Your mention of fuel from vegetable waste in the feature on Piedmont Biofuels ("8 Days a Week," Dec. 19) gave the impression that its product is entirely plant-based.
According to Piedmont Biofuels leader Lyle Estill, only a small portion ("several hundred gallons a week") comes from waste vegetable oils, produced at the co-op in Moncure. The bulk ("closer to 25,000 gallons/week"), from the industrial facility in Pittsboro, uses waste chicken fat.
Anyone thinking that they're doing the planet a favor by purchasing biodiesel from Piedmont Biofuels should look a little more closely at it. The confusion over biodiesel feedstocks results directly from information presented by Piedmont Biofuels. With repeated references to plant oils on its main Web pages, and without a specific statement otherwise, the term "multi-feedstock" can easily be assumed to mean different plants. While animal fat is mentioned in Piedmont Biofuels' blogs, the theme of the upfront presentation is sustainability of plant-based energy.
For example, the lead paragraph on the "Our Story" page states: "From the beginning, Piedmont Biofuels has focused on small-scale biodiesel production. Our expertise lies in small reactor design for making fuel out of waste vegetable oil."
Then, the "Education" section touts "Vegetable Oil as Alternative Fuel," with reference to it in a separate pdf file. There are many other examples.
The use of animal feedstocks financially aids the producers of them by providing one more revenue stream, allowing them to avoid disposal costs—whether it is the main item produced or incidental to the production of some other. If you purchase a product, you support its production.
Given the energy-intensive (typically petroleum-based) nature of raising meat, and the inefficiencies of conversion of plant protein to animal protein (with the associated waste of water and land), animal-derived biodiesel is not eco-friendly. If Piedmont Biofuels is earnest about promoting alternatives to an unsustainable energy policy, it seems contradictory that it would formulate animal-based biodiesel.
Editor's note: The Independent article specifically referred to a tour of the Piedmont Biofuels co-op in Moncure, where vegetable-based biodiesel is produced.