Thursday, January 28, 2021

Power to the People

 Africa is huge, much larger than the standard Mercator map projection indicates. Africa is the size of the US, Europe, China, India and Japan combined. The African Island of Madagascar is larger than the UK. South Africa alone is the size of the whole of Western Europe. Africa is sparsely populated in comparison to other countries. 

According to the International Energy Agency (IEA), some 580 million of the 1.3 billion people living in Africa are without electricity.

 Many African countries rely to a very large extent on hydropower. But much African hydro is very problematic because of unpredictable rainfall patterns, but also because dams are very wide and shallow, in comparison to dams in Nordic countries for example. So it is very challenging to maintain the pressure-head and water volume required for hydroelectricity.

Many Africans live in remote, thinly populated areas where the expansion of the central energy grid is not economically viable. Major infrastructure development of electrification such as very high-voltage power lines of over 1,000km in length are unheard of in Europe.Such power lines also traverse one of the highest lightning incidence areas on the planet. 

 Daniel Busche, leader of the energy access programme of the German development authority GIZ suggested that, "Decentralised approaches would be better for that."

While energy from a gas or coal power station can only be accessed through a central line, solar energy generated by the sun is accessible to everyone, everywhere. Decentralised approaches to energy supply are a chance to skip building large, national energy grids in order to provide all people more efficient and possibly more democratic access to energy.

But "The continent with the richest solar resources in the world has installed only 5 gigawatts (GW) of solar (photovoltaics), less than 1% of the global total," according to an IEA report.

One of the more promising solutions is flexible mini grids, which produce energy via solar panels and can span from a few houses to entire villages. But the investment costs are high, and the profitability often low, Busche says. There are few firms willing to operate such grids.

Home systems are quicker and easier than mini grids in providing solar energy. They are small modules that can be installed on rooftops. Depending on their size, the systems can charge a phone, power a television set or provide energy for the whole house. Small panels, which produce 50 to 200 watts of energy can, for instance, operate a shop - such as a phone charging station, hair salon or supermarket.

Another media report suggests nuclear power as another option. In South Africa the decision is to adopt nuclear power, a source of sustainable clean energy. At least seven African countries have signed agreements with Russian nuclear company Rosatom to develop nuclear capability.  Small Modular Reactors (SMRs) are currently being developed which are ideal for deployment in virtually any location. Large conventional nuclear can be 3,000MW in size whereas an SMR is only about 100MW in output. The term ‘modular’ refers to small sub-assemblies which can be fabricated in factories and then integrated on-site.  Nuclear and renewable energy complement each other very well. SMRs can vary power output at the will of the system operator. Renewable energy sources such as wind and solar depend on the variable weather. If a cloud is cast over a solar plant, nuclear power can be ramped up to replace the reduced output. SMR systems can be sized for the needs of any country, and be placed close to large load centres thereby reducing the need for expensive transmission networks.

Why do millions of people in Africa not have electricity? | The Star

Nuclear power: A sensible and sustainable option for Africa - Power Engineering International

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