Storage & Grids

The combination of rapidly evolving technologies and the trend towards decentralisation is demanding increasingly sophisticated commercial models. Simon Göß looks at some of the emerging solutions and considers the place of blockchain technology in tomorrow’s energy system.

Deploying battery storage at grid level is relatively uncharted territory, but a number of pioneers projects are now in the ground. Patrick Leslie and colleagues at RES, which built some of the first wave of storage projects, teases out the key technology, finance and regulatory lessons the industry can learn from these early experiences.

One of the claims made about large-scale storage coupled with solar is that it is difficult to justify from a business-case perspective. But evidence is already emerging from early projects that if done right, intelligent battery solutions are already competitive.

Plant control | SCADA technology enables PV plant owners to maintain their portfolios more efficiently and respond to increasingly stringent requirements from grid operators, yet avoid information overload. Sara Ver-Bruggen looks at the state of the art in SCADA systems as PV systems and fleets grow in size.

Grid investment | An ambitious plan is being drawn up to overhaul New York’s electric grid infrastructure, an exercise that some have priced at US$30 billion. Andy Colthorpe looks at the efforts underway to ensure renewables and energy storage are a central part of bringing the state’s power system into the modern age.

Off grid | Reducing the reliance on costly diesel-based power generation is high on the list of priorities for off-grid operators around the world. PV-hybrid systems alone can only go so far in meeting this need. The addition of storage can significantly alter this picture by increasing fuel savings and offsetting additional investment. Increasingly sound economics are already convincing circumspect off-grid operators such as mine owners who are starting to build the first large installations.

Battery technologies | The development of battery storage is seen as vital in the grid integration of increasing amounts of renewable power, but the various technologies present different advantages and limitations. Stephan Lux of Fraunhofer ISE weighs up the pros and cons of the main battery technologies in a range of applications.

Aggregation | Tesla’s much-hyped battery announcement in April raised important questions over what business models will drive the deployment of stationary battery storage. As Andy Colthorpe reports, one answer is the virtual power plant, in which residential and commercial battery systems are aggregated to provide grid services

The market outlook for utility-scale PV installations is very positive. These PV plants have the capability of supporting grid operation, and the ability to do this is being increasingly required in grid codes. Testing the capabilities of very large PV inverters, however, is demanding for laboratories. Gunter Arnold, Diana Craciun, Wolfram Heckmann and Nils Schäfer from Fraunhofer IWES discuss current developments and resulting challenges and address the gaps and diversity in testing guidelines and standardisation.

The combination of storage technology with larger scale solar projects is an emerging science. Andy Colthorpe speaks to PV power plant pioneers, Belectric, about a project completed at the end of 2014 to install battery storage at a utility-scale solar installation in Brandenburg.