Diablo Canyon Nuclear Power Plant, Unitary Tax Revenue, and SLCUSD
(An explanation of decreasing unitary tax revenue and its impact on SLCUSD. For a quick overview of Diablo Canyon Nuclear Power Plant (DCPP) and our schools, please start here. We also have information on the financial impacts of decommissioning. Our school funding overview can be found here.)
Importance of DCPP Property Tax Revenue
PG&E has long boasted about the local benefits DCPP provides to our community, and often highlights its support of our local schools. Historically, most of that support has come in the form of property tax revenue (also called “unitary tax” revenue) paid to SLCO county and SLCUSD based on the taxable value of DCPP.
PG&E’s property tax bill has decreased from $25 million to $9.5 million since 2016.
PG&E claims it will owe only $700,000 annually in property taxes after 2025, since only the land will have any taxable value.
SLO parents and residents have no mechanism for challenging or appealing decisions made by the State Board of Equalization (SBE), which is responsible for assessing the value of DCPP.
What is unitary tax?
For our purposes, unitary tax can be thought of as the property tax paid by PG&E for electric generation facilities located in SLO County (primarily DCPP).
SLO receives unitary tax money from other utilities and railroads, but DCPP is responsible for the majority (70-90%) of unitary tax revenue.
Prior to 2016, SLO County relied on DCPP tax revenue for over 6% of its budget.
How is unitary tax revenue calculated and collected?
In California, property taxes are collected at the county level (the SLO County Assessor collects these taxes locally) and calculated by using an “assessed value” of the property being taxed. As a simplified example, when purchasing a home, the purchase price of the home becomes the assessed value, and the homeowner pays a property tax to the County based on that value (1% is the basic tax rate for personal and unitary property). Property tax revenue is then used to fund the County’s budget each year, with portions also distributed to local school districts.
However, the assessed value of unitary assets are NOT determined by the County. The assessed values for DCPP and PG&E’s other unitary assets are determined at the state level, by an organization called the California State Board of Equalization (SBE). Every year, SBE provides DCPP’s assessed value to the County, which then sends PG&E a property tax bill. PG&E’s DCPP property tax bills for 2017 and 2025 are shown below.
How much unitary tax is PG&E paying for DCPP?
As the tax bills show, the amount has decreased substantially since 2016.
In the 2016-17 fiscal year, SLO County received approximately $25 million in unitary tax revenue from DCPP, with more than $9M going to SLCUSD. In 2024-25, DCPP tax revenue was less than $10 million for the County and less than $3 million for SLCUSD.
Why has DCPP tax revenue decreased so much?
In 2016, PG&E released plans to decommission DCPP, with plant operations scheduled to end in 2025. As a result, the assessed value of DCPP has been steadily decreasing. PG&E claims that after 2026, the assessed value of the plant itself will be zero.
Why is PG&E saying it will not have to pay any property taxes for its assets at DCPP?
This gets into the details of how PG&E assets are assessed for property tax purposes.
In brief, after 2025, PG&E’s unitary assets at DCPP (other than land) will have been fully depreciated for accounting purposes because the plant was scheduled to close on that date. PG&E is claiming that these assets should also be considered fully depreciated for property tax purposes, meaning the company should have to pay property taxes based only on the value of the land the plant sits on. PG&E estimates their upcoming tax bill will be $700,000, whereas in 2024-25 they paid more than $11 million (with over $3 million going to SLCUSD).
Is PG&E correct about its upcoming tax obligations?
The answer to this question is very complicated, but based on numerous conversations with SBE and a review of PG&E’s prior tax bills, we believe NO. However, a PG&E tax attorney has given testimony, under oath, at the CPUC claiming that PG&E is forecasting a tax bill based solely on the value of the land DCPP sits on, and NOT on plant assets.
If PG&E is correct, it would result a huge shock to SLCUSD’s budget, and would require even more severe cuts to educational services.
For more information on the decommissioning process and its impacts on SLCUSD’s budget, please see our Decommissioning and Community Impacts page.