First a warning: This column is going to use words I haven’t written, read or used in decades: “numerator and denominator.”

The words come up because of questions raised by Hawaii’s well-publicized new law that is to make us the first 100 percent renewable energy state by 2045.

The “100 percent” label clearly appears to be one of the easiest issues to both like and understand. Too bad it is way more complicated than a simple shot of happy news.

Last week, after Gov. David Ige announced the state’s new opposition to running Hawaii power plants by burning liquefied natural gas, the news set off a round of praise for Hawaii from the environment-focused news media.

Newsweek captured the misinformation best as it gushed, “Hawaii’s utilities must generate 100 percent of their electricity from renewable sources.”

That is not accurate; what Hawaii must do is comply with a new state law that says the “renewable portfolio standard shall be 100 percent on Dec. 31, 2045.”

The renewable portfolio standard (RPS) is a formula, which, if you must know, is: (Utility renewable energy + rooftop solar)/net sales = RPS.

Net sales are defined as gross demand minus rooftop solar.

Henry Curtis, Life of the Land executive director and long-time local energy observer, said the new law “is being marketed as something that it does not do.

“Oil, coal and natural gas can still be used to generate electricity in 2046 and beyond.”

Yes, even though coal, oil and gas are not renewable, they will still be in use in Hawaii in 2045 even if Hawaii makes it to 100 percent.

Now get ready for the N and D words.

“The RPS percentage is a fraction, with the numerator equal to the amount of renewable generation on the system and the denominator equal to utility sales. One thing that is not clearly understood is that the numerator and denominator are not defined in the same terms. The numerator is generation. The denominator is sales,” explained Carl Freedman, Regulatory Reform Working Group Chair of the Hawaii Energy Policy Forum.

It all seems complex to the extreme, but the result, as Curtis explained, is that a renewable standard does not mean renewable energy.

“An RPS of 100 percent occurs when the kilowatt- hours of rooftop solar generated equals the kilowatt- hours of fossil fuel derived electricity sold by the utility.

“Ironically, the more rooftop solar produced, the higher the amounts of fossil fuel-derived electricity that can be sold by the utility,” Curtis said in an interview.

State Rep. Chris Lee, the Kailua Democrat who chairs the House Energy Committee and helped write the new energy law, said it is still working well.

“I think a very small percentage will come from fossil fuels in 2045 and I think we are going to beat the goal by several years,” Lee said in an interview.

Energy observers add that Hawaii, under this formula, could have more than 100 percent of its renewable energy portfolio generated by non-carbon-based fuel, which is both a good thing and also why journalists have a basic mistrust of long division.

Richard Borreca writes on politics on Sundays, Tuesdays and Fridays. Reach him at rborreca@staradvertiser.com.