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The Problem with Solar Energy in Africa - YouTube
Channel: Real Engineering
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the saharan desert and north africa at
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large is one of the world's greatest
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untapped energy resources the solar
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energy that strikes the surface of this
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desert has the potential to power the
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entire world a single solar panel placed
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here in algeria is capable of generating
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three times more electricity than the
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same panel placed in germany what was
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once a geographic disadvantage the
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scorching sun of these desolate lands
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could now provide an economic boom for
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these historically impoverished nations
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a panel in a solar farm located here one
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square meter in size would on average
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generate five to seven kilowatt hours of
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energy each day increase that to one
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square kilometer and we are generating
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five to seven gigawatt hours of energy
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each day increase that to one thousand
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square kilometers and we are generating
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five to seven terawatt hours of energy
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each day enough to satisfy nearly 100
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of europe's energy needs
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multiply that by 10 and we are
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generating 50 to 70 terawatt hours a day
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enough to power the entire world
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this is an impressive and often repeated
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statistic
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napkin calculations that draw a drastic
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new vision of the world a solar powered
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utopia plans have even been drawn up to
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transform the simple mathematics into a
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reality but reality has a way of
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interfering with futuristic pie in the
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sky calculations like this
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every plan to turn this dream into
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reality has failed in this episode we
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are going to learn why
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transporting electricity out of these
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remote regions is the first challenge
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currently there are only two
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interconnections connecting north africa
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to europe
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both are located between morocco and
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spain
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two 700 megawatt interconnections one
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completed in 1998 and the second
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completed in 2006
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with a third connection expected to be
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completed sometime before 2030 for a
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total of 2100 megawatts if we wanted to
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transport enough electricity to power
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europe ignoring transport losses and
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storage issues we would need
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592 to 831
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more of these 700 megawatt
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interconnections these aren't just
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simple cables that we lay between
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countries
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they are incredibly complicated and
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expensive pieces of infrastructure the
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third interconnection joining morocco
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and spain's grids is estimated to cost
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150 million dollars an enormous
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investment that will see both countries
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footing half the bill
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592 more of these connections would cost
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at an absolute minimum 8.9 billion
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dollars and that number was found by
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simply multiplying 150 million by 592
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but these connections are the shortest
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route to europe from north africa they
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are going to be the cheapest to build to
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build a truly interconnected grid we are
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going to need even longer
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interconnections connecting tunisia to
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sicily algeria to sardinia and onwards
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to northern italy libya to crete and
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onwards to greece and turkey and to the
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rest of the middle east network all the
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while building enough internal
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interconnections in europe to facilitate
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the passing of the solar paracel
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northwards while wind is traded south
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this plan will take billions to complete
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yet even with these issues european
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leaders have drawn up plans to connect
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north africa and the middle east to
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europe they believe the cost can be
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recovered desertec is or perhaps more
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appropriately was a german-led
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initiative centered around a
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half-trillion dollar investment fund
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that would invest in generation and
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transmission infrastructure across north
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africa and the middle east 55 billion
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was allocated to increasing transmission
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capabilities across the mediterranean
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this investment would go into both high
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voltage alternating current transmission
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over shorter gaps like those from
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morocco to spain and high voltage direct
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current over longer distances
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there is a critical distance where high
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voltage alternating current transmission
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does not make sense
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if we plot transmission losses per
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kilometer for ac and dc transmission it
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would look something like this with dc
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losing less power per kilometer
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however in order to convert our regional
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ac grid power to dc for these long
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distance transmission cables we need
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expensive transformers and converters if
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we instead plot cost versus distance
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counting in this infrastructure it would
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look something like this and we can see
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that the dc and ac lines cross each
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other around the 500 to 800 kilometer
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mark this is the break-even point where
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dc becomes more cost effective
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so lines connecting morocco directly to
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spain which spans only 28 kilometers
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don't make sense for high voltage dc
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while longer lines connecting tunisia to
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italy will likely be high voltage direct
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current lights
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transmission losses for high voltage
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direct current is about three percent
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per 1000 kilometers and germany's
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capital is only 1 800 kilometers from
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tunisia transmitting power with this
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much investment money is perfectly
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feasible the technologies exist
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so let's move into the generation part
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of the desertec plan
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desertec was formulated with
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concentrated solar power in mind which
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works very differently to photovoltaic
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solar panels
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concentrated solar power facilities
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would be spread out along the borders of
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the saharan and arabian deserts
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one such facility already exists in
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morocco and it's the largest
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concentrated solar power plant in the
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world
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it is massive with three separate
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sections nor one two and three each
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using slightly different variations of
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concentrated solar power
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combining to provide
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510 megawatts
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nor 1 and 2 are both trough-based
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systems that use parabolic mirrors with
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the tube located in the mirror's focal
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point the tube contains a synthetic oil
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which collects the heat from the 500 000
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parabolic mirrors spread out over 308
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000 square meters
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this oil becomes extremely hot as high
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as 400 degrees celsius which allows it
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to boil water and heat exchanger to
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drive a steam turbine which provides
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electricity for the grid
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the 400 degree oil is also hot enough to
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melt salt in a molten salt heat storage
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system the molten salt heat storage
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system of nor1 can store enough heat to
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keep the plant operational for three
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hours while nor2 has enough energy for
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seven hours however this salt solidifies
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at 110 degrees and if that happens the
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plant won't work in the morning so nor 1
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and 2 need a fossil fuel burning system
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to keep all the working fluids of the
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system at minimum operating temperatures
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overnight and to keep the oil system
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pumping this fossil fuel burning system
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can also keep the plant operational as a
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reliable baseline energy source
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removing the need for separate natural
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gas peaker plants
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nor3 does not use these parabolic
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mirrors and instead uses a tower system
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it's this striking circular facility to
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the north it looks less like an
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industrial facility and more like a new
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age burning man art installation
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this design allows north 3 to rid itself
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of the oil plumbing and pumps of nor1
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and 2 and instead it uses mirrors
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arranged in concentric circles around a
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central tower the mirrors are then
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controlled to focus light on a single
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point on the tower which directly heats
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the molten salt which is the working
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fluid instead of the oil based system
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the solar concentration here is much
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higher and in turn the temperatures
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attained are much higher with the water
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being heated to 550 degrees
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this allows the tower-based system to
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use more efficient steam turbines and
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using molten salt as the working fluid
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removes the need for an oil to molten
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salt heat exchanger in the heat storage
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system north 3 is the world's only
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operating tower based concentrated solar
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power system with molten salt storage
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after 2019's shutdown of nevada's
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crescent dunes plant the crescent dunes
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plant ceased operation in 2019 after
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only four years of operation nv energy
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broke its purchasing contract with the
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plant after it failed to meet
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performance requirements being marred by
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maintenance issues including an
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eight-month shutdown due to a leak in
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the molten salt tank even when fully
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operational the plant's electricity cost
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135 dollars per megawatt hour while a
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nearby photovoltaic plant was managing
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30 dollars per megawatt hour and here
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lies the crux of the issue concentrated
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solar power costs per megawatt was
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extremely competitive with photovoltaics
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in 2009 but in the last decade
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photovoltaics have become obscenely
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cheap concentrated solar power simply
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cannot compete in a market like this and
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the same can be seen for nor one two and
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three however they are currently being
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measured on a metric called levelized
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cost of electricity which is an average
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of the cost to generate electricity over
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the entire life of the plant
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but this does not factor in the cost of
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storage for photovoltaics which is often
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just an inherent benefit of concentrated
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solar thermal power
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so going forward the industry should be
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using a combined cost of storage and
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cost of electricity metric yet the most
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recent addition to this solar farm is
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nor4 a solar panel farm contributing 73
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megawatts with the rise of cheap solar
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panels desertec contrary to what you
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might expect was doomed for failure
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concentrated solar thermal power by
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nature needs a lot of land
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the plant has a minimum viable operating
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temperature and to achieve that we need
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enough mirrors to reflect that light
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solar panels do not have this problem
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solar panels can be fitted on top of
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homes over car parks or even in farmers
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fields to help shade plants that need
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shade we don't need massive plots of
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land to make them work and because they
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are so cheap it's perfectly feasible to
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build smaller solar farms in germany and
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avoid those transmission losses and not
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incur the massive financial risk of
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investing billions into a country that
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is not your own
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that's particularly important because a
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lot of investors are very hesitant to
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put money into these often volatile
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countries we need to look no further
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than the 2013 attack on a bp natural gas
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plant in algeria to see why this would
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be considered a risky investment in many
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parts of north africa
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it's a vital economic resource for
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algeria yet it sits isolated in the
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midst of a vast desert that's a transit
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route for al qaeda in north africa
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no wonder it was so difficult to defend
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and such a tempting target for the
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militants
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this is all exactly why germany is
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instead investing in its own domestic
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photovoltaic generation and in 2020
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solar power accounted for 10 of
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germany's power generation
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this idea of european countries drawing
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natural resources from africa to benefit
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their own economy has some undeniable
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problematic historic parallels
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any foreign investment like this is
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going to come with some guarantees of
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supply for europe beyond the
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difficulties of organizing cross-border
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cooperation like this
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that's not going to go down well when
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the country hosting these plants needs
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the power for their own grid to power
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their economy or simply stabilize their
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own grid for current needs it becomes
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even more problematic when you consider
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the amount of water these facilities
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need for cooling for the steam turbine
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and to keep the mirrors clean this
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facility in morocco uses 2.5 to 3
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billion liters of water every year
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taking water from a dam 12 kilometers
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away
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morocco is already susceptible to
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droughts so scaling these water demands
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up just to feed europe's power needs
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while taking water away from the farms
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that feed moroccan citizens is even more
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problematic to truly scale this power
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generation some technological
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improvement that reduces the consumption
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of water would be needed or just paired
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the facilities with desalination plants
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and use the extra water if any to
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irrigate local farms to boost local
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economies even more
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for this dream of turning the earth's
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barren deserts into energy generation
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centers to come true it has to be a
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grassroots movement not some new age
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imperialism mega project that comes with
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a whole host of guarantees in exchange
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for the nearly half trillion dollar
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investment
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north africa is one of the hardest hit
[842]
regions in the world by climate change
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with desertification and water scarcity
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becoming a serious issue this plan
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despite its surface level good
[852]
intentions
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sought to exploit these countries that
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have suffered most as a result of
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western industrialization we don't need
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to look for proof that this was their
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intention the moment the technology
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developed to allow european countries to
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provide their renewable power needs
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within their own borders the plan
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disintegrated the plan was never about
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helping african nations
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but the idea isn't dead in the water
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these countries do have the natural
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resources to benefit from solar energy
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morocco is in the best position to lead
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by example its proximity to spain allows
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relatively short interconnections to the
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european grid its government is
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relatively stable compared to its north
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african neighbours with a political
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stability index of minus 0.33
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algeria tunisia libya and egypt are all
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much lower and while morocco has
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abundant solar resources it also
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benefits from consistent desert winds
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along its coast
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morocco has the potential to invest in
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its own energy needs while exporting
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access to europe leading by example
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slowly shifting away from being a net
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energy importer of fossil fuels and
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becoming an energy exporter local
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infrastructure to benefit local people
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first an african nation using its
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resources to benefit itself first and
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foremost the potential for africa's
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solar energy future is undeniable the
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technologies to facilitate cross-border
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energy trading exist
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and investments are happening to
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increase capacity for trade with this
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third interconnector between morocco and
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spain
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funded equally by both sides ensuring a
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level playing field
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figuring out the best practice for
[967]
growing and improving our electric grids
[970]
is incredibly complicated electricity
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grids are effectively the largest
[975]
machines on the planet hundreds of
[977]
generators scattered across countries
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connected together by wires relays and
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switches the task of managing that by
[985]
hand and making sensible decisions for a
[988]
single human is impossible and more and
[991]
more of the grid infrastructure is
[993]
turning towards a smart grid controlled
[995]
by algorithms battery firms employ
[998]
coding and math experts to develop
[1000]
algorithms to allow them to buy and sell
[1003]
the electricity they store to maximize
[1006]
profit and coding jobs like that are
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