In the last year and a half, Accenture Technology Lab’s smart grid team has been working with researchers from Zhejiang University on innovative micro-grid, multi-energy optimal scheduling solutions.
Micro-grid is a small scale energy supply system that is self-controlled, protected and managed. From the bulk power grid’s view, a micro-grid can be regarded as a controllable load or schedulable generation unit. There have been micro-grid pilot projects around the world. But most of these projects run in an island operation mode in remote or isolated environments, such as military bases, islands and rural areas that lack a connection to the bulk power grid. In our view, the full micro-grid business benefit cannot be realized unless there are solutions that a micro-grid can provide, including multi-energy services for an urban load center and the ability to run in a grid-connected operation mode.
Through collaborative R&D work, Accenture Technology Labs and Zhejiang University have developed an innovative solution to maximize the benefits provided by a micro-grid. This study focuses on the application of a micro-grid on urban load centers to meet customers’ multi-energy demands locally. Examples include providing electricity and cooling energy to high-technology parks, commercial buildings and residential areas.
The micro-grid solution we have developed can supply both cooling and electrical energy. It includes several typical micro-grid components: wind power, photovoltaic (PV), a combined cooling/heating and power (CCHP) unit, an ice storage air-conditioner, and an energy storage device.
As renewable energy resources, wind power and PV provide unstable electrical power. A CCHP unit provides cooling energy and electrical energy. An ice storage air-conditioner consumes electricity in the valley hours by making ice; in the peak hours, it releases the cooling energy stored in the ice tank to meet customers’ cooling energy demands. (Note: CCHPs and ice-storage air conditioners work together in a coupled process due to their working modes.) Finally, a storage device stores the electricity when the micro-grid has redundant energy or when there is power available from the main grid during valley hours. It is mainly used for smoothing the output changes of the renewable energy output and the load variations in the real-time dispatching.
The objective of the micro-grid study is to meet customers’ multi-energy demands by finding the optimal energy schedules for each micro-grid component while achieving the minimum total operation cost. Through the R&D collaboration, we built a multi-energy scheduling optimization model and developed an integrated scheduling algorithm based on a multi-time scale. It includes two parts: day-ahead scheduling and a real-time dispatching algorithm. This approach can help a micro-grid system operator achieve an optimal scheduling plan and operation strategy.
This R&D collaboration has produced a patent filed to the State Intellectual Property Office of the People’s Republic of China (PRC), a paper submitted to IEEE Power and Energy Society (PES) transaction, and a prototype of micro-grid, multi-energy optimization scheduling being demonstrated to Accenture’s clients.
Accenture Technology Labs is continuing the R&D collaboration with Zhejiang University in the micro-grid area, with a current focus on developing an optimal micro-grid planning solution that targets planning how a micro-grid supplies the multi-type energy demands by utilizing wind power, solar power, CCHPs, ice-storage air-conditioners and energy storage devices.