BALANCING AN INCREASINGLY FLUCTUATING GRID WITH ENERGY STORAGE

Inherently, one of the key issues in modern grid network operation is managing the imbalance between the amount of energy generated and the load, particularly during times of peak demand. With the increase in weather-dependent renewable production, more diverse and frequent grid frequency fluctuations are becoming a more acute problem. What can utilities do to minimise the impact of these fluctuations on secure, safe and reliable supply while contending with an aged grid infrastructure?

Here, Alexandra Goodson, Product Marketing Manager for Energy Storage Solutions at ABB, explains how energy storage offers one of the easiest and quickest ways to address the variable gap between demand and supply for grid operators.

The recent geopolitical climate was quick to expose vulnerabilities within Europe’s electrical system, one of the world’s largest interconnected grids, and shine a new light on the issue of energy security.

In response, the European energy transition has become no longer just a sustainable matter, but an economical and operationally critical one.

This is evident as countries around Europe continue to rapidly accelerate projects that were already underway to meet net-zero emissions targets.

In a seismic shift in the energy landscape, EU solar power doubled in 2022.1 At the same time, the EU’s natural gas demand fell by 13% in 2022, its steepest drop in history and the equivalent of the same amount needed to supply over 40 million homes.2

But while this accelerated inevitable shift has helped Europe avoid predicted blackouts and build resilience, it continues to put its electricity network under its greatest strain yet.

Maintaining the equilibrium point

The equilibrium point for the European grid network is at a frequency of 50 Hertz. To guarantee a reliable and secure electricity supply, the consumption of electrical energy must be equal to the production at any time.

If there is too much electricity and low demand, the electrical frequency increases which, by design, can cause power plants to disconnect from the grid after a period of time.

In the case of high demand and low electricity availability, the frequency drops. In the worst case, this change in transmission flows could result in a power outage.

The inherent variability of wind and solar, coupled with potential imbalances in supply and demand, make maintaining a steady frequency on the existing grid problematic.

Put simply, because solar and wind power can only be generated when the sun is shining or the wind is blowing, they cannot provide the consistent, base load generation required by an aged grid system founded on the assumption of steady, reliable supply.

Add to the mix, a changing grid profile led by evolving electricity needs and rapid electrification driven by electric mobility, data centres, and emerging industries, proves the case that Europe needs new solutions to maintain its complex grid – and fast.

Battery energy storage

One answer can be found in the adoption of Battery Energy Storage Systems (BESS). Although not new, utility-scale energy storage systems are quickly coming coming to the fore as a way for grid operators to smooth the 24-hour load cycle.

The BESS can be charged with excess solar or offshore wind while discharging when dispatched by grid operators to support low frequency events.

The flexibility of a BESS encourages the increase in renewable generation while providing a dispatchable mechanism for grid operators to balance the energy supply and demand. In addition to supporting frequency variability, BESS can provide bulk shifting of energy which can reduce peak demand on the grid.

When partnered with an energy management system (EMS), monitoring and diagnostics, the BESS allows operators to optimise power production by leveraging peak shaving, load-lifting, and maximising self-consumption.

The flexibility this brings is vital to enable the most efficient use of the existing infrastructure and –importantly in Europe - boost the capacity needs of interconnections. But there’s more.

Smart gets smarter

The integration of Artificial Intelligence (AI) takes BESS to a new level of smart operation.

As many grid operators will know, energy storage operations can be complex. They typically involve constant monitoring of everything, from the BESS status, solar and wind outputs to weather conditions and seasonality. Add to that the need to make decisions about when to charge and discharge the BESS in real-time, and the result can be challenging for human operators. By introducing state-of-the-art AI, it is now possible to achieve all of this in real-time, around-the-clock, for a much more effective and efficient energy storage operation.

This unique innovation takes a fourpronged approach: data acquisition, prediction, simulation, and optimization. Using advanced machine learning, the system can constantly handle, analyze, and exploit data. This data insight is partnered with wider weather, seasonality, and market intelligence to forecast future supply and demand expectations. As a final step, a simulation quantifies how closely the predictions resemble the real physical measures to provide further validation.

The result is a radical new potential for energy and asset optimization. Through predictive analytics, it will allow operators to save and distribute renewable generation more effectively and better prepare for upcoming demand. It can also ensure ‘business as usual’ in the ability to identify and address issues before they escalate and anticipate similar failures or performance constraints for optimum performance at all times.

As the energy crisis continues to push the EU to rethink its approach to energy and interdependency, there’s no doubt that the renewables transition will continue in high gear and, in turn, bring new complexities to grid stability.

By harnessing BESS innovation operators can address these challenges more effectively, build better resilience and help to ensure Europe’s energy transition emerges from the energy crisis even stronger.

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