Opportunity… desalinate ocean water with zero energy use. Problem… deal with brutal corrosion environment of the sea surface at low cost. Solution… Hot-dip Galvanized Steel! When you think of an ocean buoy you probably imagine a big navigation buoy or maybe a little lobster trap buoy. Oneka Technologies has a different vision of what a buoy is. They build Desalination buoys that use ocean wave action to desalinate seawater and then pump it to shore.

Desalination is a solution to a problem as old as mankind itself, lack of clean fresh water. Coastal areas have turned to desalination to address fresh water shortages for decades. Unfortunately, there are many problems with traditional desalination processes, primarily economic and environmental. Every cubic meter (about 260 gallons) of desalinated water requires 3 to 25 kW/h of energy. This energy consumption means pollution and CO2 generation. Also, these desalination plants produce noise, consume valuable coastal land and generate highly saline outflows that can calcify the immediate shoreline.

Enter Oneka and their desalination buoy. Each buoy uses reverse osmosis to desalinate about 2,500 gallons of seawater a day with zero energy use, zero land use and zero pollution. A big technical challenge for the engineers was to build the buoy that supports and powers all the desalination equipment. It had to be very strong and very corrosion resistant to survive the brutal environment of the open ocean surface. The salt water and air, incessant wave action and boat impact during installation and servicing all challenge any design. 

Earlier versions made with painted steel failed miserably and other metals proved far too costly and/or fragile for this difficult application. Hot-dip Galvanizing with its long-proven record in marine environments was a logical possibility. Careful co-ordination between the client and the galvanizer optimized the design and the natural qualities of pure zinc shine in practice with a service life that will outlast the mechanical systems within the buoy.

The end result is a system of ocean buoys that produce almost a million gallons a year per buoy with zero energy needs and therefore each buoy saves about 75,000 lbs of CO2 emissions annually. Hot-Dip contributes strongly by greatly extending service life at almost no additional upfront cost. This is doubly critical in green energy industries where higher costs are often the deal breaker.