PacB Group // Could Solar Power be the Key to Sustainable Energy?

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Could Solar Power be the Key to Sustainable Energy?

The sun is almost 150 million kilometres from our world yet, even from this vast distance, the energy it radiates is sufficient to illuminate earth’s surface and to sustain all of its animal and plant life. Furthermore, scientists suggest that it could well continue to radiate its energy for several billion years to come. Since man first learned how to direct that solar power by means of a lens in order to spark a fire, there have been some important advances as a result of efforts by humankind to leverage this near-infinite source of energy for more useful purposes.

Following the industrial revolution, when steam finally gave way to electricity, the possibilities for this new man-made energy source must have seemed almost unlimited. It could be used to create both warmth and light, even at night, and thus it appeared to outperform the most basic functions of sunlight. Now, some two centuries later, humans are recognising that solar power might be able to provide earth’s vast population with all of the electricity it could possibly consume. So why is this so significant?

The vast majority of electricity has always been generated by consuming natural resources, such as coal and gas with only relatively small quantities produced by hydroelectric schemes. The result has been twofold. Those natural resources are slowly becoming depleted, and in the process, their combustion has led to dangerous levels of atmospheric pollution that now threaten all life on earth. By contrast, solar power offers what, to all intents and purposes, can reasonably be thought of as an inexhaustible energy supply and one that consumes no scarce resources and produces no toxic pollutants. So, how does it work?

In fact, there are two ways in which we have learned to exploit the free energy in the sun’s rays. Its warmth is the result of infra-red radiation, which can be focused in order to heat water for domestic hot water systems or even to boil it in order to drive a turbine and thus generate electricity. A more direct use of solar power makes use of a phenomenon known as the photovoltaic effect. In this case, collisions with photons of light in the UV region act to displace the excess electrons from a specially treated semiconductor. These are attracted to a second semiconductor layer that is electron-deficient, producing a flow of direct electric current in the process.

One photovoltaic cell is able to generate only a small voltage, and so, multiple cells must be connected to form a panel of which several may be required to meet the needs of a given installation. As a result, a solar power installation can be quite costly. However, there have been a number of advances that promise to make this technology both simpler and cheaper. These include photovoltaic glass and some very promising research relating to the development of a photovoltaic paint that could be applied to almost any surface.

However, the existing technology has proved to be highly scalable and a number of utility companies, including Eskom have been investing in huge arrays with the capacity to generate solar power on a commercial scale. Already, the energy of the sun’s rays is being harnessed and the product of wind farms, hydroelectric schemes, and tidal barrages are coming online in countries across the globe. When leveraged together, the prospect of a truly sustainable energy solution finally appears to be within our reach.

The only outstanding problem awaiting a viable solution is that of developing the means to eliminate the carbon footprint arising from the manufacture and disposal of the panels that remain necessary to harness the limitless reserve of solar power at our disposal. This challenge too will be overcome and, when it is, you can be sure that PacB Group will lead the deployment of this ultimate power solution in South Africa.