Instead of commonly seen black PV panels, Noor uses concentrated solar power. A field of 2 million giant mirrors reflects the sun’s rays onto a central receiver that sits at the top of a 247-meter (810-foot) tower. The concentrated sunlight melts molten salt to 600 degrees Celsius (1,112 degrees Fahrenheit). That makes steam, which spins turbines, generating electricity even hours after sunset.
Morocco’s massive Noor concentrated solar power project is one of the region’s largest renewable energy installations Image: Xinhua/SEPCO
Moroccans spend around $110 (€94) of their $550 average monthly income on electricity. This is in a hot and dry country, where residents rely on air conditioning or a fan to stay cool. It’s regularly over 40 degrees Celsius in Ouarzazate during the summer, and the number of hot days and nights has roughly doubled in the region since the 1970s.
As the Noor solar complex took shape in 2016, it carried the hope of a rapid energy transition Image: FADEL SENNA
This expense is partly down to the fact that Morocco does not produce any fossil fuels domestically, and imports about 90% of its coal, oil and gas, Fakir explained. Energy market and price fluctuations mean fossil fuel imports consume a major portion of the national budget, making the switch away from planet-heating coal, oil and gas increasingly urgent.
Just a few miles southwest of the Noor/ Ouarzazate solar power station sits the city of Ouarzazate.
Ouarzazate is a city and capital of Ouarzazate Province in the region of Drâa-Tafilalet, south-central Morocco.
Ouarzazate is a primary tourist destination in Morocco during the holidays, as well as a starting point for excursions into and across the Draa Valley and the desert.
Ouarzazate was home to a thriving Jewish community. In 1954, about 170 Jews lived in the Mellah. The “Old Synagogue”, a synagogue said to be nearly 300 years old, is located in Ouarzazate.
Film is a major industry in Ouarazazate and constitute a major part of its economy. Its success is due to the presence of desert landscapes and historical architecture, the availability of trained technicians, low productions costs, and Morocco’s streamlined process for obtaining film permits.
Interestingly, Ouarazazate lies north of Austin, with a latitude that places it between Austin and Waco. It’s about as toasty-warm as Austin, but much drier.
Morocco
Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to the east; the Spanish exclaves of Ceuta, Melilla and Peñón de Vélez de la Gomera along the north […] It has a population of approximately 37 million. Its capital is Rabat, while its largest city is Casablanca.
The region constituting Morocco has been inhabited since the Paleolithic era, more than 300,000 years ago.[…] Morocco is regarded as one of the world’s oldest continuously existing states.
Morocco was the only North African nation to escape Ottoman dominion.
Morocco’s local name stems from the Arabic al-Maghrib (المغرب, transl. the land of the sunset; the west), with the Kingdom’s official Arabic name being al-Mamlakah al-Maghribīyah (المملكة المغربية; transl. the kingdom of sunset; the western kingdom) and official Berber name Tageldit n Lmeɣrib (ⵜⴰⴳⵍⴷⵉⵜ ⵏ ⵍⵎⵖⵔⵉⴱ).
The area of present-day Morocco has been inhabited since at least Paleolithic times, beginning sometime between 190,000 and 90,000 BC. A recent publication has suggested that there is evidence for even earlier human habitation of the area: Homo sapiens fossils that had been discovered in the late 2000s near the Atlantic coast in Jebel Irhoud were recently dated to roughly 315,000 years ago. Hominin fossils from Thomas Quarry I in Casablanca, published in 2026, push evidence of hominin presence in the region back to approximately 773,000 years ago, near the root of the Homo sapiens lineage. During the Upper Paleolithic, the Maghreb was more fertile than it is today, resembling a savanna, in contrast to its modern arid landscape.
Salt is melted in the Morrocan concentrated solar power (CSP). The salt of choice for these CSPs is specially formulated mixture of sodium nitrate and potassium nitrate. Those salts can be heated to well over 500°C, store enormous amounts of thermal energy, and then release that heat hours later to make steam and generate electricity even after the Sun has gone down.
What is Salt?
Salt is a crystalline compound made from positively and negatively charged ions held together by electrical attraction.
Examples include:
Sodium chloride (NaCl – table salt)
Potassium chloride (KCl)
Calcium carbonate (limestone)
Magnesium sulfate (Epsom salt)
Copper sulfate (bright blue crystals)
Sodium bicarbonate (baking soda, technically also a salt)
As Elder G so poetically states:
So when you sprinkle salt on your dinner, you’re holding:
atoms forged in exploding stars,
assembled into crystals on Earth,
harvested from oceans or ancient seas,
and adding flavor to your mashed potatoes.
How Much Salt We Talkin’?
Elder G to the rescue:
The answer is delightfully staggering.
The entire Noor Ouarzazate complex is estimated to contain between 84,000 and 140,000 metric tons of molten salt, depending on the exact mix of operating units and storage inventories. The environmental planning documents for the project cite that range for the complete complex.
To put that in perspective:
84,000 metric tons = about 185 million pounds
140,000 metric tons = about 309 million pounds
What kind of salt?
It isn’t table salt (sodium chloride). The storage medium is typically:
60% sodium nitrate (NaNO₃)
40% potassium nitrate (KNO₃)
This mixture has several advantages:
melts at a relatively low temperature (around 220°C),
remains stable at temperatures approaching 565°C,
stores enormous amounts of heat,
is comparatively inexpensive,
and can be pumped like a thick liquid when hot. (Scribd)
A railroad hopper car typically carries around 100 tons of material. So:
84,000 tons would fill roughly 840 railcars.
140,000 tons would fill about 1,400 railcars.
Imagine a freight train 15 to 20 miles long, carrying nothing but solar-storage salt.
So What Happens when the Salt Freezes?
It’s bad. Way bad. Don’t let it happen. Keep it hot – always.
Again, Elder G:
Here’s the surprisingly dramatic truth: they never let it cool down to a solid state in the first place.
If the salt were allowed to cool and freeze inside the pipes or heat exchangers, it would harden into massive, rock-solid blocks. Solid salt expands as it melts again, which can burst pipes, ruin pumps, and completely paralyze a plant.
Because of this, the primary rule of operating a molten salt facility is never let the salt freeze.
How They Keep the Salt Liquid for Decades
Instead of pulverizing or breaking up solid salt, engineers design the system to keep it flowing like water 24/7 for the plant’s 25 to 30-year operational life:
The “Cold” Tank Isn’t Cold: Even after the salt gives off its heat to turn water into steam, it only drops to about 260°C to 290°C (500°F–550°F). The standard “Solar Salt” mixture (60% sodium nitrate, 40% potassium nitrate) melts at roughly 220°C (428°F), so even the “cold” side stays well above its freezing point.
Electric Heat Tracing: Every single pipe, valve, and vessel holding salt is wrapped in electric heat tracing cables and thick insulation. If the sun is blocked for days or the plant is shut down for maintenance, electric heaters kick in automatically to keep the plumbing warm.
Eutectic Salt Blends: Engineers mix specific proportions of salts (and sometimes add calcium nitrate) to create a eutectic mixture. This chemical blend lowers the overall melting point significantly compared to pure individual salts, widening the safety margin against freezing.
Self-Draining Pipes: If a section of the field needs to go offline, the system is designed with steep gradients so gravity drains the liquid salt back into the insulated main storage tanks before it has a chance to cool.
What happens if it does freeze?
It has happened in rare, catastrophic plant failures (like prolonged power blackouts during maintenance). Unfreezing a block of salt inside an industrial heat exchanger requires months of painstaking external heating with specialized electric blankets or gas torches.
And I’m guessing when this happens someone needs to update their resume.
