Fresnel solar power plant, Spain

New technology for cost-effective solar power

We have built the first solar thermal power plant with Fresnel reflectors in Almería, the sunniest town in Spain. The feasibility of the everyday use of new technology will be demonstrated in this test plant, which is as large as a typical power plant collector module. The operation of the plant is also competitive and we are therefore expecting the trial operation of the plant, which will be run for two years, to show that it operates very efficiently. The aim of the plant is to produce evidence that electricity can be generated more competitively and prove that Fresnel technology is commercially viable for large scale projects from 2008 onwards. The demonstration power plant, which has a 100 metre long collector, generates one megawatt (peak) of thermal power and is designed as a modular system. In large-scale power plants, several of these modules will be connected up in series. The pilot plant has been built in collaboration with Solar Power Group. Their Fresnel design has already proved itself to be an innovative and economically interesting option for use in solar thermal power plants in two BMU-funded research and development projects. Both companies are now aiming towards making Fresnel collectors usable in commercial steam power stations. The following leading institutions are supervising the scientific aspects of the test plant: the Fraunhofer Institute for Solar Energy Systems and the German Aerospace Center (DLR). Fresnel technology itself will be further improved and developed based on measurements taken at the demonstration plant. MAN Ferrostaal is managing the construction and operation of the plant, both as investor and project manager.

An Overview

Project	FRESDEMO Fresnel demonstration power plant
Plant capacity	1 megawatt (peak) of thermal power from a reflector area of 1433 m²
Location of the plant	Plataforma Solar (PSA), Almería (Andalusia), Spain
Scope of the work	Project management, construction, operations management, maintenance
Investment partner	German Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU)
Engineering partner	Solar Power Group (SPG), responsible for planning, dimensioning and basic engineering of the project
Testing	Fraunhofer Institute for Solar Energy Systems (ISE), German Aerospace Center (DLR)
Completion date	July 2007
Duration	2 year-long trial operation

Catching the sun's rays with new technology

Fresnel technology, which is now being tested under actual operating conditions, is comparatively simple to manufacture, build and operate. The reflectors, which collect and focus the sun's rays, are completely flat and, arranged in a linear pattern, they form long, moveable rows of mirrors. The parallel mirrors focus the radiated energy from the sun onto a pipe, positioned eight metres above the mirrors. Water flows through this absorber pipe, which is heated to temperatures of up to 450 degrees centigrade. This produces steam (as in a conventional power plant), which is converted into electrical energy in a steam turbine. Fresnel collectors are innovative in that they are not sensitive to wind and require a smaller area of land than previous solar collectors. Almería in Spain provides the best conditions for a demonstration plant for this technology as the sun shines here for around 3000 hours a year.

Trial run to proof

To date there has been no experience of using Fresnel collectors under actual operating conditions. In order to ensure and prove that this technology is ready for use in later commercial plants, we decided to build a complete demonstration plant - the same size as a collector module, which would be used in a solar power station. In this way the Fresnel design concept can be validated in an experiment. Reliable figures and data are essential to examine the very promising future of the technology and therefore confidence with customers and investors in the new technology. The technology should be ready for market by 2008 in large-scale.

Achieving success in partnership

MAN Ferrostaal is bringing to the project its many years of experience in the construction and operation of power plants of all types and thus reduces the risk of the development going wrong.
A further safeguard is provided by the experience, which the Solar Power Group has gained from another pilot plant - a 2500 m² large mirror farm, which has been continuously improved and developed over several years.
The Fraunhofer ISE, DLR and PSE researchers and engineers have been working for years on modelling the plant, evaluating the theoretical technology and regulating the reflectors for the linear Fresnel collector. Material designs, measuring techniques and simulation programmes are being used in the Almería demonstration plant, of which the development has been funded by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) in earlier projects, such as VDEMO-FRESNEL, Fresnel II, Fresquali and SOLDI. The pilot plant in Almería is thus the systematic application of knowledge and expertise which has already been gained.