Embedded microgrids could change PV use

Energy research specialist Energeia says microgrids will empower consumers by giving them greater control over the cost, carbon intensity and reliability of their electricity supply - and, ultimately, the option of complete independence from the main grid.

The uptake of residential solar PV has already created an oversupply of power during daylight hours. Oversupply into the main grid can also cause inverters to automatically disconnect to protect power quality, and grid outages trigger solar PV systems to automatically disconnect for safety reasons.

These disconnections represent a loss of value to households which have invested in distributed generation and they will look for ways to protect their investment.

According to Energeia’s new report, Over the Edge: The Australian Outlook for Embedded Microgrids to 2027, a technical solution is already available: embedded microgrids.

Embedded microgrid solutions are a combination of local power source/s, battery storage, electrical interconnections, telecommunications and controls that together can deliver uninterrupted power when the main grid is shut down, switching back to the main grid when power is restored.

“We expect embedded microgrid technology to be commercially viable from around 2015,” said Energeia’s Managing Director Ezra Beeman.

With storage, consumers do not need to sell their surplus solar power to retailers; instead they can store it for their own use during peak pricing periods and earn a considerably higher return on their solar PV investment, Energeia says.

The sophisticated control systems associated with microgrids allow them to operate in ‘island mode’ using local sources, such as solar PV and combined heat and power (CHP), during an oversupply or outage event on the main grid.

Over the longer term, microgrids could provide a permanent alternative to grid-supplied electricity, with consumers increasingly choosing to go off the grid completely.

“Ultimately, we see microgrids offering customers an attractive alternative to mains supply, particularly for home businesses, where a loss of supply can have significant financial implications,” Beeman said.

The report is available here.