/ 7 September 2010

Sun of a gun technology

Sun Of A Gun Technology

The number of pilot projects for renewable energy is growing almost by the day. One of the latest is a concentrated photovoltaic (CPV) solar energy project at the Aquila Game Reserve near Touwsrivier in the Western Cape.

CPV supplier Concentrix, which has built the pilot project, is looking to establish CPV as a real option for the country’s future power needs. Holger Janke, Concentrix’s chief financial officer, says that the intention of the company is to establish the pilot project, which would spearhead a larger scale project in the area. There are three types of solar power technology, all of which are vying to be the technology of choice when it comes to providing renewable energy.

The most common of these is conventional photovoltaic cells. These are the solar panels that you will see installed in residential areas and are the only form of solar power that can be used to power individual homes.

The second form of solar power is concentrated solar energy, where mirrors are used to reflect the sun onto a central boiler and the steam generated from this heat is used to turn a turbine and generate electricity. The third form of solar power is concentrated photovoltaic cells. These cells use a much smaller but more efficient photovoltaic cell than traditional photovoltaic systems.

Janke says that in the system at the pilot site the actual PV cell is about the size of a nail head and each component has a 6cm by 6cm concentrator that focuses the sunlight on to the cell, where it is converted to electricity. Each unit is mounted into a set of 90 modules and each set should generate about 6kW of electricity.

The units also track the sun, which ensures that they are able to generate electricity from sunrise to sunset. He says that this is one of the more effective ways of generating electricity from the sun. It has an efficiency level of 25% in real world conditions as opposed to traditional PV systems that operate at about the 10% to 11% level.

Janke says that the 60kW generated by the pilot project should be enough to satisfy the daylight needs of the game farm at present but, because there is no storage associated with the project, it would not enable the farm to run independently of the national grid.

He says that, with the renewable energy feed-in tariffs (Refit) having been published, the industry is waiting for Eskom to start entering into power purchasing agreements (PPA). This is the single biggest stumbling block in getting the larger project off the ground.

The company is conducting an environmental impact study for a 50MW system and is also negotiating with potential partners to finance the construction. Once these are in place and the PPA has been signed, he says it will take about six months for the first electricity to come on line, with the full 50MW being available in about 29 months.

Janke says that the company selected Touwsrivier as a site for the project because it was close to Eskom transmission lines and there was a need for economic upliftment in the area. The Refit for PV generated electricity is R3.94/kW h, which already gives the CPV technology an advantage over the concentrated solar power, which has a Refit of R2.15/kW h, according to Janke.

If the efficiencies of CPV come to the fore the technology could provide an attractive opportunity for investors wanting to get into the renewable energy market. He says that for the country to get the full benefit of the growth in renewable energy there would need to be enough demand to make setting up local manufacturing facilities feasible. Otherwise all the components would need to be imported, increasing the cost of the technology.

Solar power has always been touted as a strong contender for the country’s future energy requirements and Janke says that, properly implemented, it could provide 10% of the country’s capacity in the future.

Supplying answers to the questions
The demand for electricity and water — two resources essential for a growing world — is expected to increase dramatically over the next 20 years. But what can we do in our country, companies, communities and homes to better use and manage these ever scarce resources?

These and other questions about sustainability were discussed recently at a stakeholder engagement session at ABB South Africa’s head office in Johannesburg. These debates have been held voluntarily by the power and automation technology leader during the past four years to engage stakeholders on key issues such as energy efficiency, renewable energy and skills development.

A clear call has been made by stakeholders, including customers, employee representatives, suppliers, universities, municipalities and business and community-based organisations, for technology companies such as ABB to assist in creating more awareness about the technology available for the efficient use and conservation of energy and water.

Carlos Pone, the ABB South Africa chief executive officer, said that the ABB Group increased investment in research and development by 7% in 2008 and a further 5% in 2009, despite the recession. A major part of the investment went on energy-efficient technologies.

He said with the increasing electricity demand and the pressure of carbon emissions on the environment, energy efficiency was vital. It was also important to develop skills in the industry with customers, suppliers and tertiary institutions, Pone said. “We are developing engineers as well as artisans. We need to make artisan professions more attractive for young people.”