Currently, coal is the main energy source for electricity generation, accounting for 39%.
This is the second most used energy source for electric generation, accounting for 27%.
Third highest source of energy for electricity in the U.S., supplying 19% of the current demand.
Despite all the marketing and media attention, photovoltaic solar power supply less than 0.4%.
STE / CSP
Similar to PV solar, Solar Thermal Energy or Concentrating Solar Power, has a small percentage at less than 0.4%.
Wind power has been the fastest-growing source of electricity generation for several years, suppling 4.4% of today's total demand.
With an estimated potential electricity generation of 31,300 TWh (760% of the annual demand), this source accounts for only 0.4% of current consumption.
Besides some experimental projects in California, this energy source has not been commercialized in the U.S. electricity sector.
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Hydro-power supplies 6% of the current electricity demand. This renewable energy source lacks support in the environmental community because of its adverse impacts on ecosystems (both upstream and downstream from the dam).
Biomass has a total estimated potential electricity generation of 500 TWh (12% of the annual demand). However, today it only supplies 1.7% of total demand.
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