A World First: Swansea Bay Tidal lagoon in review

Abstract

By 2020, the UK is legally obliged to meet 20% of its electrical demands with renewable sources [1]. Currently, renewable sources account for as little as 5%, meaning drastic action is required to meet this target [2]. The UK is also committed to reduce CO 2 emissions by 60% by 2050 [3]. Using clean energy is not just important to help combat climate change, but also to allow the UK to have more control on its energy. With the decline of the North Sea oil and gas industry, there is more and more reliance on importing these fuels through costly negotiations. Furthermore, being in control of our energy sources and especially with renewable energy, the cost for electricity can be stable and independent of any price fluctuations or politics. The UK is fortunate with an abundance of renewable energy options, including the greatest potential for tidal energy in the world. This type of energy holds an important advantage over other forms of renewable energypredictability. With comprehensive tide data for years in advance, any tidal energy project can have a known output the national grid is able to plan for. The successful utilisation of tidal energy alone could provide in excess of 20% of the nations energy demand [4]. The repeated proposals for the Severn barrage since the 1920's have proved the necessity to evolve techniques used for tidal range generation, with each proposal turned down due to high costs and environmental concerns [5-7]. Other UK sites that have been investigated for a barrage scheme also include the Solway [8,9], Mersey [10], Loughor, Duddon, Wyre and Thames Estuaries [11]. However, unlike Swansea Bay lagoon, these projects are not currently progressing. Currently the most advanced project in the UK is the Swansea Bay Tidal lagoon, which is making rapid progress and will hopefully be generating electricity in 2019. The power generated would be able to provide energy for approximately 155,000 homes [12]. As the project is the first of its kind in the world, its construction would send a clear statement of the UK's commitment to clean, renewable energy. The aim of this paper is to bring together the current and existing information regarding tidal lagoon developments while focusing specifically on the planned Swansea Bay Lagoon. 2 Background/Tidal Lagoons Tidal lagoons are a new concept based on the adaptation of an existing, proven technologytidal barrages. Like any tidal range project the success is heavily dependant on the chosen location and with Swansea Bay being part of the

Optimal Site Selection of Tidal Power Plants Using a Novel Method: A Case in China

“…Potential effects on fish, particularly migratory species, may arise through mortality at the turbines or delayed passage, as has been found at Annapolis [49]. Fortunately, since the development of the first bulb turbine there has been significant advancements in fish friendly technology [56].…”

An exploitation plan of tidal power in the Severn Estuary

“…The coastal-facing lagoon-walls will be built around the low water mark, no more than one mile from the coast, basically avoid the inter-tidal area. Bridgewater Bay, one of the further lagoon sites, is entirely outside the inter-tidal area, in fact according to a report commissioned by a study group in 2004, a lagoon construction in Bridgewater Bay can somehow help reducing the salt erosion problems thus protect the shoreline [15]. In terms of bird habitats, the lagoon walls covered with plants can be treated as isolated island, which might somehow provide additional staging post for migratory birds.…”

“…However, water engineering experts believe that the constructing of Swansea Bay lagoon and Bridgewater Bay lagoon can also play an important role in flood defending. With the existence of lagoons, the government will be able to control the water level in it to protect the vulnerable coastal area from extreme flooding, storm surge and any other wave actions [15].…”

Review of Tidal Lagoon Technology and Opportunities for Integration within the UK Energy System

“…A second concern is the cost of the structure and the amount of government funding required to make the project commercially viable [46]. At the moment of this writing (July 2017), no decision has been made by the UK government on the funding agreement.…”

“…According to [52], Kaplan turbines will be deployed for the tidal lagoon projects: this technology is the same used at other tidal plants, with modifications such as "triple regulation" that allows a more optimized efficiency curve [46].…”