A.) After installation, the energy is produced is free
C.) No greenhouse gases are produced
D.) It is a renewable source of energy
Step-by-step explanation:
Once a tidal power scheme is in place and functioning, it creates no greenhouse gas emissions at all and because the systems are being designed to run for 30 or more years without replacement or major routine maintenance, the impact of the initial build is easily mitigated.
Another advantage is that it is estimated that tidal power will be useful to humans for at least 2 billion years, making tidal power as renewable as wind and solar. The only major problem facing these systems is maintenance over the long term.
However, tidal energy can only be produced in coastlines.