Power Generation

Green-power generation sources reduce significantly the need for fossil-fuel-based electricity generation. Electricity is generated primarily by burning coal and natural gas. While these fuel sources have a lower cost per kilowatt than green-power-generation sources, this will soon cease to be the case. Many observers believe fossil-fuel production will decrease dramatically in the next half-century, and will end completely before 2100. During that period we can expect energy consumption to increase dramatically, driving up costs for fossil-fuel-generated electricity. Cost increases and the ongoing negative environmental effects caused by fossil-fuel use are driving homeowners, businesses, governments and utilities to develop and adopt green-power-generation sources.

Green-power generation is among the most advanced segments of the green-technology market. Several technologies, such as wind and solar power, are commercially available now. Ocean-power technology and hydrogen production from sulfur-deprived algae are in development and prototyping stages. Government incentive programs and a steady stream of investment capital are driving growth in this segment. Investment and research support are expected to increase to match the growing economic and environmental costs of fossil-fuel-generated electricity.

Key Components

Renewables - Renewable energy sources such as wind, water, geothermal steam, biomass and solar provide zero-emission, zero-fuel-cost power to national power grids, commercial buildings and residential units. Efficiency gains in power generation coupled with low-cost scaleable technology are driving growth in this component, and helping it to garner the largest share of investment dollars in green technology. In more established technologies such as wind and solar, investment is migrating into different parts of the supply chain as companies continue innovating to bring down capital costs. Other technologies, such as ocean power, are achieving higher rates of early stage investment, which is driven by the confluence of technology advancements and positive policy climates.

Solar Power - Solar power derives energy from the sun and converts that energy into electricity using photovoltaic (PV) panels or energy-conversion systems. Solar-power technology, while advanced and commercially available, produces electricity subject to available sunlight, making it suitable for peak-power support but unusable as a base-load system.
- Polysilicon - Polysilicon panels and arrays are the most common form of solar-power generation. Polysilicon cells are collections of silicon wafers, made from either monocrystalline or polycrystalline silicon. The most advanced polysilicon cells reach efficiencies of 11 percent to 18 percent, though new production technologies offer higher efficiency possibilities. Most polysilicon cells are only able to capture visible areas of the light spectrum.
- Thin Film - High silicon prices have driven research into non- and low-silicon semiconductor materials, such as copper indium gallium diselenide, cadmium telluride and amorphous silicon. Thin films are less expensive by cost per kilowatt compared to polysilicon, but low efficiencies (5 percent to 8 percent) require large amounts of area for deployment. Thin films are able to capture light in invisible parts of the spectrum and during low-light periods and in low-light areas. The technology involved in manufacturing these materials is complex, and continued research in assembly and production processes are required to bring down costs and increase market share.
  
  Veterans
  
  First Solar United Solar Ovonic Miasolé
  
  XsunX ICP Solar
  
  Startups
  
  Xunlight G24 Innovations Wakonda Technologies
  
  Heliovolt Nanosolar Sierra Solar
- Concentrated PV - Concentrated PV arrays focus light onto polysilicon solar panels to increase the energy intensity and conversion efficiency of traditional PV panels. CPV requires less polysilicon than traditional PV arrays. This technology often employs single- and dual-tracking systems to keep pace with the sun as it moves across the sky.
- Concentrated Solar Power (CSP) & Solar Thermal - CSP and solar thermal reflect energy from the sun onto mirrors, which heats oil or water, and creates steam to power traditional-energy turbine generators. Parabolic trough and dish designs are effective means of concentrating solar heat and converting it into electricity. Excess superheated material can also be maintained in reserve and used to spin turbine generators when sunlight is not available.