G-1 by Rigel Carson
The Guardian of Earth series, book 1

This series is set 50 years in the future on Earth. Though some things have changed, humanity is still in a power struggle to control the world's resources. That's not all. Other worlds are interested in this frontier planet.
[NOTE: The digital format of G-1 is published through Kindle Press. Muddle House put out the print format.]
A powerful secret society on future Earth ruthlessly hunts for the keystone, an object of great power, now believed to be held by reclusive but off-the-charts brilliant scientist Dr. Zeke Landry. While searching for his missing uncle, Zeke falls into his enemies’ snare. His chances of escape are slim to none, but he’s not a quitter. Neither is his android assistant. Together they battle the secret society and seek to unravel the mystery of the world’s missing water. One thing’s certain, the clock is ticking. Time’s running out for Zeke … and the world.
[NOTE: The digital format of G-1 is published through Kindle Press. Muddle House put out the print format.]
A powerful secret society on future Earth ruthlessly hunts for the keystone, an object of great power, now believed to be held by reclusive but off-the-charts brilliant scientist Dr. Zeke Landry. While searching for his missing uncle, Zeke falls into his enemies’ snare. His chances of escape are slim to none, but he’s not a quitter. Neither is his android assistant. Together they battle the secret society and seek to unravel the mystery of the world’s missing water. One thing’s certain, the clock is ticking. Time’s running out for Zeke … and the world.