Construction and early history The plant was constructed by the
Long Island Lighting Company (LILCO). Unit 1 was constructed in 1948, and Unit 2 in 1950. The land was previously part of the Alfred K. Woodhull estate. Units 3 and 4 were commissioned in 1958 and 1960. KeySpan was acquired by
National Grid in 2007. In 2001, LIPA proposed building two mini-turbines at Port Jefferson as part of a plan to build ten such plants across Long Island to avoid the risk of
rolling blackouts in the face of increased demand like
those experienced in California the previous year, given strain on the system from
a heat wave in 2001. The pair of turbines was under an 80 MW threshold that would have triggered a full regulatory and environmental review. The adjacent
Village of Poquott sued over the lack of environmental review, but the new turbines were completed by August 2002.
Later history In 2014, National Grid proposed replacing the plant with a new
combined cycle power plant. In the mid-2010s, Village of Port Jefferson officials opposed construction of a new unit at
Caithness Long Island Energy Center for fear that it would make it harder to
repower and easier to decommission the Port Jefferson plant. The village filed lawsuits against Caithness that were dismissed in 2015 and 2016. By 2020, the plant's utilization was so low that it met one study's criteria for being a
peaking plant, an inefficient use due to the steam units' long start-up times. Another 2020 report commissioned by the village opposed decommissioning the plant, citing opportunities as a supplement to renewable power mandated by the state
Climate Leadership and Community Protection Act, as the center of a potential
microgrid operated by the village, or as a site for a new
battery storage power station. Port Jefferson Power Station was also subject to challenges against the power plant's tax assessment. LILCO had initiated challenges against several plants including Port Jefferson in the early 1990s, but these were dropped in 2004 after they had been inherited by LIPA. LIPA reinstated these challenges in 2010. In 2015, the Village of Port Jefferson and the
Port Jefferson School District sued LIPA on the basis of a claimed 1997 agreement between then-Governor
George Pataki, local school districts, and LIPA not to seek to lower the assessed tax value. This mirrored an earlier suit filed by the
Town of Huntington and
Northport–East Northport School District about the corresponding situation at the
Northport Power Station. The
Town of Brookhaven and Village of Port Jefferson settled with LIPA in December 2018 to reduce the plant's tax payments over the course of the following nine years. The Port Jefferson School District initially decided to appeal the decision, but reversed this decision the following March. == References ==