Complex sentence: In order to be economically viable, projects must do much better than just being competitive head-to-head with oil, they must also be profitable, and generate a sufficient return on investment to justify the capital investment in the project.
Split into simpler sentences: In order to be economically viable, projects must do much better than just being competitive head-to-head with oil. They must also generate a sufficient return on investment to justify the capital investment in the project.