Enerweb, Microsoft power Eskom's 800MW Virtual Power Station to help meet winter electricity demand

Arguably South Africa's smallest and cleanest burning power station, Enerweb's Microsoft-powered Virtual Power Station (VPS) is ready to deliver during the coming winter.

Enerweb developed and implemented the VPS for Eskom in 2007. Eskom uses the VPS as a means to schedule all its controllable demand side resources and view available customer 'NegaWatts'.

“This NegaWatt generation capacity reduces Eskom's reliance on meeting reserve margin needs with costly gas turbine generation plants, and avoids load shedding. A total of 854MW of customer load is certified and available for dispatching through Eskom's National Control,” says Rob Surtees, Managing Director of Enerweb.

From an operational point of view, the VPS is indistinguishable from physical power stations. When additional load is needed because of an unexpected shortage or an expected peak, the SO can dispatch the VPS as it would an emergency or supplemental generator.

The VPS is an enterprise-grade system built using Microsoft development products, and is consistent with Eskom's standardisation on Microsoft technologies.

As a Microsoft Software Development Partner, Enerweb utilised Visual Studio 2010 and Team Foundation Server 2010 to ensure development methodologies. The system runs on the .Net Framework, hosted on the latest Microsoft Server 2008 platforms to provide the highest levels of uptime. It uses Microsoft's Lync 2010 Communications Server to automate its interactive phone dispatch system.

The operations tools have rich interactive interfaces that target both desktops and Windows phone operating systems via Microsoft's Silverlight/XAML technologies, giving operators the ability to run operations using their mobile devices, eg smartphones. This also allows the system to be geared for future Windows 8 Metro-style apps.

Apart from being the cleanest energy source available to the SO, the VPS can be deployed faster than any physical energy source of similar capacity, and can quickly modify its capacity and energy delivery curves.

The effects of supply from the VPS are distributed, thereby reducing network constraints.

There has been much focus in recent years on the 'smart grid', which achieves distributed control through a network of automated, real-time load monitors and switches, eg smart meters, which automatically limit load under certain network conditions. The VPS would in time interface with these systems, thereby adding to the MW available for dispatch.

Electricity grid management in general is moving from a traditional load-following approach towards load-shaping strategies in which demand side resources are managed to meet the available generation and the grid's power delivery capabilities at any given time. With the integration of more renewable and variable generation technologies onto the network, this flexibility becomes critical.

Substantial growth in the number of MW under VPS control is anticipated over the next few years, with the full potential of the VPS and DR in general still to be realised. The VPS will play a key role in South Africa's smart grid architecture of the future, enabling Eskom to optimise usage of its electrical network in an environmentally beneficial manner.