# Thermal reaction of the subsurface on the operation of a geothermal planar trench collector

## TL;DR

This paper describes an experimental setup to study how a geothermal heat collector interacts with the surrounding subsurface during thermal operations.

## Contribution

The novel contribution is the detailed setup and measurement data from a vertically installed planar geothermal heat collector.

## Key findings

- The experimental plant includes three types of temperature measurements and subsurface property monitoring.
- Data acquisition systems and calibration procedures were thoroughly described.
- Thermal response test data from the planar heat collector were collected and analyzed.

## Abstract

In order to develop and analyse ground heat collectors, experimental plants with reliable measurement data are needed. Here, an experimental plant with a planar ground heat collector installed vertically in a trench is presented. The ground heat collector is extensively equipped with measurement technology installed to track its thermal behaviour and that of the surrounding ground. This includes 3 different types of temperature measurements as well as the determination of the volumetric water content and the bulk electrical conductivity of the subsurface near the collector. The description also includes detailed information on the geometry of the experimental plant and the sensors installed, the data acquisition systems used and information on measurement accuracy and calibration procedures. Measurement data collected by these sensors during a thermal response test on the planar ground heat collector are described.