RENEWABLE ENERGY
SOLAR PLANTS
HEAT STORAGE IN
Tim Bruewer details optimal thermal management for the use of molten salt in solar thermal power plants with concentrated radiation
At a CSP plant, sunlight is concentrated by mirrors onto a central tower, which absorbs the light and transfers the heat to a liquid energy source inside the tower
‘Green Deal’ was presented by the EU Commission in 2019, defining the climate neutrality of 26 member states up to the year 2050. Among other methods, the focus is on solar energy as an important representative in this area. Solar thermal power plants with concentrated solar power (CSP), in particular, often offer higher efficiency than photovoltaic systems. To compensate for the fluctuating production of electricity due to changing solar radiation, molten salt is often used for heat storage in such plants. However, if the temperature of the melt falls below a limit of approximately 228°C, conventional
T 36
www.engineerlive.com
he demand for environmentally friendly and low-CO2
forms
of energy generation has been increasing in Europe since the
salt compounds “freeze,” which can block lines. On the other hand, if the temperature is too high, at around 585°C, the salt dissolves and can no longer be used as a heat carrier. In addition, leakage can occur at the valves, reducing efficiency and increasing the likelihood that the melt will freeze. Terefore, extensive heat management is necessary to ensure that the temperature of the salt is stable. Tis can be achieved by a heating system consisting of electrical heating modules, sensors, and control units to stabilise the temperature of the molten salt at any point in the plant. In recent years, social and political
movements have led to an increased focus on renewable forms of energy in the countries of the European Union. According to data from the Energy
Industries Council (EIC), more renewable energy projects are currently being planned and implemented in the EU area than in any other region in the world. Te same applies to solar thermal generation with concentrated radiation (CSP) in particular, which, in contrast to now controversial wind energy, is characterised by particularly low environmental impact. Te European Solar Termal Electricity Association (ESTELA) puts the number of ongoing systems in Europe at 2,385, with a further 588 systems being planned. Spain, for example, as the European pioneer of solar thermal energy, is working on new legislation that aims to launch new projects by 2024. However, to make this form of energy generation sustainable and at the same time economical, it is necessary to optimise efficiency on the one
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52
