Morocco: a desert solar case study

A country which has historically been viewed as pretty resource barren, now trying to harness the potential of the huge amount of sunlight it receives. That country is Morocco, who have a substantial chunk of the Sahara desert within their borders. As it turns out, the road to being a climate leader is not without its challenges. You probably didn't need telling that the Sahara desert gets its fair share of sun. What it might surprise you to know is that if we covered the Sahara in solar panels, we could produce enough electricity to power Europe, 7,000 times over with next to no carbon emissions. Karim Elgendy and Julia Ravey...

Karim - The first issue is the intermittency of solar energy or the fact that electricity is only generated during the day. This requires a significant amount of storage capacity. The cost of the storage or specifically batteries used to be quite high, but it is consistently coming down on a per kilowat hour basis. The other challenge of a technical challenge, and it's a distance between where energy is generated in north Africa and where it is consumed in Europe. And that distance is quite long, which could lead to energy losses in transmission. Dust is also a major issue and high temperatures lead to reduced performance in solar panels, the panels do receive a lot of energy, but high temperatures around them and especially on the surface of the solar panel means that the performances is suboptimal.

Julia - This last factor has led Morocco to invest in solar projects, different from the PV panels that we've been discussing in the show. Another way of generating electricity from the sun is through concentrating the sun's rays into a focal point and using the enormous heat this can generate.

Karim - Concentrated solar power tends to be more expensive than PV, but it's also more economic in terms of energy storage, because batteries were still quite expensive.

Julia - The largest concentrated solar projects in Morocco are Noor I, II and III, Noor I and II are trough based systems with 500,000 parabolic mirrors arranged in rows at angles. So they will direct sunlight towards a tube. In these tubes is a synthetic oil, which is heated up to 400 degrees. This is then used to boil water in a heat exchanger to drive a steam turbine, which produces the electricity. One drawback of the project is when the sun stops shining the plant does have to use fossil fuels to keep that oil hot enough, not to freeze overnight.

Karim - It provides enough storage hours for the energy generated during the day to be used later in the evening, and as close to 24 hours of generation as possible

Julia - Instead of parabolic mirrors in rows Noor III, a system where thousands of flat mirrors are placed in concentric circles around the central 250 meter tall tower, which directly heats molten salt. This acts as the working fluid instead of the oil in Noor I and II. It's seriously, visually impressive. It looks a bit like a space shuttle ready for launch surrounded by rows and rows of shining sheets of glass. For this reason, it has become the poster boy for Morocco's quest to become a big player in clean energy.

Karim - Particularly clean water, fresh water is required in the case of concentrating solar power, and because these mirrors need to be incredibly clean in order to reflect all of the direct radiation that hits it, remember CSB works differently and it only works with direct radiation, not the ambient light in the skies. The water footprint that is required by this is certainly a problem in a country such as Morocco, where water is becoming increasingly scarce. And also the desalination environmental footprint becomes an inhibitor and an additional cost on such projects. So there's a certain balance to be made here between the water footprint, which has in some cases, an energy and a carbon footprint, and the benefits to be made out of renewable energy.

Julia - Another problem comes with trying to transport all that clean energy from Morocco to Europe.

Karim- Morocco exports excessive electricity to Europe via cables, which go through Spain, but there are new plans by a UK company called Xlinks to export electricity directly from Morocco to the UK, to Devon directly via sea cables. The project's quite unique, actually it aims to develop more than 10 GWh of new solar and wind farms, on an area that is the size of a city as big as Edinburgh to use 20 Gigot hours of battery storage in order to condense these 10 GW into 3.6 GW of constant power. So basically using batteries to deal with intermittency as the cost of batteries has come down. This is now viable to do without government subsidies. The transmission losses will also be minimized by using direct current rather than alternative current in the section between Morocco and the UK. According to the proponents of the project, it could provide 8% of the UK energy needs, electricity needs rather, that suggests that batteries have now come down in cost enough to make up for the intermittency issues and to provide constant power that can be used for base loads. It's competing with fossil fuels and also competing with nuclear.

Julia - These amazing feats of engineering are a marvel to even think about, but Karim has doubts as to whether Morocco alone holds the key to getting us out of the world's current energy predicament.

Karim - Morocco does have very ambitious plans to increase its renewable energy capacity so that they represent 52%, more than half of its total electricity generation capacity by the end of this decade, so 2030. It is about 10 GW of renewable energy capacity by 2030. So 10 GW, remember that is quite a small amount of electricity generation that is required for Morocco, because Morocco's energy needs are quite limited. Compare that to 580 GWh, which is what Europe and the UK need currently. This is the amount of electricity that is sourced from non-renewable sources. So yes, 10 GW would be nice. Yes, that would help, but it will certainly not fix Europe's problems.