Renewable Energy Island – Part 2

In the last part, we explained the fundamental question of energy supply on islands. In this part, we will go into more detail on how to provide a secure and ecological power supply on islands: With a Virtual Power Plant, many small generating units can be aggregated to form a secure and efficient island power supply, thus reducing the amount of fossil fuels used. 
 

Self-sufficient island power grids with a large share of renewable energies usually consist of many small-scale, individual units that either consume electricity, produce electricity or store electricity. These units are networked via mobile data connections with a central control station that monitors and controls all events in its area of operation. Together they form a so-called Virtual Power Plant (VPP). The power production of such a Virtual Power Plant can be controlled similar to the power production of any regular large-scale power plant.

In recent years, Virtual Power Plants have shown that they can provide a reliable power supply and that an aggregated system comprised of power producers, consumers and storage facilities is economically sound. Already today, Virtual Power Plants demonstrate that they are an integral asset of a modern power grid. Operations in various national grids prove their usefulness, although at the moment VPPs are only one market player among others. 

On islands, though, VPPs would probably be responsible for the entire power supply, including the control of the island power grid. This brings additional benefits such as the forecasting and coordination of decentralized power generators, consumers and storage in real time, the provision of reserve power within seconds, the highly flexible ability to react to weather influences, and much more. This may come in cheaper than installing a centralized infrastructure, but it will definitively be greener and because of the decentralized network topology also safer.

In order to make the island’s power grid efficient and secure, the consumer side needs to be integrated into the Virtual Power Plant of the island. Large electricity consumers such as hotels or businesses play a decisive role, as their consumption processes are an indicator for the needed flexibility in order to maintain a stable grid. In case of potential power shortages, intelligent load management protects the island’s power grid by automatically aligning the electricity production and consumption processes. 

For the compensation of voltage peaks and drops, inert power consumption processes are helpful assets of a virtual power plant: Refrigerating machines as well as air conditioning systems are able to briefly throttle or ramp up their compressors by means that do not have a direct effect on their primary objective. This turns ice storage tanks into cold power batteries, for example. Furthermore, processes such as vehicle loading stations, port facilities, pumping stations and other machinery whose maximum consumption can be shifted or throttled over time can be utilized in a similar fashion. 

With the help of smart meters,even small electricity consumers such as households and small businesses can provide flexibility to the power grid.