Diamond Bearings Protect Hydroelectric Systems in Remote Himalayan Villages

The Himalayan Mountains tower over some of the most rugged terrain and harshest climate conditions on the planet. Melting snows from Mount Everest, K2 and hundreds of other snow-capped peaks carve out more than 6,000 rivers in Nepal, China, Bhutan, India and Pakistan. The vast majority of people living along these remote rivers and valleys survive in under-developed living conditions in geographically isolated areas. Like most developing countries, basic services—like heat and electricity—are scarce and inconsistent. Homes and schools in tiny villages do not have reliable electricity. Only a few homes have small solar panels that provide power for one or two lights. Small stoves, burning animal waste or scarce wood resources provide the heat and cooking for villagers. Unfortunately, connecting these small communities to existing power grids and centralized power is cost prohibitive.

Hydroelectric Power

To combat the scarcity of reliable power, a team of private companies and nonprofits—including Advantage Products, New Energy Corporation, World Wildlife Fund, Himalaya Currents, Inc., among others—developed a local, sustainable, clean energy system that could provide Himalayan villages with continuous power. The clean energy project relies on an in-stream hydrokinetic power-generation system submerged in a flume in a nearby river. The 5-kilowatt system converts kinetic energy in the river's water current to electrical power. The pollution-free electricity is then transmitted to the village. The clean energy project uses the flow of the river to keep the hydrokinetic turbine rotors constantly spinning. The generator's simple design provides clean and continuous power with an extremely small environmental footprint. The industry's first above-water direct-drive generator coupled with the water-lubricated, long-lasting diamond bearings in the underwater turbine rotor eliminate environmental contaminants like grease and oil. Because snow melts throughout the year in the high Himalayas and flows down into the expansive river system, villagers have access to a significant, consistent potential energy. Hydroelectric power generation is more reliable and, in many locations, more easily accessed than other renewable energy sources like wind or solar. The rivers in the Himalayas offer one of the largest, untapped green energy power sources in the world. The first system will be installed at the remote mountain village of Ringmo. Ringmo is on the shores of Lake Phoksundo in the Shey Phoksundo National Park, high in the Dolpa region in Nepal. A suitable location along the river was chosen in April 2013.

Diamond Bearings

The remote location presented significant logistical challenges for transporting, installing and replacing equipment. Most of the components had to be transported by porter or pony caravans. The system needed to be as simple and light as possible. Underwater abrasion and wear posed the biggest challenges for the hydrokinetic system, especially the turbine's rotor. The melting ice from Himalayan glaciers is laden with abrasive sediment. As water moves downstream in Himalayan rivers, it picks up more and more debris and sediment. These abrasive particles can quickly destroy standard sealed bearings and wear components on traditional turbine rotors. A challenging issue facing applications running in abrasive operating fluids is the ongoing threat of seal and bearing failure. A typical sealed bearing must be kept clean and lubricated in order for the pump to operate appropriately. Even the smallest break in the bearing seal can quickly flood the bearing with abrasive working fluids—disrupting operations and quickly bringing the pump to a halt. The project's underwater turbine rotor was designed to work with diamond bearings. Abrasive-laden, water environments that are challenging to traditional sealed bearings generally provide ideal conditions for diamond bearing technology. The bearings are particularly resistant to abrasive particles that can cause accelerated wear. They also can carry the load and accommodate the speeds in a compact, simple design that permits process fluid lubrication—greatly reducing the need for seals.

Sustainable Energy

Once completed, the project will generate 24-hour power, easily handling fluctuating energy loads without losing a lot of energy in the transmission process. Diamond bearings will make the generator virtually maintenance free. The small hydrokinetic system will provide power for needed light and satellite connection to an isolated, ecologically sensitive area of the world.