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In page Timeline of solar cells:

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  • 1992 - The PV Pioneer Program started at Sacramento Municipal Utility District (SMUD). It was the first broad based commercialization of distributed, grid-connected PV system ("roof-top solar") It became the model for the later CA Million Solar Roofs Program.[4]
  • 1992 - University of South Florida fabricates a 15.89% efficient thin-film cell.[citation needed]
  • 1993 - The National Renewable Energy Laboratory's (NREL) Solar Energy Research Facility is established.[citation needed]