About Us


Thirty years ago, the United States dominated magnesium production, making half of the world supply with a healthy export market. Most of the magnesium was made from seawater or water from the Great Salt Lake.
China (90%) and Russia (4%) are now the top producers. In 2022, U.S. production of this USDOE Critical Material for Energy fell to less than 2% of global output after the last U.S. producer declared force majeure. For a time, we couldn’t make beer cans because magnesium is part of most aluminum alloys, including the one for cans. Magnesium is also used for steel desulphurization and to make titanium metal from titanium chloride.
Magnesium is used in nearly all U.S. military vehicles, particularly aircraft. In order for automakers to increase usage of magnesium for lightweighting, the supply must be stable, free of geopolitical risk, create zero environmental harm, and have zero embodied carbon. Tidal Metal will be first to market with magnesium meeting all of these criteria.


Magnesium can be cost-effectively extracted from seawater using Tidal Metals' deep technology. GreenBlu has patented technology to extract magnesium chloride using a temperature-swing adsorption vapor pump without adding any chemicals into the seawater. The same technology is used to create anhydrous MgCl2 feedstock for electrolysis. Several novel technologies are innovatively combined to create an unlimited supply of low-cost, decarbonized magnesium, the lightest structural metal, using only seawater and electricity. Decades faster than terrestrial mining, we are unlocking the two billion megatons of magnesium that is dissolved in the oceans.

Magnesium metal is the lightest structural metal, weighing 75% less than steel and 33% less than aluminum. Producing magnesium from seawater or desalination waste brine can greatly accelerate decarbonization by lightweighting transportation and enabling hydrogen storage. In 2025, the world is projected to produce 100 million cars and light trucks, weighing about 180 megatons, much of it being steel. About 15 gigatons of CO2 will be emitted over the lifetime of those vehicles. If we can replace 40 megatons of steel with 10 megatons of magnesium, we can reduced emissions by over 1 gigaton. As we move into more energy intensive mobility such as electric flight and space travel, the effects of lightweighting amplify even further. This is Tidal Metals' mission.

Meet Our Team

The co-founders at GreenBlu have extensive experience as research scientists/engineers or technical marketing and business development. Each team member has more than 15 years of experience in deeptech product development or technical sales. Our multi-disciplinary understanding of market fit, science, and manufacturing uniquely qualifies us to bring our sustainable seawater magnesium to market. 

Dr. Howard Yuh

Ph.D. '05, Nuclear Engineering, MIT

Chief Executive Officer

Dr. Yuh founded GreenBlu in 2016 after years of independent research into enabling materials and how to better utilize lower exergy energy. He is a nuclear engineer and material scientist by training, and has expertise in thermal cycles, adsorption physics, and pressure/vacuum systems. He served as a member of the inaugural class of the DOE Oppenheimer Science Energy Leadership Program in 2016, was a winner of the CleanTech Open NE business accelerator in 2016, and was one of six startups in the CleanTech2Market in 2017.

Dr. Ethan Schartman

Ph.D. '08, Astrophysics, Princeton

Chief Technology Officer

Dr. Schartman received his PhD in Astrophysics from Princeton University in 2008. His dissertation involved the designing of rotating sheared flows of both water and a liquid gallium alloy.

Dr. Kevin Tritz

Ph.D. '02, Engineering Physics, U. Wisconsin, Madison

Chief Operating Officer

Dr. Tritz received his PhD in Engineering Physics from the University of Wisconsin–Madison in 2002. He has worked on system analysis and design, instrumentation and process control, and machine learning algorithms in fusion energy research for over 20 years.

Mr. Duncan M. O'Brien Jr.

MBA, Stanford

Chief Financial Officer

Mr. O'Brien has 40 years of experience as a business leader, having served multiple senior leadership roles at Goldman Sachs, GE, and Cox. His core expertise are teambuilding, strategic planning, and finance.