This technical brief analyzes the performance of triple-junction solar cells on a mobile robot. Although originally designed for satellite use, it is demonstrated that triple-junction cells are effective in terrestrial applications. This makes them particularly suitable for systems with limited size and mass but high-power requirements such as a mobile robot. A testing station was specially constructed to characterize triple-junction and conventional silicon cell performance in different environments and to compare their effectiveness. Additional field tests were carried out with an autonomous robot in order to check the ability to deliver sufficient power to varying loads. Results show that they surpass conventional technologies with efficiencies higher than 22%, so they can be considered as an alternative technology for power sources on board of terrestrial mobile robots.