U.S. Department of Energy - Energy Efficiency and Renewable Energy

Wind and Hydropower Technologies Program

Hydropower Research and Development

The United States faces many challenges as it prepares to meet its energy needs in the twenty-first century. Electricity supply crises, fluctuating natural gas and gasoline prices, heightened concerns about the security of the domestic energy infrastructure and of foreign sources of supply, and uncertainties about the benefits of utility restructuring are all elements of the energy policy challenge. Hydropower is an important part of the diverse energy portfolio that is needed for a stable, reliable energy sector in the United States.

Responding to these national energy issues, DOE recently restructured hydropower R&D, which is now organized around two primary areas:

• Enhancing the viability of hydropower — developing new, cost-effective, advanced technologies that will have enhanced environmental performance and greater energy efficiencies. When implemented, these technologies will enable a 10 percent growth in hydropower generation at existing plants.

• Expanding the application of hydropower — providing supporting research in power systems integration, resource assessment, innovative technology characterization, valuation and performance metrics, industry support, and technology acceptance.

Current R&D

While hydropower turbine manufacturers have incrementally improved turbine technology to improve efficiencies, the basic design concepts haven't changed for decades. These late 19th and early 20th century designs did not consider environmental effects, since little was known about environmental effects of hydropower at the time.

During the 1980s, the environmental concerns in the United States became more important in hydropower projects, both existing and planned. This trend is slowly spreading across the globe.

The hydropower industry recognizes that hydropower plants have an effect on the environment. The industry also recognizes that there is a great need to bring hydro turbine designs into the 21st century. The industry visualizes innovative hydro turbines designed from a new perspective. This perspective would look at the "turbine system" (which could include everything except the dam and powerhouse) to balance environmental, technical, and economic considerations.

Environmental Challenges

Although hydroelectric power plants have many advantages over other energy sources, the potential environmental impacts are also well known. Most of the adverse impacts of dams are caused by habitat alterations. Reservoirs associated with large dams can cover land and river habitat with water and displace human populations. Diverting water out of the stream channel (or storing water for future electrical generation) can dry out streamside vegetation. Insufficient stream flow degrades habitat for fish and other aquatic organisms in the affected river reach below the dam. Water in the reservoir is stagnant compared to a free-flowing river, so water-borne sediments and nutrients can be trapped, resulting in the undesirable growth and spread of algae and aquatic weeds. In some cases, water spilled from high dams may become supersaturated with nitrogen gas and cause gas-bubble disease in aquatic organisms inhabiting the tailwaters below the hydropower plant.

Hydropower projects can also affect aquatic organisms directly. The dam can block upstream movements of migratory fish such as salmon, steelhead, American shad, sturgeon, paddlefish, and eels. Downstream-moving fish may be drawn into the power plant intake flow and pass through the turbine. These fish are exposed to physical stresses (pressure changes, shear, turbulence, strike) that may cause disorientation, physiological stress, injury, or death.

R&D is currently underway that will help fishery biologists and turbine designers better understand what is happening in the turbine passage. Biological tests are being conducted that will quantify the physical stresses that cause injury or death to fish. In addition to these tests, tools are being developed to help both the engineers and biologists. These tools include developing a Sensor Fish, which is a "crash dummy fish." It will be able to measure the physical stresses in a turbine passage and can be used instead of live fish to gather information. Another tool is the development of a computational fluid dynamics program that models potential fish behavior in the turbine passage. The test results and tools will help turbine manufacturers design a more environmentally friendly turbine, which will reduce the physical stresses to which fish are exposed. New products such as greaseless bearings eliminate the possibility of petroleum products being released in the water.

Read more about DOE's research.

Hydro Turbine Development

In the mid-1990s, the U.S. Department of Energy began research into advanced hydropower technology. The goal is to develop systems that generate more electricity with less environmental impact. DOE funded the conceptual designs of four turbine types: a redesigned Kaplan and Francis turbine, a dissolved-oxygen-enhancing turbine, and a new turbine type that borrows technology from the food processing industry. The image shows what the new turbine design would look like.

This new turbine design proceeded into the proof-of-concept stage for biological and engineering tests. Part of the proof-of-concept was to verify the biological design assumptions and the issue of whether the results of biological testing of a smaller model can be scaled upward to a full-sized turbine.

Many of the turbine manufacturers have begun designing environmentally friendly turbines, based on a potential market not only in the United States, but also worldwide. In 2002, DOE selected three projects where environmentally friendly turbines will be installed and tested. Two projects involve improving downstream fish passage and one involves increasing dissolved oxygen in discharged water. Other federal agencies and utilities are conducting research into hydropower plant operation to improve fish habitat.

Read more about DOE's research.

Future of R&D

The Hydro R&D Forum was held in 2001 to develop an agenda for hydro industry research and development activities worthy of pursuit in the years ahead. The forum brought together representatives from various parts of the hydro industry.

R&D needs were identified and prioritized by the following topic areas:

• Performance and Production
• Environmental Issues
• Innovative Operations and Maintenance (O&M)
• Multi-Purpose Values
• Human Resource Issues

The top issues in each area were then prioritized. Below are the top ten industry R&D needs identified in 2001:

1. Quantify and Communicate Hydropower's Value Compared to the Power Mix

   Needs include developing objective criteria for measuring and valuing hydropower's non-power attributes. Criteria should be based on internationally recognized standards, should permit comparisons across generation sources, recognize emissions as well as effects on aquatic and land resources, and take into account the entire life cycle of facilities associated with electricity production.

2. Continue Advanced Hydro Turbine Development and Deployment

   Achieving progress on advanced hydro technology, which aims to reduce mortality of fish passing through turbines. Recommended new areas of emphasis include water quality improvement without compromising energy generation efficiency.

3. Develop Business Model for O&M Decision Support Based on Condition Monitoring

   Condition monitoring equipment and systems are increasingly being used. However, the availability of new information poses the conundrum of how to optimally use this information for making both major and minor business decisions in support of facilities operation and maintenance.

4. Improve Methods to Quantify Costs and Benefits from Ancillary Services

   Hydro plant owners and operators recognize that the ancillary services often provided by their facilities are valuable; however, market structures often fail to appropriately recognize these values. As a consequence, returns to owners and projects are often less than they would be if these values were appropriately acknowledged.

5. Communicate with Stakeholder about Hydropower

   There is a need to ensure that constituencies are suitably informed about hydro issues. In this area, there are needs to identify effective educational methods and content, research the best ways to transfer knowledge, update and maintain factual content and methods, and develop communication networks to inform policymakers, non-governmental organizations, and the public.

6. Support Green Power Acceptance for Hydropower

   In some regions, electricity is marketed as "green," meaning it is generated from sources that are environmentally beneficial compared to the alternative. Projects in this area include determining how to gain acceptance for hydro within green marketing programs.

7. Develop Hydropower Competency Management Program

   Workforce issues are increasing in priority, especially because of loss and projected loss of personnel due to retirements. Projects in this area include those that focus on inventorying the skills and competencies that are needed for hydro facilities operation and developing techniques and strategies for addressing identified needs.

8. Promote Hydro-Related R&D Technology Transfer

   Much information is available that is, or may be, applicable to problems and areas of need. However, better tools and processes are needed for communicating and sharing information, both from research activities and operational experience.

9. Determine Operating Life Effects Due to More Severe Load Operations

   In recent years, many hydro projects have begun operating in ways not envisioned during their original design. Work is needed to determine how equipment is affected, and also to identify actions and tools for predicting and preventing failures.

10. Develop Protocols for Measuring Mitigation Effectiveness

    In recent years, hydro project owners have engaged in many instances of implementing environmental mitigation measures. However, it is generally not known whether the measures have been effective. Knowledge gained from research in this could help in designing future mitigation measures and could help to avoid ineffective mitigation.

Visit the Program Areas section to read more about the federal government's R&D efforts in hydropower.