Extrusions for the structural components of solar panels, the frame extrusions for the solar cell modules, precision piping and rolled products in the solar panels as well as the façade and construction system with integrated solar cell technology are examples of products in the field of solar energy. Hydro is also involved in joint ventures for the development of materials and technology for the production of solar cells.

The use of solar energy started on a small scale during the seventies but it is only during the past decade that developments have gained pace. This is a result of the ambition to increase the use of sources of renewable energy to reduce the impacts on the environment and the climate. Even so the contribution made by solar energy is modest, only 0.04% of the world’s total energy consumption and 0.15% of electricity produced (2008). Developments are however moving rapidly forward with lower costs for production units, increased efficiency and improved storage techniques.

A rapidly growing market
Every year Hydro delivers large volumes of extrusions to the many companies around the world engaged in the rapidly growing solar energy market. There is rapid expansion in the USA, Europe and Asia. In Europe, Germany in particular has a large and active market for solar energy. In Norway and Sweden there are leading players in the development of modern solar energy technology. Hydro Aluminium Profiler manufactures extrusions for the solar energy sector which through our customers and partners are used around the world. The market for solar energy products is growing steadily and forms an important growth market for Hydro. Aluminium is eminently suitable as a construction material here because of its green profile and unique characteristics. With Hydro’s long experience and skills in metallurgy, production and product development, the company, together with its customers, can make a major contribution to the development of new, improved and more efficient systems for the production of solar energy.

One of the world’s largest solar thermal power stations, Nevada Solar 1 in Nevada. It started up in June 2007, covers an area of over 100 hectares, has a capacity of 64 MW with an annual production of 130,000 MW and consists of over 9,000 aluminium stands that hold 180,000 mirrors.

Extrusions in framework systems
In enormous solar thermal power stations, the sun’s rays are concentrated using concave mirrors either on liquid-filled pipes at the focus of the mirror or by the mirrors reflecting the rays to a receiver located on a tower. The sun’s rays heat up the water which drives a steam turbine that produces electricity through a generator. The mobile mirrors which follow the sun’s path are mounted on frameworks that have traditionally been made of steel. In recent years, Hydro has delivered aluminium extrusions for framework systems which have, the advantage of halving the number of parts, are 30% lighter, take less time to assemble and reduce the maintenance required. Hydro has now delivered such framework systems to three solar thermal power stations in Spain and two in America with a combined capacity of 300 MW.

Built-in solar energy
For the structural work, we have fused our efforts in the way of using solar technology as naturally and securely as traditional constructive elements, thanks to our experience in aluminium systems.

Aluminium curtain wall façade with integrated thermal solar panels was awarded a prize at Intersolar 2010 and is nominated for the EAA innovation award.

Consequently Hydro Building Systems has developed products for the integration of solar modules in the company’s system, the so called BIPV – Building Integrated PhotoVoltaic system, through Curtain Wall Façades, Skylight System or Sun  Protection with its Wicona and Technal brands. The first catalogue products available are the sunshading systems WICSolaire PV and Suneal PV, using traditional crystalline cells encapsulated in glass. Together with Ascent Solar, one of the companies in which Hydro has shares, HBS is developing BIPV with thin-film solar modules, where the cells - metallic copper, indium, gallium and selenium are coated onto a flexible plastic foil. The result is lightweight solar modules that can be applied to curved surfaces. This makes this solution especially suitable for buildings.
Recently Hydro Building Systems has also proposed together with the Ritter group and other research partners, a prize winning system for thermal solar energy with mirrors and vacuum tube technology that is built into the company’s aluminium façades, the so-called WICTEC CPC. Project studies for architects and software simulations on building energy performance are part of the services provided by HBS to support customers in this new and promising solar integration.

Precision solar energy
For thermal solar panels, Hydro’s business sector Precision Tubing makes a series of products perfectly adapted for use as heat absorbers and for the distribution of liquid media. The products include precision drawn pipes, manifolds, flexible pipes and several types of multi-hole extrusions.

Rolled energy
Within the rolled products business sector Hydro has developed a series of products aimed at the growing solar energy market that are based on high lustre, surface treated sheet and strip aluminium for reflectors. These are used in both solar panel and thermal systems such as HyGloss Aluminium, HyBridAl, HySelect or Hydro Substrates.

Development projects
Together with its partners, Hydro is developing new techniques, products and manufacturing methods for applications within the solar energy sector. Current projects worth noting are the development of super clean silicon for solar cell production (Hycore) and super thin and flexible solar cell modules (AscentSolar), and the production of monocrystalline silicon wafers for solar cells (NorSun).

Facts solar energy
Solar energy is the conversion of sunlight into electricity. This can be done directly using solar cells (PhotoVoltaic) or indirectly by concentrating sunlight through the heating of a fluid media for direct heating or to drive a generator in a so-called solar thermal power station. The advantage is obvious – an unlimited supply of free solar energy. The disadvantages are expensive plants with solar panels, ineffective systems for storage on cloudy days and night-time darkness. The technology is however continually being developed with improvements in both efficiency and storage capacity. At present thermal solar energy is the most effective, primarily because of the high cost of solar cell technology. The best commercially available solar cells available today have an efficiency level of 15% to 20%. The efficiency today of conventional solar thermal power stations that use concentrated solar power (CSP) is about 20%. The world’s first modern commercial solar thermal power station opened in 2005 in Seville, Spain. Several have been built since where Hydro has played an active role as supplier and partner including one of the world’s largest; Nevada Solar 1. However, the advantages of solar cell technology are obvious; the direct conversion to electricity without the need for fluid media, piping and long lines of distribution and the ability to fit the panels directly wherever they are needed. At the same time the development of solar cell technology is advancing rapidly; its cost is one twentieth of what it was three decades ago and its efficiency has tripled! Today, Hydro is involved in a number of projects for the development and improvement of solar technology.