The Problem with Solar Energy in Africa

Summary

The script explores the potential of harnessing solar energy from the Saharan Desert to power the world, highlighting the economic opportunities for impoverished nations. It discusses the Desertec initiative, challenges of electricity transmission, and the shift from concentrated solar power to cheaper photovoltaics. The video also touches on the environmental and social implications of large-scale solar projects in North Africa, advocating for local energy development and smart grid technology.

Takeaways

• 🌍 The Saharan Desert has enormous untapped solar energy potential, capable of generating enough electricity to power the entire world.
• 🔆 A single solar panel in Algeria can produce three times more electricity than the same panel in Germany due to the intense sunlight.
• 📈 Historically impoverished nations in North Africa could experience an economic boom by harnessing this solar energy.
• 🛠️ The challenge lies in transporting the generated electricity out of remote regions, with limited current interconnections to Europe.
• 💡 The Desertec initiative aimed to invest in solar energy infrastructure in North Africa and the Middle East, but has faced numerous setbacks.
• 🌐 High voltage transmission lines, both AC and DC, are necessary for long-distance energy transport, each with their own break-even points for cost-effectiveness.
• 🏭 Concentrated solar power (CSP) facilities, like the Noor complex in Morocco, use different technologies but face competition from cheaper photovoltaic solar panels.
• 💰 The cost of CSP has become less competitive compared to photovoltaic solar panels, affecting the feasibility of large-scale projects like Desertec.
• 🌞 The rise of cheap and efficient solar panels makes smaller, distributed solar farms more viable, reducing the need for massive investments in infrastructure.
• 💡 Water scarcity and the need for water in CSP facilities for cooling and mirror cleaning present additional challenges, especially in drought-prone areas.
• 🌿 For solar projects to succeed in North Africa, they must prioritize local needs and benefits, potentially combining energy generation with desalination and local irrigation.

Q & A

What is the potential of solar energy in the Saharan Desert and North Africa?

The Saharan Desert and North Africa have vast untapped solar energy resources. The solar energy that strikes the surface of this desert has the potential to power the entire world. A single solar panel in Algeria can generate three times more electricity than the same panel in Germany.

How much energy can a 1 square kilometre solar farm generate daily?

A solar farm of 1 square kilometre can generate 5 to 7 Gigawatt hours of energy each day, which is enough to satisfy nearly 100% of Europe’s energy needs.

What are the challenges in transporting electricity from North Africa to Europe?

Transporting electricity from North Africa to Europe is challenging due to limited interconnections. Currently, there are only two interconnections between Morocco and Spain, with a third expected before 2030. To power Europe, ignoring losses, would require 592 to 831 more of these 700 Megawatt interconnections.

What is the estimated cost of building additional interconnections to transport solar energy from North Africa to Europe?

Building additional interconnections to transport solar energy from North Africa to Europe is extremely expensive. The third interconnection between Morocco and Spain is estimated to cost 150 million dollars. Building 592 more connections would cost at least 8.9 billion dollars.

What was the Desertec initiative and what was its goal?

Desertec was a German-led initiative centered around a half trillion dollar investment fund that aimed to invest in generation and transmission infrastructure across North Africa and the Middle East. It aimed to utilize the region's solar energy to power Europe.

What are the differences between high voltage alternating current (AC) and high voltage direct current (DC) transmission?

High voltage alternating current (AC) transmission is suitable for shorter distances and loses more power per kilometre compared to high voltage direct current (DC). DC transmission is more efficient over longer distances, with about 3% loss per 1000 kilometres. The break-even point where DC becomes more cost-effective is around 500 to 800 kilometres.

How does concentrated solar power (CSP) differ from photovoltaic solar panels?

Concentrated solar power (CSP) uses systems like parabolic mirrors or tower systems to focus sunlight onto a single point, heating a working fluid that drives a turbine. It requires a lot of land and has a minimum viable operating temperature. Photovoltaic solar panels, on the other hand, convert sunlight directly into electricity and can be installed in various locations without the need for large tracts of land.

What are the operational challenges of concentrated solar power plants like Noor 1 and Noor 2 in Morocco?

Noor 1 and Noor 2, which use trough-based systems with parabolic mirrors, face challenges such as the need for a fossil fuel burning system to maintain minimum operating temperatures and to keep the oil system pumping. They also require a molten salt heat storage system to store heat for operational continuity.

Why has concentrated solar power become less competitive compared to photovoltaic solar panels?

Concentrated solar power has become less competitive due to the significant decrease in the cost of photovoltaic solar panels over the last decade. The cost per megawatt of CSP is higher than that of photovoltaics, making it difficult for CSP to compete in the market.

What are the environmental and social considerations for solar energy projects in North Africa?

Environmental and social considerations include the large land area required for CSP plants, the potential impact on local water resources due to the need for cooling and mirror cleaning, and the risk of foreign investment in politically volatile regions. It's also important to ensure that local communities benefit from these projects and that they are not exploited for the benefit of foreign countries.

What is the potential future for solar energy in Africa, especially in countries like Morocco?

Africa, particularly Morocco, has significant potential for solar energy. Morocco can lead by example by investing in its own energy needs and exporting excess to Europe. It has the advantage of proximity to Spain for short interconnections and consistent desert winds along its coast. The focus should be on local infrastructure to benefit local people first, moving away from being a net energy importer of fossil fuels to becoming an energy exporter.

Outlines

00:00

🌞 Saharan Solar Potential and Challenges

The Saharan Desert and North Africa are highlighted as vast untapped energy resources, with solar energy potential to power the world. Algeria's solar panels can generate three times more electricity than those in Germany. The script discusses the economic benefits for impoverished nations and the potential for solar farms to meet Europe's energy needs. However, challenges arise in transporting electricity from these remote regions, with only two interconnections between North Africa and Europe. The cost and complexity of expanding these interconnections are significant, with a third connection expected before 2030. The Desertec initiative, a German-led plan, aimed to invest in generation and transmission infrastructure but faced practical and financial obstacles.

05:04

🔌 Transmission and Generation in Desertec

The script delves into the technical aspects of the Desertec plan, focusing on transmission and generation. It explains the cost-effectiveness of high voltage direct current (HVDC) transmission over long distances and the break-even point where HVDC becomes more economical than high voltage alternating current (HVAC). Concentrated solar power (CSP) is contrasted with photovoltaic (PV) solar panels, with CSP requiring large land areas and having minimum operating temperatures. The Noor solar power plant in Morocco, the world's largest CSP facility, is described in detail, including its different sections and technologies. The challenges of CSP, such as maintenance issues and competition with cheaper PV solar panels, are also discussed.

10:04

🌡️ Concentrated Solar Power vs. Photovoltaics

This paragraph discusses the economic and practical challenges of concentrated solar power (CSP) compared to photovoltaic (PV) solar panels. CSP's land and temperature requirements make it less competitive in the current market, where PV panels have significantly reduced in cost. The Noor solar power plant in Morocco is used as an example, showing the high costs and maintenance issues associated with CSP. The script also touches on the risks of investing in volatile countries and the historical parallels of exploiting African resources for European benefit. Water scarcity and the need for technological improvements to reduce water consumption in CSP facilities are highlighted.

15:11

🌍 Africa's Solar Energy Future and Local Impact

The final paragraph shifts focus to the potential for Africa to benefit from its solar energy resources, emphasizing local infrastructure and the importance of prioritizing local needs. Morocco is highlighted as a leader in this effort, with its proximity to Spain and political stability making it a good candidate for energy export. The script also addresses the need for cross-border energy trading and the role of smart grids and algorithms in managing complex electricity grids. The potential for Africa's solar energy future is acknowledged, with a call for grassroots movements and technological improvements to support sustainable energy development.

Keywords

💡Saharan Desert

The Saharan Desert is the largest hot desert in the world, located in North Africa. It is known for its vast, arid landscape and intense sunlight. In the video, it is highlighted as a potential source of immense solar energy, capable of powering the entire world due to the high solar radiation it receives. The script mentions that a solar panel in Algeria within the Sahara could generate three times more electricity than the same panel in Germany.

💡Solar Energy

Solar energy is the radiant light and heat from the sun that is harnessed using various technologies, such as photovoltaics (solar panels) and concentrated solar power (CSP). The video discusses the Saharan Desert's potential for solar energy production, emphasizing its ability to provide significant amounts of electricity, which could be a boon for economically disadvantaged nations in the region.

💡Concentrated Solar Power (CSP)

Concentrated Solar Power is a type of solar energy generation that uses mirrors or lenses to focus a large area of sunlight onto a small area. The video describes CSP facilities, like the Noor complex in Morocco, which uses parabolic mirrors or a tower system to heat a synthetic oil or molten salt, thereby generating steam to drive turbines for electricity production.

💡Noor Solar Power Plant

The Noor Solar Power Plant, featured in the script, is the largest CSP plant in the world, located in Morocco. It consists of three sections utilizing different CSP technologies to generate a combined 510 MegaWatts of power. The plant exemplifies the potential of CSP but also faces challenges such as the need for fossil fuel backup and high water consumption for cooling.

💡Transmission Losses

Transmission losses refer to the decrease in electrical power capacity as it is transmitted over long distances due to resistance in the transmission lines. The video script discusses the challenges of transporting electricity from the Sahara to Europe, noting that significant interconnection infrastructure would be required to minimize these losses.

💡High Voltage Direct Current (HVDC)

High Voltage Direct Current is a type of electrical transmission that uses direct current for the transmission of electrical power over long distances or across large areas. The video explains that HVDC is more cost-effective and has lower power losses compared to AC for distances beyond the break-even point of 500 to 800 kilometers.

💡Desertec Initiative

The Desertec Initiative was a project aimed at developing a large-scale solar power production facility across North Africa and the Middle East to supply Europe with renewable energy. The video outlines the initiative's goals, challenges, and eventual dissolution due to the falling costs of photovoltaic solar panels and geopolitical concerns.

💡Levelized Cost of Electricity (LCOE)

The Levelized Cost of Electricity is a measure of the average cost of producing electricity from a specific energy source over its lifetime, taking into account construction, operation, and maintenance costs. The script mentions LCOE in the context of comparing the costs of CSP and photovoltaic solar power, noting that CSP struggles to compete in the current market.

💡Smart Grid

A smart grid is an electrical grid that uses advanced digital technology to monitor and manage the transport of electricity from all generation sources to meet the varying demands of end users. The video suggests that the complexity of managing large-scale electricity grids, like those proposed for the Desertec project, requires smart grid technology to optimize operations.

💡Molten Salt Storage

Molten salt storage is a type of thermal energy storage used in CSP systems to store the sun's thermal energy as heat in molten salts. The video describes how the Noor plant uses molten salt to store energy, allowing the plant to continue generating electricity even when the sun is not shining, but also points out the challenges of maintaining the system's temperature.

💡Water Scarcity

Water scarcity refers to the lack of sufficient water to meet the needs of humans, animals, and plants in a region. The script discusses the water consumption of CSP plants, such as the Noor facility, which uses significant amounts of water for cooling and mirror cleaning, raising concerns about the sustainability of large-scale solar projects in water-stressed regions like North Africa.

Highlights

The Saharan Desert and North Africa have the potential to generate solar energy sufficient to power the entire world.

A single solar panel in Algeria can generate three times more electricity than the same panel in Germany.

A 1 square kilometre solar farm in the Sahara can generate 5-7 Gigawatt hours of energy daily, enough for nearly all of Europe's energy needs.

Plans to harness Saharan solar energy have faced numerous challenges and have not yet been successful.

Transporting electricity from North Africa to Europe is a major challenge due to limited interconnections.

The Desertec initiative aimed to invest in solar power generation and transmission infrastructure across North Africa and the Middle East.

High voltage direct current (HVDC) transmission is more cost-effective for long distances, but requires expensive transformers and converters.

Concentrated solar power (CSP) facilities, like the Noor plant in Morocco, use mirrors to focus sunlight on a central point to generate electricity.

The Noor 3 CSP plant uses a tower system, eliminating the need for oil and pumps, and directly heats molten salt for energy storage.

The cost of concentrated solar power has become less competitive compared to photovoltaic solar panels due to the latter's significant price drop.

The Desertec initiative faced skepticism due to the potential for exploitation and the historical parallels with colonial resource extraction.

Morocco is well-positioned to lead in solar energy due to its proximity to Europe, political stability, and abundant solar and wind resources.

The water consumption of CSP plants is a concern, especially in water-scarce regions like Morocco.

The future of solar energy in Africa should focus on local benefits and grassroots movements rather than large-scale foreign investments.

Smart grids and algorithm-based management are becoming increasingly important in the operation and optimization of electricity grids.

Learning about algorithms and coding is an invaluable skill for understanding and participating in the modern energy sector.

Transcripts

The Saharan Desert, and North Africa at large, is one of the world’s greatest untapped

energy resources. The solar energy that strikes the surface of this desert has the potential

to power the entire world, a single solar panel placed here, in Algeria, is capable

of generating 3 times more electricity than the same panel, placed in Germany. [1]

What was once a geographic disadvantage, the scorching sun of these desolate lands could

now provide an economic boom for these historically impoverished nations.

A panel in a solar farm located here, 1 square metre in size, would on average generate 5

to 7 kWhs of energy each day. Increase that to 1 square kilometre and we are generating

5 - 7 Gigawatt hours of energy each day. Increase that to 1000 square kilometres and we are

generating 5-7 Terawatt hours of energy each day.

Enough to satisfy nearly 100% of Europe’s energy needs. [2] Multiply that by 10, and

we are generating 50-70 Terawatt hours a day. Enough to power the entire world. [3]

This is an impressive and often repeated statistic. [4] Napkin calculations that draw a drastic

new vision of the world. A solar powered Eutopia. Plans have even been drawn up to transform

the simple mathematics into a reality, but reality has a way of interfering with futuristic

pie in the sky calculations like this. Every plan to turn this dream into a reality has

failed. In this episode we are going to learn why.

Transporting electricity out of these remote regions is the first challenge. Currently

there are only two interconnections connecting North Africa to Europe. Both are located between

Morocco and Spain.

Two 700 Megawatt interconnections. One completed in 1998 and the second completed in 2006.

With a third connection expected to be completed sometime before 2030, for a total of 2100

Megawatts. [5]

If we wanted to transport enough electricity to power Europe, ignoring transport losses

and storage issues, we would need 592 to 831 more of these 700 Megawatt interconnections.

These aren’t just simple cables that we lay between countries. They are incredibly

complicated and expensive pieces of infrastructure. The third interconnection joining Morocco’s

and Spain’s grids is estimated to cost 150 million dollars. An enormous investment that

will see both countries footing half the bill.

592 more of these connections would cost, at an absolute minimum, 8.9 billion dollars,

and that number was found by simply multiplying 150 million by 592, but these connections

are the shortest route to Europe from North Africa. They are going to be the cheapest

to build. To build a truly interconnected grid we are going to need even longer interconnections,

connecting Tunisia to Sicily, Algeria to Sardinia and onwards to Northern Italy, Libya to Crete

and onwards to Greece and Turkey and to the rest of the Middle East Network, all the while,

building enough internal interconnections in Europe to facilitate the passing of the

solar parsal northwards, while Wind is traded south.

This plan will take billions to complete. Yet, even with these issues, European leaders

have drawn up plans to connect North Africa and the Middle East to Europe, they believe

the costs can be recovered.

Desertec is, or perhaps more appropriately was, a German led initiative centred around

a half trillion dollar investment fund [6] that would invest in generation and transmission

infrastructure across North Africa and the Middle East.

55 Billion was allocated to increasing transmission capabilities across the Mediterranean. [6]

This investment would go into both high voltage alternating current transmission over shorter

gaps, like those from Morocco to Spain and high voltage direct current over longer distances.

There is a critical distance where high voltage alternating current transmission does not

make sense.

If we plot transmission losses per kilometre for AC and DC transmission, it would look

something like this, with DC losing less power per kilometre. [7] However, in order to convert

our regional AC grid power to DC for these long distance transmission cables, we need

expensive transformers and converters. If we instead plot cost versus distance, counting

in this infrastructure. It would look something like this, and we can see that the DC and

AC lines cross each other around the 500 to 800 kilometre mark. [8].

This is the break even point where DC becomes more cost effective. So, lines connecting

Morocco directly to Spain, which spans only 28 kilometres, don’t make sense for high

voltage direct current. While longer lines connecting Tunisia to Italy will likely be

high voltage direct current lines.

Transmission losses for High Voltage DC is about 3% per 1000 kilometres and Germany’s

capital is only 1,800 kilometres from Tunisia. [9] Transmitting power, with this much investment

money, is perfectly feasible. The technologies exist. So let’s move into the generation

part of the Desertec plan.

Desertec was formulated with concentrated solar power in mind, which works very differently

to photovoltaic solar panels. Concentrated solar power facilities would be spread out

along the borders of the Sahara and Arabian Deserts.

One such facility already exists in Morocco and it’s the largest concentrated solar

power plant in the world.

It is massive, with 3 separate sections, Noor 1, 2 and 3, each using slightly different

variations of concentrated solar power, combining to provide the 510 MegaWatts.

Noor 1 and 2 are both trough based systems that use parabolic mirrors with a tube located

in the mirror's focal point. The tube contains a synthetic oil which collects the heat from

the 500,000 parabolic mirrors spread out over 308000 square metres. This oil becomes extremely

hot, as high as 400 degrees celsius, which allows it to boil water in a heat exchanger

to drive a steam turbine, which provides electricity for the grid. The 400 degree oil is also hot

enough to melt salt in a molten salt heat storage system. The molten salt heat storage

system of Noor 1 can store enough heat to keep the plant operational for 3 hours while

Noor 2 has enough storage for 7 hours. However this salt solidifies at 110 degrees and if

that happens, the plant won’t work in the morning, so Noor 1 and 2 need a fossil fuel

burning system to keep all the working fluids of the system at minimum operating temperatures

over night and to keep the oil system pumping. This fossil fuel burning system can also keep

the plant operation as a reliable baseline energy source. Removing the need for separate

natural gas peaker plants. [10]

Noor 3 does not use these parabolic mirrors and instead uses a tower system. It’s this

striking circular facility to the north. It looks less like an industrial facility and

more like a new age burning man art installation. This design allows Noor 3 to rid itself of

the oil, plumbing and pumps of Noor 1 and 2, and instead it uses mirrors arranged in

concentric circles around a central tower. The mirrors are then controlled to focus light

on a single point on the tower, which directly heats the molten salt, which is the working

fluid instead of an oil based system. The solar concentration here is much higher and

in turn, the temperatures attained are much higher. With the water being heated to 550

degrees.

This allows the tower based system to use more efficient steam turbines and using molten

salt as the working fluid removes the need for a oil to molten salt heat exchanger in

the heat storage system [11] Noor III is the world’s only operating tower based concentrated

solar power system with molten salt storage, after 2019’s shutdown of Nevada’s Crescent

Dunes plant.

The Crescent Dunes plant ceased operation in 2019, after only 4 years of operation.

[12] NV Energy broke it’s purchasing contract with the plant after it failed to meet performance

requirements. Being marred by maintenance issues, including an 8 month shutdown due

to a leak in the molten salt tank. Even when fully operational [13], the plant's electricity

cost 135 dollars per megawatt hour while a nearby photovoltaic plant was managing 30

dollars per megawatt.[14] And here lies the crux of the issue.

Concentrated solar power cost per megawatt was extremely competitive with photovoltaics

in 2009, but in the last decade photovoltaics have become obscenely cheap. Concentrated

solar power simply cannot compete in a market like this, and the same can be seen for Noor

1, 2 and 3.

However, they are currently being measured on a metric called levelized cost of electricity,

which is an average of the costs to generate electricity over the entire life of the plant.

However, this does not factor in the cost of storage for photovoltaics, which is often

just an inherent benefit of concentrated solar thermal power. So going forward, the industry

should be using a combined cost of storage and cost of electricity metric. Yet…. (this

bit needed to lead into next paragraph)

The most recent addition to this solar farm is Noor 4, a solar panel farm contributing

73 Megawatts. With the rise of cheap solar panels Desertec, contrary to what you may

expect, was doomed for failure.

Concentrated solar thermal power, by nature, needs a lot of land. The plant has a minimum

viable operating temperature, and to achieve that we need enough mirrors to reflect that

light. Solar panels do not have this problem. Solar panels can be fitted on top of homes,

over car parks or even in farmers fields to help shade plants that need shade. We don’t

need massive plots of land to make them work.

And because they are so cheap, it’s perfectly feasible to build smaller solar farms in Germany,

and avoid those transmission losses, and not incur the massive financial risk of investing

billions into a country that is not your own. That’s particularly important because a

lot of investors are very hesitant to put money into these often volatile countries.

We need to look no further than the 2013 attack on a BP natural gas plant in Algeria, to see

why this would be considered a risky investment in many parts of North Africa.

“It’s a vital economic resource for Algeria, yet it sits isolated in the midst of a vast

desert. That’s a transit root for Al Qaeda in North Africa, no wonder it was so difficult

to defend and such a tempting target for the militants.”

This is exactly why Germany is instead investing in its own domestic photovoltaic generation,

and in 2020 solar power accounted for 10% of Germany’s power generation. [15]

This idea of European countries drawing natural resources from Africa to benefit its own economy

has some undeniable problematic historic parallels. Any foreign investment like this is going

to come with some guarantees of supply for Europe. Beyond the difficulties of organizing

cross border cooperation like this, that’s not going to go down well when the country

hosting these plants needs that power for their own grid. To grow their economy or simply

stabilize their own grid for current needs. It becomes even more problematic when we consider

the amount of water these facilities need for cooling, for the steam turbine and to

keep the mirrors clean.

This facility in Morocco uses 2.5 to 3 billion litres of water every year, taking water from

a dam 12 kilometres away. [16]

Morocco is already susceptible to droughts, so scaling these water demands up, just to

feed Europe’s power needs, while taking water away from the farms that feed Moroccan

citizens, is even more problematic. To truly scale this power generation, some technological

improvement that reduces the consumption of water would be needed, or just pair the facilities

with desalination plants and use the extra water, if any, to irrigate local farms to

boost local economies even more.

For this dream of turning the Earth’s barren deserts into energy generation centres to

come true, it has to be a grassroots movement. Not some new age imperialism megaproject that

comes with a whole host of guarantees in exchange for the nearly half trillion dollar investment.

North Africa is one of the hardest hit regions in the world by climate change, with desertification

and water scarcity becoming a serious issue. This plan, despite its surface level good

intentions, sought to exploit these countries that have suffered most as a result of Western

Industrialisation. We don’t need to look for proof that this was their intention. The

moment the technology developed to allow European countries to provide their renewable power

needs within their own borders, the plan disintegrated. This plan was never about helping African

nations.

But, the idea isn’t dead in the water. These countries do have the natural resources to

benefit from solar energy. Morocco is in the best position to lead by example.

It’s proximity to Spain allows relatively short interconnections to the European grid.

It’s government is relatively stable compared it’s North African neighbours with a political

stability index of minus 0.33. Algeria, Tunisia, Libya and Egypt are all much lower and while

Morocco has abundant solar resources, it also benefits from consistent desert winds along

its coast.

Morocco has the potential to invest in its own energy needs, while exporting excess to

Europe. Leading by example. Slowly shifting away from being a net energy importer of fossil

fuels, and becoming an energy exporter. Local infrastructure to benefit local people first.

An African nation using its resources to benefit itself first and foremost. The potential for

Africa’s solar energy future is undeniably. The technologies to facilitate cross border

energy trading exist, and investments are happening to increase capacity for trade with

this 3rd interconnector between Morocco and Spain, funded equally by both sides, ensuring

a level playing field.

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