When you think about it, it makes sense. The tide comes in and out multiple times per day, it’s always moving and water is much denser than air (creating more force on the turbines)… so why aren’t we lining the ocean floors with Tidal Barrages, Tidal Fences, and Tidal Turbines??
Not so fast…
Even through there seems to be great potential here, we’re not there quite yet. Yes, there are a few great things about tidal energy and power:
Tidal energy is a renewable energy source. Compared to fossil fuels and nuclear reserves, which will run out at some point (theoretically), the gravitational pull from the sun and moon aren’t going away any time soon.
Tidal power is environmental. From what we can tell, it doesn’t emit any climate gases and takes up relatively little space.
Tidal currents are very predictable. The tide comes in and out on well-known and well-documented cycles. That means it’s easier to construct the system with right dimensions, knowing what kind of powers the equipment will be exposed to.
Tidal power is effective at low speeds. As I mentioned earlier, water is much denser than air. 832 times denser to be exact. That’s what makes it possible to generate electricity at low speeds.
However, here’s why tidal power is still a fraction of total power production:
We don’t know what we don’t know. Yes, I mentioned it’s environmentally friendly. It doesn’t emit climate gases. But we still don’t know the full environmental impact yet, so we’re playing it safe.
It’s too close to land right now. As of now, tidal power plants need to be constructed close to land in order to take advantage of the stronger tidal currents. They’re still working on technology to harness weaker tidal currents, at locations further out to sea.
And last, but not least, it’s too expensive. Money seems to always be the problem! Rough projections estimate tidal power will be commercially profitable around 2020. Not too far away… but not here yet.
So should we be using tidal energy? Yes and no. We’ll have to wait and see.