seismic waves beneath city landscapes to explore the terrain for geothermal development.

Geothermal development is coming on strong. Just a few months ago, Google announced that its advanced geothermal plant in Nevada was operational. A cutting-edge method of drilling for geothermal wells announced last month shaves 70% off previous drilling times. And also last month, it was revealed that an enormous geothermal energy jackpot might lie beneath the floor of our oceans where tectonic plates come together.

The basic idea of geothermal energy is that you shoot water deep into the ground where it's hot. That water picks up the heat and comes back to the surface where it transfers it to a working fluid that turns to steam which turns some kind of turbine to produce electricity.

While it's an incredibly clean way to produce power, finding areas where both underground heat sources and the geology are suitable for use can be challenging. In wide open areas like some parts of Utah, where the Google project is based, using equipment to send seismic waves into the ground is relatively easy. But in cities that could really benefit from boosts of clean geothermal energy, getting that equipment set up is a whole different story.

Enter the Urban Vibro Trucks from Herrenknecht AG, a German company that specializes in underground tunneling technology. The trucks are being developed in collaboration with the Geophysical Institute of the Karlsruhe Institute of Technology (KIT).

Each truck bears eight wheels and has an all-wheel-drive system in which the front four wheels can move independently of the back four, giving it exceptional maneuverability in tight city streets. It also comes equipped with all the usual smart safety features including a collision-awareness system and birds-eye-view camera system. It weighs 32 tons, operates at a modest 65 dB and can reach speeds of 40 km/h (25 mph). It's also approved for use on the road in the EU.

Thumpers

But where the trucks really shine is their ability to deploy a thumper device known as a P-wave shaker from beneath the vehicles. This shaker sends seismic waves into the ground beneath it and a mesh network of geophone sensors records the waves that bounce back, providing a detailed map of the environment beneath cities. The hope is that this map will provide enough data to bring geothermal systems into urban settings.

"The new mobile Urban Vibro Truck´s shaker provides broad frequency band capability with high peak force output at low frequencies," said the company. "Improved system design brings better source signal quality that leads to deeper penetration depth compared to state-of-the-art products."

Not only are the trucks notable for their high-tech geothermal spotting abilities, but they are also expected to overcome bureaucratic roadblocks as well.

"The German government plans to identify up to 100 potential sites for geothermal energy," Herrenknecht's Axel Langer told us. "As seismic investigations have been limited in Germany, there is a high demand for suitable equipment. Many campaigns currently fail due to lengthy and complicated regulatory procedures. With our truck, these hurdles would be significantly reduced, as it resembles a municipal vehicle and is therefore better suited for urban environments."

Langer added that the shakers on the trucks are due to undergo testing in collaboration with KIT in June of this year. That will be followed by the deployment of a prototype vehicle in the last quarter of the year. If that field test is successful, serial production of the trucks is due to take place in early 2025.