Forty years later, ERI is making President Kennedy's dream a reality by rapidly changing the economics of seawater desalination. ERI's Pressure Exchanger® (PX®) technology has reduced by a factor of ten the energy wasted in the process used in Kennedy's Guantanamo plant. Today, ERI's PX® technology enables plant operators to produce potable water from seawater with an energy consumption of less than 2.0 kwh per cubic meter (8 kwh/1,000 gallons).

 How Saddam Wanted it-The Baghdad-Kuwait Connection

The roots of ERI can be traced to Leif Hauge, a Norwegian inventor, working in the early 1990's at a the Kuwait Institute of Scientific Research (KISR) laboratories. In 1990 when Saddam invaded Kuwait, Saddam's people were looking for advanced technology at KISR. Only the action of the quick-thinking researchers destroying key documents prevented the technology from falling in the hands of the invaders. This, however, did not prevent Mr. Hauge from being abducted and becoming a prisoner of war in Baghdad. At the end of the war the inventor was repatriated to the US and ERI was born.

ERI's technology is an improvement on reverse osmosis -- a widely used process in which seawater is pressurized to approximately 70 bar (1,000 PSI) and pushed through polymer membranes. Part of the water permeates the membranes and leaves all the salt behind. The remaining salty brine contains as much as 185% of the energy required to do the desalination.

Engineers designing modern seawater desalination plants using reverse osmosis have utilized Pelton wheels to try to recover this energy. The problem is that the Pelton wheel is a technology developed in 1850 and in its best modern execution, using advanced materials and computer designs, it can never be more than about 80% efficient. Typically when operating conditions change from design, Pelton devices in reality are much less than 80% efficient. This leaves a lot of the energy from a desalination plant literally going down the drain. Further, Pelton wheels are made of metal, which often suffers severe erosion and corrosion problems when exposed to high velocity seawater jets.

When he founded ERI, Mr. Hauge's idea was to develop a positive displacement pump that would recycle the energy inherently wasted by the reverse osmosis process. This type of pump had the potential to recover the brine energy with an efficiency of over 95%. However, Mr. Hauge tried for three years to make his device out of stainless steel, titanium and other fancy alloys but the metal parts would all gall and seize because seawater is such a poor lubricant.

The Invention - ERI PX®

Oak Ridge National Laboratories said it could not be done. By 1995 the inventor gave up trying to construct his pump from metallic parts and was intrigued by the potential of ceramics as a better approach. At this point Mr. Hauge got in a plane to consult with Oak Ridge National Laboratories, who at the time was considered to be among the leading experts of ceramic technology in the world. After looking at the challenge for several days, the experts at Oak Ridge told the inventor it was impossible because it was too difficult to manufacture to such fine tolerances.

Undaunted, Mr. Hauge continued to tinker in his laboratory and by 1997 he had several small, commercial ceramic devices installed in medium desalination plants in resorts and hotels in the Canary Islands. By late 1999 he had installed dozens of these small ceramic devices saving energy in smaller and medium desalination plants worldwide. Five US patents were granted along the way. Some of these devices have been operating for close to seven years with no maintenance.

Enter the Super Plumbers

By early 2000, it was clear to the founding investors of ERI that this technology had the potential to change the economics of desalination. However the device needed to be introduced to an industry, which is very conservative in adopting new technology. Even more challenging, desalination plants were getting larger and larger and the development of a much bigger device was required to address these larger plants.

ERI's strategy was simple: get the technology out on the market by re-plumbing existing plants with the device so that the operators could realize the big savings right away. The result was that by late 2002 ERI had close to 500 devices installed in the market and the prototype of the larger units in beta- testing. ERI is now a profitable enterprise and sales are running at over ten times the rate they were in the year 2000.

The New ERI large rotor Pressure Exchanger Device

Since late 2002, ERI has been shipping in quantity a large diameter ceramic device capable of handling the needs of a 1,000 ton per day desalination plant (250,000 gallons per day) in a single unit. These ceramic devices called Pressure Exchangers® can be arrayed in parallel to work in large installations. With this technology it is now possible to produce pure desalinated seawater cheaper than, for instance, the cost of pumping silty water, full of fertilizers and pesticides over the mountains from the Colorado River. As a result desalinated seawater is now so cheap that it is being used in Spain and Israel for agricultural purposes and the demand for desalination plants is growing at over 30 percent per year.