Our ancestors knew when to plant by looking at it, ship captains navigate by it, and wolves howl at it… and now its draw will power our cities. After solar power, moon power – or more exactly tidal power – is well positioned to provide a sustainable, limitless power supply for years to come.
Like lots of great energy solutions, the idea of using the tides for energy is not new. The earliest evidence of man tapping into the power of the moon dates back to the Middle Age when power was typically used for grinding grain. Today, the concept of tapping into the moon’s energy has remained the same, but technology has greatly advanced and improved. Despite certain inevitable disadvantages, which are also commonly found in other renewable sectors, there are plenty of excellent reasons why the power industry is eagerly developing tidal power making it a viable energy source.
The first clear benefit comes from tidal power’s nature – an almost limitless source of clean energy. The IEA predicts that by 2050 ocean energy might produce up to 337 GW of power, which will have the potential of reducing C02 emissions by up to 1 billion tonnes. According to the UK Marine Foresight Panel, if we could capture just 0.1% of the total of the ocean’s kinetic energy caused by tides, we could satisfy the current global energy demand five times over. Indeed, it’s scalable and limitless…. as long as the tides keep flowing.
These are big numbers but not unheard of when you look at renewables. Yet, unlike wind or solar power that is heavily dependent on weather, tides are cyclic. This predictability provides great stability to the grid. On any given day we can predict exactly how much power will be produced from any given tidal plant. Low fluctuation also means longer equipment life cycles and thus lower maintenance cost.
And wait it gets even better. While no one really wants a giant wind turbine in his or her backyard, a tidal turbine sits at the bottom of the ocean, out of sight, out of mind. Also, in the long-term, the financial benefits of tidal power are substantial. In other words, electricity generated by tidal schemes, once matured, will likely be less expensive than other forms of energy generation.
In an even bigger picture, harnessing tidal power on large or utility scale could also improve a nation’s energy security*. Large-scale tidal energy could generate power in-line with economic developments and environment needs.
A current example of such a project is Swansea Bay in the UK, which has attracted 100 million British pounds from investors in October to build a power-generating tidal lagoon. This emblematic project marks a cornerstone for building tidal power as one of the key renewable energies of the future.
*Energy security is defined by IEA as the uninterrupted availability of energy sources at an affordable price.