Battery storage allows the sun to shine in the day and at night

Abu Dhabi’s new giant solar and battery combination will provide electricity around the clock

The Dhafra solar power plant near Abu Dhabi. Solar photovoltaic power in the Middle East has achieved very low costs. Bloomberg

Critics of renewable energy love to point out that the “wind doesn’t always blow and the sun doesn’t always shine”.

After decades of research by scientists confirming this observation, Abu Dhabi has the solution. Its giant solar and battery combination will provide electricity day and night, summer and winter.

The project was announced at Abu Dhabi Sustainability Week last week, by Dr Sultan Al Jaber, the UAE’s Minister of Industry and Advanced Technology. Located at Al Azeezah south of Abu Dhabi city, Masdar and Emirates Water and Electricity Company will together develop the project, costing $6 billion. It combines 5.2 gigawatts of solar power with 19 gigawatt-hours of battery storage. It should be able to output a steady 1 gigawatt, which it could keep up for 19 hours in conditions of zero Sun.

Solar photovoltaic power in the Middle East has achieved startlingly low costs. Ewec’s Al Dhafra project was awarded in April 2020 at 4.97 fils (1.35 US cents) per kilowatt-hour, at the time the lowest in the world. This was the cheapest electricity generation from any source globally. In contrast, the US’s target was to reach 3 US cents per kilowatt-hour by 2030.

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But even in the sunny Gulf, solar power achieves a capacity factor of only about 20-25 per cent – that is, the ratio of a plant’s average output over a year to its stated maximum. Generation is zero at night, lower in the shorter days and in winter, falls when ambient temperatures are high, and is reduced at times by clouds, haze, dust and sandstorms.

A back-of-the-envelope calculation suggests that the system at Al Azeezah could deliver reliable baseload power at about 6 US cents per kilowatt-hour over a 20-year operating life. That is already cheaper than nuclear power, another large-scale, low-carbon option for baseload. And costs will fall further as solar, and in particular batteries, enjoy further declines in purchase prices.

It is also cheaper than conventional generation with natural gas, except in areas with very low gas prices. And the long-term use of natural gas is not possible within the UAE’s net-zero carbon target, unless teamed with carbon capture and storage, which would raise its cost.

The solar-plus-storage combo compares favourably with the 7.3 cents per kilowatt-hour that the Dubai Electricity and Water Authority (Dewa) achieved for its concentrating solar plant in 2017. That plant uses molten salts to store heat so it can also provide night-time electricity, for up to 15 hours.

Solar with storage in the Gulf has the advantage of matching well to demand patterns. Air-conditioning accounts for up to 70 per cent of the UAE’s electricity use during summer. With enough storage to get through the night, solar can cover much of national demand. This is in contrast to other heavy users of solar power in northern Europe, such as the Netherlands and Germany, where peak electricity demand for heating comes during the short daylight hours of winter.

Another option for long-term energy storage is pumped hydropower, where water is sent to a higher reservoir behind a dam when electricity is in surplus, then allowed to flow to lower levels through a turbine at times of deficit.

Dewa’s pumped hydroelectric centre at Hatta, with 250 megawatts of capacity and six hours of storage, is expected to be completed by the end of the first half of this year.

At its recent energy summit, Ras Al Khaimah also revealed plans for a massive, 5 gigawatt pumped hydroelectric plant with up to 12 hours of storage in its mountains.

Finally, other renewable options such as wind, geothermal and waste combustion generate independently of solar output and complement it.

While lithium-ion batteries are the most familiar today, they may not be the main long-term option. Other chemistries, such as sodium-ion, and different concepts entirely, such as flow batteries using metal salts, may eventually have advantages of lower cost, safety, large scale or avoidance of scarce materials.

All these methods have their place. Batteries and other energy storage options do not just hold electricity for future use. They have other functions such as stabilising the grid in case of surges of demand or the sudden power cut of a generating unit and keeping the frequency of its alternating current within standard levels to avoid damaging equipment or causing blackouts. Batteries close to consumers help ease the burden on power lines at times of high demand. These different storage and grid technologies contribute in various ways to stable, reliable electricity.

Achieving reliable, low-cost and continuous electricity from solar plus battery storage has three important implications.

First, as President Sheikh Mohamed said, it is “a significant step on the UAE’s journey towards net zero”.

Second, it will help to power new businesses in the UAE. These could include large industrial users, such as aluminium smelting. Some of these already buy certified low-carbon nuclear and solar electricity from Ewec and Dewa. It can expand to cover data centres, an exploding sector for both investment and electricity use, as artificial intelligence booms.

Third, it will mean the end of oil burning in the power sector in the Middle East, and the steady reduction in gas. The UAE’s gas consumption for power has already dropped significantly, mostly because of the start-up of the Barakah nuclear plant, and improved efficiency.

Saudi Arabia plans to phase out oil in favour of a mix of renewables and gas. Oman, Jordan, Egypt and Morocco are among other regional countries forging ahead with solar and wind power. Those suffering electricity crises, such as Lebanon, Yemen, Syria, Iran, Iraq and Libya can tap into solar. The gas saved from power generation can be used in industries such as petrochemicals, or converted to clean products such as “blue” hydrogen and ammonia.

This advance is crucial for the future demand for gas, the supply and cost of low-carbon electricity, and the region’s industrial competitiveness. Other sunny regions with abundant land can benefit similarly.

In the Gulf, the sun will shine even at night.

Robin M. Mills is chief executive of Qamar Energy, and author of The Myth of the Oil Crisis