Which statement best describes both tidal energy and wave energy, and notes an environmental consideration for each?

• A. Tidal energy uses moving water with turbines in barriers or lagoons; environmental: estuarine flow disruption; Wave energy uses surface waves with buoys or buoy arrays; environmental: potential impacts on marine life.
• B. Tidal energy uses solar arrays; environmental: deforestation; Wave energy uses wind turbines; environmental: bird collisions.
• C. Tidal energy uses geothermal wells; environmental: subsidence; Wave energy uses chemical batteries; environmental: leakage.
• D. Tidal energy uses waterfalls to power turbines; environmental: river flooding; Wave energy uses hydroelectric dams; environmental: fish migration.

Answer: (A)

Tidal energy and wave energy both pull energy from moving water, but from different ocean dynamics: tides are the regular rise and fall of seawater, while waves are rolling surface disturbances. Tidal energy captures the flow of water through barriers or lagoons with turbines, turning the moving water into electricity. An environmental consideration here is disruption of estuarine flow, which can change sediment transport, salinity patterns, and habitats that rely on that flushing and mixing. Wave energy devices use surface waves, often with buoys or buoy arrays, to generate power. A key environmental consideration for wave energy is potential impacts on marine life, including interactions with animals and habitats and the noise and physical presence of the devices. The other options mismatch the technologies (solar arrays, geothermal wells, waterfalls, or hydroelectric dams) and pair them with less fitting environmental concerns, so they don’t describe both energy types accurately.