Creating a carbon neutral electricity grid

In recent years, a dramatic increase in electrical power generation from renewable energy sources has been observed in many countries. The grid-integration of customer-owned solar photovoltaics (PV) has been driven by government incentives and renewable energy rebates, including residential feed-in tariffs and the financial policy of net metering. However, new challenges arise in balancing the generation of electricity with variable demand at all times as traditional fossil fuel-fired generators are retired and replaced with intermittent renewable electricity sources.

This presentation considers ways to balance distributor and customer benefits of residential-scale battery storage co-located with solar PV, with a view of creating a carbon neutral electricity grid. Two issues that arise when accommodating significant residential-scale PV generation are addressed: the first is reverse power flow that leads to considerable voltage rise; the second corresponds to peak loads that occur infrequently, but potentially lead to the need for costly network augmentation when PV generation is unavailable. The benefits associated with addressing these two distributor issues are balanced with the benefit of scheduling battery storage to improve operational savings that accrue to customers.


Elizabeth L Ratnam received the BEng (Hons I) degree in Electrical Engineering in 2006, and the PhD degree in Electrical Engineering in 2016, all from the University of Newcastle, Australia. She subsequently held a research position with the Center for Energy Research at the University of California San Diego. During 2001–2012 she held various positions at Ausgrid, a utility that operates one of the largest electricity distribution networks in Australia. Her research interests lie in the areas of power systems and control theory. At the University of California Berkeley in the California Institute for Energy and Environment, Elizabeth is working as a postdoctoral scholar with Professor Alexandra von Meier, focusing on the demonstration of diagnostic and control algorithms with micro-synchrophasor data from electric utility distribution systems.

Date & time

11am–12pm 7 May 2018


Room:Seminar Room R214


Elizabeth Ratnam

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