opinion: why sa can't make a massive shift to renewables - yet - power storage devices

Hatmute Winkler has had a heated debate in South Africa on the extent to which renewable energy should replace coal, especially given the threat of climate change.
China's electricity supply is now heavily dependent on coal.
While it is clear that coal is 100% renewable energy and will not disappear soon
From now on, driving power generation scenarios are feasible and desirable in a generation.
A major shift in global energy is redefining the way power is generated and powered.
In the past, electricity production was mainly controlled by large, often polluting power giants.
Factory distributed through large wires.
But now the trend is small.
Units of scale mainly supply localized power networks.
These changes are driven by powerful factors.
First, the serious threat of climate change is largely caused by emissions from coal-fired power plants.
Another factor is that nuclear energy, while clean, is less economically competitive.
Nuclear power plants already under construction are always plagued by delays and cost overruns and allegations of misconduct in the procurement process.
Another major driver is the development and promotion of renewable energy technologies.
It is the cheapest option to make wind and solar photovoltaic power generation possible by significantly reducing costs.
There is a lot to do in South Africa with regards to renewable energy-good sunshine and coastline help with wind power.
But many factors have hindered its ability to get rid of coal altogether.
The biggest reason is that wind and solar energy are intermittent, and new technologies that can be stored cheaply and efficiently have not yet been developed.
South Africa's power landscape South Africa's latest power plan, the Power Integrated Resource Plan, is under discussion.
The final plan covering the period ended 2030 is expected to be approved by the end of this year.
The current draft has basically been positively evaluated.
It expects growth in electricity demand to be lower than previously expected.
It also excludes any new nuclear developments over the next 12 years.
The new draft proposes the development of a strategy that envisages a substantial increase in renewable energy generation capacity.
This will be short time with intermittent
When wind and solar energy cannot meet the demand for electricity, generate electricity from natural gas.
This is the cheapest option.
The reason for preferring natural gas rather than nuclear power is that while natural gas is the most expensive fuel for power generation, it is much cheaper to build a gas station.
They can also be turned on and off faster than competing fuels
Basic technologies such as coal and nuclear power.
The proposed scenario project for the best scenario project adds the following power generation capacity during the period from 2019 to 2030: 9. 5GW wind, 6. 8GW solar, 8. 1GW gas, 6. 7GW coal and 2. 5GW hydropower.
This includes projects that have been approved or are under construction, in particular the remaining units of Medupi and Kusile coal plants.
These figures reflect the idea of maximum power generation capacity-for example, what will be generated by wind farms when wind blows, and what will be produced by solar equipment in sunny conditions.
In the case of gas, the purpose is to treat this capacity as a backup.
These power supplies run only if other power supplies do not meet the power needs.
On average, South Africa's energy structure will remain coal-based in 2030.
The electricity produced by energy is subdivided into 64% coal, 13% wind power, 8% solar energy, 4% nuclear energy, 3% hydropower and 1% natural gas.
The proposal for the plan covers only 2019-2030.
But it also provides a draft model for the energy mix as far as 2050.
It is predicted that in 2050, 42% of the electricity will come from wind, 20% from solar energy, 17% from coal, 11% from natural gas and no nuclear energy.
This means that, according to most of the current energy planning models, 100% renewable electricity in South Africa has not yet emerged.
Is it possible to generate 100% of renewable energy?
Several countries have taken almost all of their electricity from renewable sources.
They include Colombia, Iceland, Norway and Paraguay.
Their population is much smaller than that of South Africa, and they enjoy a lot of water and electricity.
As far as South Africa is concerned, it's a water-scarce country.
But there is a lot to do in South Africa.
With plenty of sunshine, the coastline and cliffs provide a great place for wind farms.
So how can South Africa achieve a mix of 100% renewable energy?
It cannot rely on natural gas, which is not renewable energy.
It can't count on water and electricity, even if it's super
Projects are planned along the Congo River.
There are also interesting options, such as biofuels and ocean-stream energy.
However, they have not yet been properly established.
That leaves wind and solar energy.
The fatal weakness of both is that the search for a fully renewable energy supply depends on the ability to store electricity for a long time.
Great progress has been made in increasing storage capacity and commercializing newly developed technologies. But cheap long-
The word "electric storage" is still largely out of reach or impractical.
Ultimately, the nature and cost of technological advances-both in storage and one of a variety of power generation technologies-will determine whether South Africa can move its energy portfolio significantly to renewable energy. -
Hatmuth winklis is a professor of physics at the University of Johannesburg.
This article was re-published from the conversation based on the creative sharing authorization.
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