French energy supplier EDF is building a hybrid microgrid in Singapore, as part of an ambitious project aimed at shifting communities across south-east Asia away from diesel electricity generation.

 

The microgrid is expected to become operational in October this year and will potentially include energy storage systems based on zinc air battery technology and as well as second life electric vehicle (EV) batteries.

EDF is a partner in the Renewable Energy Integration Demonstrator – Singapore (REIDS). Since the initiative was launched in the second half of 2016, three hybrid microgrids have been built and are operational. The plan is to implement up to eight in total, with development occuring into the early 2020s.

Semakau Island, 8km from Singapore, is hosting all of the microgrids, which will collectively produce aggregated power in the megawatt range when all are built.

REIDS, led by Nanyang Technological University (NTU), is the first multi-microgrid demonstration site in the Asia-Pacific and will integrate various generation technologies, including solar PV, wind turbines and diesel generators. Energy storage systems, spanning lithium ion batteries, flow batteries, supercapacitors, as well as waste-to-energy, tidal and power-to-gas technologies will also be used across the different microgrids, which will have different loads.

A unique aspect of the initiative is designing, developing, integrating and managing each microgrid to work on its own but also function as a larger interoperable resource. Up to three low voltage clusters, for demonstrating interoperability, will be deployed.

 

The aim of the REIDS initiative is to build several microgrids and link these up to pool and optimise distributed generation from various resources (Image courtesy of REIDS)

Pooling distributed energy resources

The project is designed to be representative of small islands, isolated villages and emergency power supplies. This could allow for a demonstration of how a group of neighbouring islands, for example, could pool their spare energy capacity and optimise use renewable energy generation from various distributed resources.

REIDS is supported by Singapore Economic Development Board (EDB) and the National Environment Agency (NEA).

NTU is working with a consortium of multinational and regional businesses and industrial players. In addition to EDF, they include Engie, Schneider Electric, General Electric (GE), Vestas, Trina Solar and Adaro Power, as well as Meralco and Bawah.

Experience gained so far from developing and implementing the three operational microgrids, which includes civil works, such as land reclamation and preparation of greenfield sites, has led to activity to promote REIDS as a one-stop-shop.

For the technology providers involved, this approach could accelerate the adoption of their technology. Potential investors or developers, for instance, will see how everything works within a live microgrid system.

 

Visits

Already representatives from governments in south-east Asia have visited the REIDS initiative, including an official from the Department of Energy in the Philippines.

The initiative could help government agencies in the region, and other global islands, in terms of formulating tenders for developing similar microgrids. The tropics can provide challenging environmental conditions, such as high temperatures and high levels of humidity, so the project will yield valuable data on how the various assets perform in these conditions.

From building the microgrids from scratch, the REIDS initiative is working to standardise their development and roll-out, producing guidelines across all aspects from civil works to project development and commissioning, which can help to de-risk future development of such projects.

 

First microgrid

The first of the microgrids went live in 2017 and is operated by French energy company Engie. It includes solar PV arrays, a wind turbine, a battery storage plant and a hydrogen system that produces green hydrogen from surplus renewables generation, which is stored in gas form. The hydrogen is converted into electricity and can also be used to provide ‘fuel’ for hydrogen powered electric vehicles.

As part of the this microgrid, Schneider Electric has provided an energy storage system with grid forming inverters to enable up to 100% of renewable energy penetration.

Engie and Schneider Electric have also developed two software control systems for the microgrid. One is a power management system (PMS) that ensures the system’s stability in the short term, by balancing production, storage and consumption, enabling higher penetration of renewables.

The energy management system (EMS) optimises operation of the microgrid, taking into account parameters such as asset characteristics as well as weather forecasting to predict load and demand of the microgrid.