Tidal energy is one of the most promising renewable energy sources because the oceans are always flowing and the flow increases and decreases with the tide. This regular change makes harvesting this energy as simple as placing a turbine near or at the mouth of a river or harbour.
On a small scale, individual homes and small businesses can use a pond or reservoir as a tide-energy generator. In larger-scale projects, entire regions and countries can use the power of the seas for their benefit.
The Rising Tide
Harvesting tidal energy is not a new idea; the concept was first proposed in the 19th century. Back then, people were more interested in using the energy produced by the tides for industrial purposes such as manufacturing and mining. Even now, some people still use tidal energy for these purposes although it’s mainly been replaced by other sources of power.
Over the past century, engineers and scientists have developed more efficient methods for harnessing tidal energy; this includes using machines and devices that turn the flow of energy into usable electricity. Modern tidal turbines have a much higher capacity than their predecessors, allowing them to generate more electricity. This, in turn, makes them more reliable and cost-effective.
How Does It Work?
Like most other renewable energy sources, tidal energy is based on the principle of extracting usable energy from water. The key difference is that instead of using the energy of the sun, wind, or other naturally occurring phenomena, tidal turbines harness the energy of the oceans.
During low tide, the gravitational pull of the Moon and Sun combined with the natural currents in the oceans cause the water to flow towards the beach. This makes the energy of the tides most valuable during this time as the waters are at their lowest. At this point, the water covers only a small area of the land and there’s plenty of room for turbines to collect the energy; this makes low tide the ideal time for generating power.
The opposite is true during high tide. The gravitational forces are weaker and opposite in direction to that of low tide, causing the water to flow out to sea. This makes the energy of the tides less accessible at this point and it’s more beneficial to place the turbines in larger bodies of water such as lakes and the ocean. The flow of the water increases the pressure on the turbine and as a result, the energy it produces. This is why most of the current commercially available tidal turbines are located at the mouth of a river, next to a beach or coastal area. The location of these turbines maximises the opportunities for drawing in water and the pressure it puts on the turbine. This, in turn, maximises the amount of electricity that can be generated by the device.
Where Can I Use It?
The location of tidal turbines is not random and is primarily dictated by the location of the nearest body of water. The closer the body of water, the more valuable the energy it can provide. Rivers, inlets, and lochs (lakes) are all common places where one can expect to find tidal turbines as the water flows in and out of these locations regularly.
Tidal energy can also be found in tidal pools and marshes which are particularly useful for smaller scale projects and individual homes. The water in these locations is at its highest during the spring tide and the lowest during the neap tide. The fact that the energy is derived from a renewable resource means that it’s available whenever they’re needed. This makes them ideal locations for generating power.
Tidal energy is, in other words, a gift from the oceans that can be used to provide clean and sustainable energy for homes, businesses, and communities. If you’re interested in deriving power from the tides, where should you look?