Morocco Expands Seawater Desalination Plants, Moving to Renewable-Energy Operation

Explanation

Morocco, in North Africa, is advancing plans to expand its seawater desalination plants and run them on renewable energy. The country suffers from chronic drought, making the securing of water for agriculture and drinking a national challenge.

The mainstream method of seawater desalination is 'reverse osmosis (RO).' Normally, when water of low concentration and water of high concentration are separated by a semi-permeable membrane, water moves from the low-concentration side to the high-concentration side (osmosis). In reverse osmosis, pressure exceeding the osmotic pressure is applied to the seawater side, pushing only water molecules through to the other side of the membrane to extract fresh water. The need for large amounts of electricity to generate this pressure is desalination's biggest weakness—running it on fossil fuels drives up both cost and CO2 emissions. Blessed with abundant sunshine, Morocco has therefore moved to power desalination with a combination of solar and wind energy.

Morocco is already known as a renewable energy leader, having built the Noor concentrated solar power plant, one of the largest of its kind in the world. The country's strategy, combining conditions of water scarcity with abundant renewable energy resources, is being closely watched worldwide as a model case for water resource issues in the age of climate change.