Cheap Energy for Africa with Carbon Dioxide Reduction

For reliable renewable energy one needs costly batteries for steady supply and it seems unlikely we will be able to afford sufficient supplies of batteries in the near future. Here is the only solution I can see: 
1) Allow mines to install their own gas turbine power stations so mines can operate well and cheaply all the time
2) Encourage gas and oil companies to set up in South Africa, but legislate that they must distribute alkaline rock dust (from alkaline mine tailings, etc), to react with carbon dioxide and remove it from the atmosphere.
3) Also allow smelters to set up their own gas turbine power stations so that aluminium smelters, etc, can operate well all the time.
Africa and other regions need reliable power and it is unlikely that greenhouse gas concentrations will be reduced. The world could use gas and also alkaline rock to remove carbon dioxide in general from the air and the carbon dioxide created by burning the gas. We could cool Earth like this.
Taking CO2 out of the air: Here is some mathematics for all: Basalt has a density of about 3 tonnes per cubic metre.
A 1 mm thick layer of basalt spread over an area of 1 square km has a volume of (1/1000)x(1000)x(1000) = 1000 cubic metres.
Mass of 1 mm thick basalt layer on 1 square km = volumexdensity = (1000 cubic metres)x(3 tonnes per cubic metre) =3000 tonnes.
1 tonne of basalt can react with about 0.3 tonnes of CO2.
Therefore 3000 tones of basalt can react with about 3000x0.3 = 900 tonnes of CO2.
In a cubic metre of air in a polluted city there could be about 900 tonnes of CO2 in a cubic km.
Conclusion: A 1 mm thick layer of basalt could take out all the CO2 for a km above the basalt layer. Powdered basalt should be used to make the reaction thousands of times faster.

See https://insideclimatenews.org/news/20022018/global-warming-solutions-carbon-storage-farm-soil-crushed-volcanic-rock-research? and

https://arstechnica.com/science/2018/02/spreading-crushed-rock-on-farms-could-improve-soil-and-lower-co₂/ and

https://gulfnews.com/world/gulf/oman/oman-rocks-to-help-fight-global-warming-1.1810841 and

https://arctic-news.blogspot.com/2016/07/olivine-weathering-to-capture-co2-and-counter-climate-change.html?