MAKAPUU, Hawaii -- Higher gas and diesel fuel prices boosted the popularity of locally made biodiesel, but people hoping to save money on the environmentally friendly fuel are out of luck because there is no longer enough to go around.

The shortage of bio-diesel means only a handful of Maui drivers are benefiting from its low cost.

Pacific BioDiesel on Oahu and Maui uses waste cooking oil to make diesel fuel cheaper than petroleum refineries can make gas. Now, bio-diesel is so popular it is using up all the waste oil available.

"We really could use many times more oil, much more oil than we've got coming in right now," said Bob King of Pacific BioDiesel.

On Maui, the product is so popular there is a waitlist for new customers, especially since Pacific BioDiesel kept its price down to $3.79 a gallon. That is about $1.50 a gallon cheaper than petroleum diesel.

However, on Oahu, Pacific BioDiesel's product is distributed by Union 76 stations and priced close to regular diesel at $4.99.

A customer from Maui told KITV he was shocked to pay so much more on Oahu than he would on Maui.

"That's a big jump you know. That's $1.20," customer John Toetuu said. "Somebody making some money."

One good thing about pricing biodiesel at nearly $5 a gallon is that if it was priced at the Maui price, it would sell out in just a few days because all the waste oil is already being used.

That is why Pacific BioDiesel's founders were watching oil being squeezed out of various seeds Thursday. They were looking for potential new bio-diesel raw material. They hope coconuts or kukui nuts might work.

"So they are not going to be invasive to the islands. They are not going to bring in unknown bugs and stuff like that," said Kelly King of Pacific BioDiesel.

Even if federally funded tests show promise, the Kings said the lack of government support before this means Hawaii is still years away from growing our own fuel.