UAV-based thermal imaging and heat output estimation of a coastal geothermal resource: La Jolla beach, Baja California, Mexico

The exploration of unexploited geothermal resources is required to encourage the use of renewable energy. This study focuses on La Jolla beach, Ensenada, Mexico. The beach hosts a thermal anomaly with temperatures of up to 52 degrees C at the surface and up to 93 degrees C at 20 cm depth. The objectives were to: map the thermal anomaly, understand the impact of tides, quantify the thermal water discharge rate and heat output, and discuss a direct use of the energy. The mapping was performed with Unmanned Aerial Vehicles equipped with optical and thermal cameras at two different dates. Additional temperature measurements were performed with a thermocouple, while the total fluid discharge was estimated from flow measurements. A comparison between the campaigns indicated that the highest surface temperature area was more than three times larger in 2019 than in 2018 (259 m(2) vs. 69 m(2)). Such change was due to the tidal range and associated hydrostatic pressure variations. The total thermal water discharge is 330 +/- 44 L s(-1), which corresponds to an advective heat output of 40.5 +/- 5.2 MWt. The use of this energy in a Multi-Effect Distillation desalinization plant can contribute to cover the shortage of freshwater in Ensenada. (c) 2020 Elsevier Ltd. All rights reserved.

Automated summary

This study focuses on the exploration of unexploited geothermal resources at La Jolla beach in Ensenada, Mexico, revealing a high potential for development. By mapping and analyzing the thermal anomaly using drones and thermocouples, it is found that utilizing this energy source can help alleviate the freshwater shortage in Ensenada.