For a long time, tidal energy has been lurking behind the British renewable energy arsenal, and its position has surpassed that of wind energy and solar energy counterparts, partly because of early technical preparation and high cost.
However, recent research shows that it can provide 65,438+065,438+0% of Britain's electricity demand-plus the government's massive investment in British project pipelines-and its future looks brighter and brighter.
Tide is a large-scale movement of water around the earth driven by the gravity of the sun and the moon. In areas where the tide is particularly strong, we can use turbines-similar to wind turbines, but underwater-to spin when the water passes by to get some energy. At present, this method is more popular than the previous idea of using tidal barrage similar to dam, mainly because its impact on the environment is not so serious.
In the past decade, the global tidal energy industry has proved that it is predictable and reliable to absorb energy from the ocean. In Scottish, Welsh, Canadian, China, French and Japanese countries, more than a dozen experimental turbines have been designed to generate electricity, many of which supply electricity for homes and businesses.
Britain's first "commercial" tidal energy project, led by developers SIMEC Atlantis and Nova Innovation, installed multiple turbine arrays in Scottish seawater. The largest one can generate 6 MW of electricity at present: this is about the equivalent of two or three onshore wind turbines, providing enough energy to supply thousands of households. The expansion of the project is already in progress. In the Faroe Islands, the tidal development company Minesto has just announced an array plan of 120 MW, which will provide 40% of the island's energy demand.
The design trend of tidal turbines is usually separated by a big question: whether they are best floating or installed on the seabed. Floating turbines are easier to maintain, and they benefit from faster water flow near the water surface. But those turbines on the seabed are less affected by storms, and ships can sail freely on them in deep enough water. It is not clear whether a method will win or whether the choice depends on the location.
Anyway, since the tidal power generation industry has mastered the feasible technology, it needs to prove that it can reduce the cost. Fortunately, there is a precedent for the story of offshore wind power generation. With the support of British and other local governments, offshore wind power developers around the world have reduced their costs by nearly one-third in the past decade, and it is expected that the costs will be further reduced due to ongoing research and development.
The cost of tidal energy may never be as low as wind energy. This is partly because tidal turbines cannot be scaled up like wind turbines (you can only build such a large turbine in a limited water depth range) and partly because doing things on the seabed is usually more expensive than doing things on the sea surface (this is a worse and more inaccessible environment). But matching costs may not even be necessary.
As critics are keen to point out, the wind is not always blowing, the sun is not always shining, and the trend is not always flowing: therefore, in order to build a flexible low-carbon power system, we need to use a series of different energy sources, rather than relying only on the cheapest energy.
Tidal energy provides a unique advantage, that is, although its output will change with time, this change can be predicted several years in advance by knowing the orbits of the earth and the moon. This means that grid operators will be able to plan different outputs of tidal turbines and arrange other sources to fill the gap.
Fortunately, the British government seems to be stepping up efforts to help the tidal industry. The latest round of "contract for price difference" renewable energy financing in Britain contains "partial" tidal energy, so there is no need to compete with cheaper technologies such as offshore wind power at present. The recently announced British energy security strategy promises to "actively explore" tidal energy and geothermal energy technologies.
Tidal energy will never play an important role on a global scale like wind or solar energy, because only a few areas in the world have strong tides. Unfortunately, it will not be ready in time to help us cope with the current energy price crisis.
But for those places where the trend is strong, including Britain, it has great prospects. Some analysts estimate that the global market size is 654.38+030 billion pounds. In addition, it is possible to further develop turbine technology to take advantage of slower but more stable ocean currents, such as the Kuroshio current off the coast of Japan.
Tidal energy technology is effective and it will continue to exist. Now, the most effective way to provide electricity for our homes and businesses is to build more tidal power stations.