A Pathway to Sustainability Jobs: Water Technology

Today we have great challenges before us, a recession and for some communities a depression. Women earn on the average 80% of what a man earns. And for African Americans and Latinas, as you know, the gap is even greater.  For African American women, 71 cents and Latinas, 62 cents for each dollar that a man makes.

 Many women live paycheck to paycheck as you know. Green jobs is a way that we can help women increase their income and we must make sure that all women are included as part of the recovery, including women of color, and that all women are adequately represented in the ranks of women in green jobs.

As we honor the women who have shaped our nation, we must remember that we are tasked with writing the next chapter of women’s history.This is what we’re doing here with HOPE4GREEN, helping write the next chapter in the struggle for economic opportunity and security for all women.

In this post, it will introduce water technology jobs in the Green Economy sector.  


Water Tech

Water technology is the action of using a multitude of systems to utilize the ocean and freshwater environments to harness energy. Water technologies such as hydropower are classified as renewable sources of energy.  Water technology sources of energy are restored naturally through the water cycle. Water Technology is a renewable source of energy, which is considered a clean alternative to fossil fuels because of it’s natural ability to replenish.

Hydropower

Hydropower is currently the most popular form of water technology in the energy sector. Installation of  hydropower systems do not require the use of fossil fuels because the force of moving power propels a turbine that generates electricity. Businesses eventually make a profit off of water technology sources because the primary cost are the construction and operation of the facilities.

Water technology jobs are

  • Record operational data, personnel attendance, or meter and gauge readings on specified forms.

  • Add chemicals such as ammonia, chlorine, or lime to disinfect and deodorize water and other liquids.

  • Clean and maintain tanks, filter beds, and other work areas using hand tools and power tools.

  • Collect and test water and sewage samples, using test equipment and color analysis standards.

  • Maintain, repair, and lubricate equipment, using hand tools and power tools.

Globally, hydropower accounts for about 19 percent of electric generation. In 2011, U.S. hydropower plants had a capacity of about 100,000 megawatts (MW) and produced 3.25 percent of the total energy and 63 percent of renewable electricity in the United States. Although most suitable sites for large scale dams have been developed in the United States and globally, there are many opportunities to install hydropower systems at existing dams currently without generation capability, and to use other water energy technologies in rivers, tidal zones and open ocean. According to two 2012 studies by the U.S. Department of Energy, existing dams that are not currently producing power could provide 12,000 MW of additional capacity, and if new installations (including those harnessing waves and tidal currents) are built, hydropower could potentially provide 15 percent of America’s electricity by 2030 (vs. 6 percent today).

Rivers

Dams

Large hydropower dams on major rivers are the most developed generators of water energy. Large dams also meet multiple societal needs such as irrigation, flood control and recreation.

There are several drawbacks to reservoir plants. Studies suggest that large reservoirs in boreal and tropical climates emit as many greenhouse gases as a fossil fuel power plant. Flooded vegetation decomposes, releasing methane and carbon dioxide in a large burst at the beginning of a dam’s life and continuing in lesser amounts throughout the dam’s use. Further impacts include changes in water temperature, dissolved oxygen and other nutrients, harm to the river’s ecosystem, displacement of communities by the alteration of the river’s flow, and riverbank instability leading to deforestation, flooding, and erosion. Hydropower is vulnerable to climate change. Prolonged droughts may diminish the water level of the river, lowering electricity generation, while melting glaciers, rapid snowpack melt, or changes in precipitation patterns from snow to rain may significantly alter the river flow.

Run-of-the-River

Run-of-the-river plants have no water storage facilities but may use low-level dams to increase the difference between the water intake level and the turbine. In this case, the natural river flow generates electricity and the amount of power generated fluctuates depending on the cycle of the river. Although run-of-the-river technology can be used for large scale power generation, it is commonly applied to supply individual communities with electricity, with capacities of less than 30 MW. This form of power generation is popular in rural areas of China, but has potential application in many places, including in the United States. Run-of-the-river technology typically disrupts much less of the river flow as compared to large hydropower dams.

Current

Current generation works similarly to a wind turbine, but underwater. Because water is denser than air, water moving at a given speed will produce much more power than that generated by a comparable wind speed. However, the turbine itself must be stronger and, therefore, is more expensive. The environmental impact of current turbines is not clear. It could harm fish populations but fish-safe turbines have been developed.

The United States has many potential sites where current generation could occur, and several projects are underway, including those in the East River in New York and the San Francisco Bay. The Federal Energy Regulatory Commission issued the first U.S. commercial tidal energy pilot project license in 2012. The 10-year license sets the East River (Roosevelt Island Tidal Energy) project on a path towards building 30 turbines to generate 1 MW.

Oceans

Tidal Barrage

Ocean tidal power harnesses the predictable cycle of energy produced by the tides. A tidal barrage works similarly to a large hydropower reservoir dam, but it is placed at the entrance to a bay or estuary. The retained water in the bay is released through turbines in the barrage and generates power. A tide must have a large enough range between high and low tide, about ten feet, for the barrage to function economically. The best potential sites are located in northern Europe and the U.S. West Coast. A tidal barrage in La Rance, France has been operating since 1967 with a capacity of 240 MW. The potential environmental impact of barrages could be significant because they are built in delicate estuary ecosystems, but less intrusive designs such as fences or floating barges are under development.

Tidal Current

Similar to river current technologies, turbines anchored to the ocean floor or suspended from a buoy in the path of an ocean current could be used to generate power. Although this technology is in the development stages, some potential locations in the United States include the Gulf of Maine, North Carolina, the Pacific Northwest, and the Gulf Stream off Florida.

Wave

As wind moves over the surface of the ocean, it transfers energy to the water and creates waves. Although variable in size and speed, waves are predictable and are constantly created. In U.S. coastal waters alone, the total yearly wave energy is 2,100 terawatt hours.

A variety of technologies are being tested to convert wave energy into electricity. Most systems capture energy on the surface of waves or use pressure differences just below the surface. These systems use the swells of waves to create pressure and move hydraulic pumps or pressurized air, which in turn puts generators into motion. The environmental impacts of wave generators are not fully known, but are thought to be minimal and site-specific.

The best potential sites for wave generation are ocean areas with strong wind currents. These areas are between 30° and 60° latitude, polar areas with frequent storms, areas near the equatorial trade winds, and the west coasts of continents. Hybrid wind and wave technology for offshore energy farms are in development. Potential sites in the United States for hybrid wind-wave energy farms include the coastal areas of the East Coast and the Pacific Northwest.

Ocean Thermal Energy Conversion

Ocean thermal energy conversion (OTEC) uses steam produced from warm surface water to spin generating turbines. Cold deep ocean water condenses the steam back into water for reuse. A 36°F temperature difference is necessary between the surface and deep water. Potential sites include tropical islands. OTEC is in the early development stage and is not yet cost-effective, due to the high cost of pumping deep water to surface generating stations. OTEC can be paired with ocean thermal air-conditioning systems (see below). Furthermore, the nutrient-rich deep water can assist in aquaculture. Surface ponds pumped with deep water can cultivate salmon, lobster, and other seafood as well as plankton and algae.

Ocean/Lake Thermal Air-Conditioning

In addition to generating electricity, water also can be used for direct thermal energy. Water from lakes or oceans can provide air-conditioning for buildings. The cold deep water is used to chill fresh water that circulates through a building in a closed-pipe system, providing air-conditioning at a lower cost than traditional methods. The spent water is returned to the ocean or lake to renew the cycle. The cold deep water must be between 39°F and 45°F and close to shore to be economical. Examples of ocean thermal cooling systems are seen in Hawaii (co-located with OTEC facilities), and Toronto, where water from Lake Ontario is used to air-condition downtown buildings. Large-scale OTEC project (100 MW+) situated in island communities such as Puerto Rico, Hawaii or Guam can be economically viable. A 10-MW closed cycle OTEC pilot system is currently under construction in Hawaii, the plant is set to become operational in 2013 and cost over $13 million to build.

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