Sunflowers have much more potential for humanity than just delivering pretty flowers and sunflower oil as Dr. Erika Nehnevajova explained to the Planet strikes back AG of Schiller Gymnasium in October 2019. Based on her research in the university of Bern, sunflowers are capable of removing heavy metal contamination from soil more efficiently than the invasive soil washing procedure. As an added bonus the sunflowers concentrate the heavy metals in small amounts in their leaves and stems. The sunflowers can then be harvested and small amounts mixed with other organic material, which can then be used as biofuel.
This procedure has not yet been carried out on an industrial scale but as agricultural land becomes scarcer and the demand for renewable energy rises, maybe this concept will become more viable .