The biggest barrier to microgrids

Greg Allen (2)

While Australia’s energy industry has become comfortable with microgrid technologies and many states are already experiencing benefits, it’s the establishment of viable business cases for different applications that is the main barrier to their uptake. In the lead-up to his presentation at the 2018 Australian Energy Storage Conference and Exhibition, Greg Allen, executive general manager, Carnegie Clean Energy said using battery storage in microgrid projects, industry challenges and the integration of renewables.

Allen has 20 years’ experience in engineering, specifically in business development and operational experience in the industrial plant and equipment, and solar industries. Allen oversees all the company’s commercialisation activities

The company is undertaking several microgrid projects, including the Garden Island Microgrid, a network-connected microgrid that integrates existing diesel generation and grid infrastructure with a 2MW solar PV farm and 2MW/0.5MWh battery energy storage; and the CSIRO’s Square Kilometre Array Pathfinder (ASKAP), an off-grid 1.6MWp solar facility in combination with 2.6MWh battery energy storage system capable of diesel off functionality.

Allen said microgrids are having a major impact on the sector by improving reliability, efficiency and supporting aging infrastructure.

“They will increase the penetration of renewable energy, that’s a given, but without compromising quality and reliability of supply,” he said. “So they’ll offer those alternatives, we’ll get higher levels of renewable energy penetration with the same, if not better, levels of quality and reliability supply.

“It is an alternative to replacing aging assets, and it’ll make sense at the fringes of the grid first. As the cost of the systems come down, it’ll bring in the length of line to be replaced, or the amount of transformers and substations to be upgraded.”

Allen said the biggest challenge for the development and implementation of microgrids is actually establishing a viable business case for different applications, because the viability of a business case is dependent on the difference between average and peak demand in that location.

“Generally, in terms of economic drivers, there needs to be something more than just reducing the cost of supply of electricity,” he said. “It needs something around a reliability improvement that ultimately has a cost, but it’s very hard to sometimes put a value on the cost of that reliability improvement.

“Microgrids have been out there on remote cattle stations throughout Australia in regional towns for many years as just a pure diesel system. The next step is making them high penetration renewable microgrids, and that’s all about justifying the business case to increase the penetration, or start putting renewables on and then increasing those.”

Allen also believes that while microgrid technology is established in the industry, it’s other factors such as regulation that has the potential to affect implementation.

“The technologies all exist and we’re comfortable with those technologies. Integrating the technologies, managing the risk of integrating technologies of the various sources of generation on the systems, is all within engineering capability, and the products exist to do that. But one of the key challenges is actually coming up with the right configuration that essentially makes business sense, as opposed to technical sense.”

Resilient microgrids have existed for a while now with a lot of towns in Western Australia, South Australia, Northern Territory and Queensland all operated by diesel or fossil fuel microgrid systems. Allen said the way forward is now integrating high levels of renewable energy.

“The technology advances that have been happening, and that is obviously the cost down on solar, the advances and availability of solar, and readily available solar technologies, have started to move that forward,” said Allen.

“Battery energy storage technologies and the associated microgrid control architecture enables you to automatically dispatch and make decisions on which piece of kit is the best, which generation kit is best to dispatch at that time, and match the load in the most efficient and stable way.

“The final piece is then managing the electrical protection aspects of those systems so that you can provide the same level of safety and protection as has been afforded to those customers using traditional fossil fuel technologies. This does require some rethinking on how you provide that electrical protection, given the generation sources are moving from reciprocating or rotating machinery, to inverter-based technologies.”