ALTERNATIVE ENERGY SOURCES - THE CASE OF SOLAR ENERGY
FOR some time now, Zambia has relied upon conventional or traditional sources of energy such as hydropower for the generation of electricity and petroleum- based fuels for transportation purposes.
When we talk of alternative sources of energy, we are basically referring to those forms of energy which are not traditionally used. Biomass in form of wood fuel and charcoal has largely accounted for cooking and heating.
However, in this article, we shall talk about the use of alternative sources with a particular bias towards solar energy.
Solar energy is unique and important in many ways as an alternative to conventional forms of energy. Firstly, it is a renewable source whose reserves cannot be depleted. That is, so long as the sun will continue to illuminate the earth, solar energy shall be an option.
At the same, the world has come to the realisation that conventional sources of energy like coal are steadily diminishing. Due to the effects attributed to global warming and climate change, hydropower has become prone to adverse effects of droughts.
Secondly, the amount of radiation (solar energy) that is received on the earth’s surface is very significant. It is so enormous that all the primary sources of energy stored in the earth’s reserves put together, can only account for just about 20 days of sunshine.
Energy from the sun which is radiated in form of heat and light can be harnessed in a number of different ways. One way in which this can be done is by use of solar photovoltaic modules (commonly known as solar panels) to produce electricity.
Perhaps, this is the most common and popular method of utilising solar energy. Although this is not a technology currently implemented in Zambia, concentrating solar power (commonly known as “CSP”) technologies have been used in other countries. For example, it has been used in Morocco, Spain and the United States of America to produce electricity.
CSP technology uses collectors (reflecting mirrors or lenses) which concentrate a large area of sunlight, onto a small area. Electricity is generated when the concentrated light is converted to heat, which heats the water to produce steam. The steam is then fed into a turbine (just like in a coal power plant) to produce electrical energy.
Solar water heating is another cost effective way of producing hot water for domestic (homes) and commercial (hotels, lodges, schools, etc.) applications. Such technologies do not add to electricity bills but enable you to enjoy the hot water!
The money invested in the installation of solar water heaters is recovered through reduced electricity bills.
It is an established fact that the electrical geyser alongside electric stoves account for a significant part of the electricity bills incurred in most households or commercial undertakings.
In the recent past, conversations on use of electric vehicles are becoming increasingly common by the day. It is now official that the Zambian market has an electric vehicle. Solar energy will in this regard play a major role in modernising the transportation industry. In areas not connected to the national grid, electric vehicle charging stations may no doubt be powered by solar energy.
By and large, using solar energy for production of electricity and heating can contribute to reducing greenhouse gas emissions.
At present the contribution of solar energy to improving the electrification rate in Zambia is increasingly becoming noticeable.
For instance, there are now six solar mini-grids which are commercially operating in Samfya installed by the Rural Electrification Authority, in Lundazi operated by the National Technology Business Centre, Chirundu and Sioma run by Standard Microgrid Zambia Limited, Luangwa by Solera Power Vending Machine Limited, Chipata installed by the Ministry of Local Government, and Sinda by Muhanya Solar Limited. This is only a list of commercially operated solar mini-grids, but there are a lot more which are operated for own use to produce electricity. Other projects are still under construction and a number of investors are on the ground exploring the possibility of setting up more solar mini-grids countrywide. Clearly, the use of solar energy technology provides an effective alternative means of electrifying rural areas that are far from the national grid. Simultaneously, using a mix of solar energy technologies to provide electricity services in the rural areas can contribute to enhancing the efficient operation of the national grid. A mix of solar energy technologies in this case includes various configurations of solar home systems (SHSs). The advantage of SHSs is that they eliminate the need for redundant cables used in the distribution lines to evacuate power to the end use consumer. A simple illustration of an SHS may have a small solar panel mounted on the roof to light a bulb in a small
By and large, using solar energy for production of electricity and heating can contribute to reducing greenhouse gas emissions.
village house. Depending on the energy demand, SHSs can be scaled up to power additional loads, for example, refrigerators, fans, television sets and radios.
SHSs have now become popular for charging mobile phones in areas without access to electricity.
The National Energy Policy (NEP) of 2008 sets out the Government’s intention of ensuring that the energy sector’s latent potential to drive economic growth and reduce poverty is fully harnessed. Accordingly, solar mini-grids and SHSs present an opportunity for mitigating energy poverty, more especially in the rural areas.
Indeed, the role of solar energy technologies in fostering access to affordable, reliable, sustainable and modern energy for all in line with the Vision 2030 cannot be over emphasised. Electrification planning will focus on SHSs and solar mini-grids to achieve universal access to clean and sustainable energy. (To be continued)