Managing 9+ GW in 14 countries to keep the lights on in an intermittent world

While the world struggles to adjust to climate change and an increase in extreme natural events, and as we respond by replacing fossil power with renewables, global energy grids face growing stresses and potential outages.

 

Historical solutions to these stresses revolved around expensive infrastructure upgrades, including centralized standby power stations (or "peaker plants") to boost energy supply. In today’s increasingly digitized, decentralized and decarbonized context, the focus has shifted to reducing demand on a large scale through Virtual Power Plants during such events. This emerging discipline is known as Demand Response (DR) .

 

Demand Response is defined by the International Energy Agency¹ as “balancing the demand on power grids by encouraging customers to shift electricity demand to times when electricity is more plentiful or other demand is lower.”

With Taiwan aiming for net-zero emissions by 2050, DR plays a critical role in integrating renewables while maintaining grid reliability.  Taiwan Power Company’s (Taipower’s)   Energy Trading Platform currently has several DR programs, including Spinning Reserve, Supplemental Reserve and Regulation Reserve, which allow businesses to receive compensation for participating in grid stabilization efforts.

The NOC is the heart of a Virtual Power Plant (VPP), making sure all aggregated demand response assets are functioning optimally. A good day at the NOC is when the public has no reason to know that it even exists. On an average day, however, the NOC ensures that electricity systems continue to function as normal when more routine, but increasingly frequent, events occur. These include: power station repairs; interconnector outages; a mismatch between generation forecasts and demand.

 

Enel X’s Global NOC is based in Dublin, Ireland, chosen for its intermediate timezone, cultural diversity, strong IT heritage, and increasingly virtual skills base. Enel X also operates a local NOC in Taiwan to support local customers.

 

While there is room for engineers in the NOC, its modern skill-set reflects the full breadth of today’s digitalization, decentralization and decarbonization agenda. Enel X’s Global NOC in Dublin is led by former airline operations controller, and includes recruits from finance, trading, IT, security, customer care and retail backgrounds. Given its truly global nature the NOC also hosts a wide range of nationalities and languages – such as Mandarin, Polish, Italian, and Portuguese.

 

At 9GW, Enel X operates the world’s largest commercial & industrial (C&I) VPP, streaming live data for over 15,000 sites across 14 countries and dispatching the required energy reduction or generation responses in real time. VPPs have become an integral part of global power systems in how they support multiple national grids, promote global inter-operability, enhance energy security and help advance the uptake of renewable energy.

 

An extreme example of  dispatch events is the series of devasting earthquakes and aftershocks in Taiwan during April 2024.

 

On 3rd April, when Taiwan was struck by its strongest earthquake in 25 years, Taipower issued a dispatch notice at 4:30pm, calling for reserve power to help stabilize the grid. Enel X’s NOC immediately mobilized and aggregated the energy load of over 50 C&I scale users, providing nearly 30 megawatts (MW) of DR (approximately equivalent to the installed capacity of the Liwu Hydropower Plant³  in eastern Taiwan, and similar to the energy demand of a large factory.). Companies from sectors including textiles, chemical processing, hospitals, metal processing, food, agriculture and hotels activated their flexible energy resources to help maintain grid frequency and stability over two hours.

 

Throughout this challenging period, Enel X’s network operations team responded in real-time to stabilize the grid, both by reducing electricity consumption from non-critical devices and by shifting energy use from the grid. On April 15, 12 days after the initial earthquake, a generator trip caused another low frequency event. This time, the NOC dispatched nearly 1,000 battery swapping stations, through its partner Gogoro, responding within five seconds to reduce energy consumption by 11MW for 30 minutes.

 

This is primary an example of how the energy transition is creating new infrastructure and opportunities that can be used to support the wider community in ways for which they were not originally designed. 

Anticipating the need for extra energy reserves ahead of the summer period, the Australian Energy Market Operator (AEMO) procured additional reserve capacity. This included Enel X’s DR customers, who curtailed their energy usage on 14 occasions to release pressure on the grid throughout the challenging summer conditions.

 

United States:

The United States’ diverse geography exposes it to extreme weather at both ends of the temperature spectrum, triggering grid dispatch events by both heat and cold. During California's 2022 heatwave (with temperatures reaching 43°C), electricity demand surged to a record 52GW, mainly from increased air conditioning usage, prompting CAISO to activate DR providers like Enel X for over 63 hours during a 4-day period.

 

That same year, Winter Storm Elliott brought record cold temperatures (-31°C in Denver) across a huge part of the United States, causing heating demand spikes while simultaneously freezing natural gas infrastructure. Millions of households across the country lost power at some point during the storm. Again, participating Enel (Enel X’s parent company) DR customers made a significant contribution to helping the system regain stability, with grid operators dispatching 4,108 MW of Enel’s portfolio across 5,000 registrations in north eastern USA over 2 days.

With the growing share of renewable energy and increasing grid volatility, DR is critical to ensuring reliable and secure energy in Taiwan. For VPP participants, DR participation provides multiple benefits:

 

• Advance notice of power outages – allowing companies to schedule their operations around any potential disruption and to protect their facilities from possible damage;
• Decarbonising energy supply – helping grids balance demand with more variable renewables supply, particularly by maintaining a constant frequency (typically 60 hertz in Taiwan);
• Avoiding the need to build or operate fossil-fuelled power stations – Enel X’s 9GW VPP is a clean, instantly-deployable and cost-effective equivalent to the effect of bringing online 10 of Taiwan’s Linkou Coal plants (e.g. Linkou#1, 800MW).
• Contributing to the Energy Saving Obligation – the actual loads reduced when responding to a demand response event are recognized as energy-saving performances, helping major energy users to fulfill the increased obligation.
• A new and predictable revenue stream – DR programs pay companies that can be flexible with their energy use and production. Many demand response participants reinvest the revenue earned into sustainability projects.

 

^{1. International Energy Agency, “Demand Response,” IEA, accessed April 18, 2025.}

^{2. As of October 2024}

^{3. Taiwan Power Company’s unit power generation volume, Taiwan Power Company.}