What characterizes a sustainable energy project?

A sustainable energy project is characterized by its aim to generate energy with minimal environmental impact. This involves utilizing renewable resources such as wind, solar, or hydropower, which contribute to reducing greenhouse gas emissions and preserving natural ecosystems. The focus on minimal environmental impact also means that social considerations, such as community effects and fair practices, are taken into account.

While energy efficiency and low-cost production are important elements in the broader context of energy use and policy, they do not specifically define sustainability. A project might be energy efficient or low-cost but still have a negative environmental impact if it relies on fossil fuels or harmful practices. Thus, the key characteristic is the balance between energy generation and environmental stewardship, making option B the most appropriate choice.