The level of D4 Renewable Identification Number generation required to meet the final US Renewable Volume Obligations in 2026 and 2027 will have to reach unprecedented levels, according to a new study by the University of Illinois.
The research findings follow the Environmental Protection Agency's late March announcement of its final "Set 2" rule establishing RVOs under the Renewable Fuel Standard for 2026 and 2027.
RINs are compliance credits that function as the "currency" of the RFS program.
In an article that first appeared on FarmdocDaily on Monday, a website hosted by the University of Illinois, economists projected that required D4 net RIN generation must increase from 7.10 billion RIN gallons in 2025 to 11 billion to 12 billion RIN gallons in 2026 and 2027.
"Those are levels that have no precedent in the history of the US biomass-based diesel industry," the economists said.
In their article, the economists examined the recent monthly pace of D4 RIN generation alongside the pace required to meet the final RVOs.
"In short, the required D4 net RIN generation is the crucial number that the biomass-based diesel sector must hit in each of the next two compliance years, and the cushion provided by the RIN bank is essentially exhausted after 2026," the economists stated in the article.
The economists analyzed D4 RIN net generation from January 2023 through the latest available 2026 data and compared it with the average monthly pace of D4 RIN net generation required to satisfy total D4 demand in each calendar year.
"The required monthly pace was 652 million RIN gallons in 2023, rose to 758 million RIN gallons in 2024, and fell to 592 million RIN gallons in 2025. Under the final Set 2 rule, the required monthly pace jumps to 916 million RIN gallons in 2026 and 991 million RIN gallons in 2027. RIN generation incorporates both imports and domestically produced biomass-based diesel," the economists said.
The article noted that the biomass-based diesel sector must shift to monthly D4 RIN generation levels. However, aside from one transitory exception, this level has not been achieved in any month over the past three years. The sector would then need to sustain these levels for 24 consecutive months.
So far, monthly D4 RIN net generation in early 2026 has remained well below the pace needed to meet the 2026 RVO.
The latest available data show monthly D4 RIN net generation of 436 million gallons in January, 478 million in February, and 649 million in March 2026, according to FarmdocDaily.