Low temperature solar thermal energy system for energy generation and desalination

在我们的星球上，太阳能是一种丰富的可再生资源。将太阳能转化为热能是目前利用这种资源最有效的方式。然而，集中式太阳能发电厂使用反射镜将太阳能集中在一起产生高温，成本很高，需要安装大型设备。平板收集器今天在120摄氏度的温度下效率为50%，是一种潜在的具有成本效益的解决方案。这里的问题在于将这些低品位的热量转化为可用能源。在南安普顿大学，我们最近开发了冷凝发动机(CE)-一种使用水作为工作介质的热机，工作温度为100摄氏度。发动机使用蒸汽的冷凝和产生的真空作为驱动力，而不是蒸汽的压力。它在大气压下运行，因此安全问题最小。使用蒸汽膨胀可使效率达到10%或更高。与平板集热器相结合，CE有可能开发出一种简单、经济、模块化的太阳能热系统，该系统可以从冷凝过程中产生电力和淡水。在这个项目中，我们将开发一个用于发电和海水淡化的太阳能热能系统的理论框架，目的是评估其整体生产率。针对冷凝器这一关键部件，建立了理论模型，为其优化设计提供了理论依据。在此基础上，将建造一台100瓦的试验性发动机并进行测试。最近的理论工作表明，通过冷凝过程中的热回收，可以增加30-35%的功率输出，增加70%-80%的水生产。这将导致一个新颖的两阶段能量转换循环，并将大大提高该系统的成本效益。热回收冷凝过程将在实验室中开发、建模和测试。该项目将产生一个具有新颖、高效和成本效益的组件的优化太阳能和海水淡化系统。该项目与荷兰代尔夫特的SyNext有限公司合作进行。该系统的简单性及其模块化特点意味着它也非常适合在迫切需要能源和清洁水的发展中国家部署。这方面也将与SyNext有限公司合作进行探索。

On our planet, solar energy is an abundant renewable resource. The conversion of solar into thermal energy is currently the most efficient way to use this resource. Concentrated Solar Power plants, which use mirrors to focus the solar energy to generate high temperatures, are however costly, and require large installations. Flat plate collectors, which today have efficiencies of 50% at a temperature of 120C, are potentially a cost effective solution. The problem here lies in the conversion of this low-grade heat into usable energy. At Southampton University, we recently developed the condensing engine (CE) - a heat engine which employs water as working fluid with an operating temperature of 100C. The engine uses the condensation of steam and the arising vacuum as driving force, rather than the pressure of steam. It operates at atmospheric pressure, so that safety issues are minimal. The use of steam expansion gives an efficiency of 10% or more. In combination with flat plate collectors, the CE has the potential for the development of a simple, cost-effective, modular solar thermal system, which produces electricity as well as fresh water from the condensation process. In this project, we will develop a theoretical framework for a solar thermal system for electricity production and desalination with the aim to assess its overall productivity. For the key component, the condensing engine, a theoretical model will be developed.as basis for its optimisation. Based on the results, an experimental 100 Watt engine will be built and tested. Recent theoretical work suggests that through heat recovery from the condensation process, the power output can be increased by 30-35%, and the water production by 70 to 80%. This would lead to a novel, 2-stage energy conversion cycle and would improve the cost-effectiveness of the system substantially. The heat-recovery condensation process will be developed, modelled, and tested in the laboratory.The project will result in an optimised solar thermal energy and desalination system with novel, efficient and cost-effective components. The project runs in cooperation with Synext Ltd., Delft/Netherlands. The simplicity of the system, and its modular character mean that it would also be well suited for deployment in developing countries where there is an urgent need for both energy and clean water. This aspect will also be explored in cooperation with synext Ltd.