Abu Dhabi Water & Electricity Authority (Adwea) has become the first utility in the Middle East to draw up a strategic masterplan for large-scale energy storage. This has paved the way for a multibillion-dollar project that would reduce the need for additional power generation and ease the integration of the renewable sources of energy and nuclear power into the grid.

The masterplan calls for the roll out of storage capacity at all of the emirate’s 11kV substations, which could lead to a combined capacity of around 1350MW.

Adwea has already installed energy storage capacity at two of its 11kV substations, with batteries being able to store about 20MW. The body is currently evaluating the findings.

“As we understand it, there’s a strategic interest from Abu Dhabi to invest in the wider area of the emirate,” says Claus Rubenius, chairman of UAE-headquartered cleantech company Rubenius, which supplied the storage technology for the pilot projects.

There is some uncertainty over the scope of the plan, as it was devised last year, and Adwea is now under new management.

The financial outlay for the conversion of the substations has also not been established, but is expected to cost billions of dollars. “Because of the economics of scale, it is a difficult question to answer, but it will be anything between $5bn-$10bn,” according to Rubenius.

The rollout across Abu Dhabi could be slowed by the limited availability of the batteries providing storage capacity, says the chairman. Should the supply be resolved, the rollout will be completed within a decade.

“I would say if there was sufficient capacity all substations will have this technology in five to 10 years,” says Rubenius.

By adding storage to the grid, Adwea reduces the demands placed on power generation during the peak load, the daily period during the summer months when consumption is highest. While storage is an expensive option compared with adding additional power generation, those costs are offset by the grid expansion that the utility can forgo by not building new power plants, says Rubenius.

Storing electricity also improves the operability of the grid, an advantage when renewable energy and nuclear power comes online. Renewable energy, such as solar power, is an intermittent source, making it difficult for grid operators to create a stable supply of energy. Similarly, nuclear power runs on a steady output, so that energy would be wasted if it cannot be stored.

Abu Dhabi has set itself the target of sourcing seven per cent of its energy from renewables by 2020. The 100MW Shams concentrated solar power (CSP) plant will come online in 2012, while government-owned cleantech company Masdar is exploring a range of green energy options. The first of four nuclear reactors will come online in 2017.