Toshiba Energy Systems & Solutions Corporation (Toshiba ESS) and Next Kraftwerke Toshiba Corporation (TNK) have announced that they have achieved improved accuracy in renewable energy power generation forecasting through their Renewable Energy Aggregation Demonstration Project. The project was publicly facilitated by the Ministry of Economy, Trade and Industry, and aimed to showcase the feasibility of expanding renewable energy use and building a stable and efficient power system that utilizes highly unstable renewable energy sources.
The consortium, which includes 14 renewable energy aggregators and 9 collaborator companies, conducted demonstration experiments mainly from December last year through January this year. The use of storage batteries, along with the development of new forecasting methods, has led to improved accuracy in power generation forecasting and reduced imbalance risk.
Toshiba ESS, as the consortium leader, and TNK used REBSetTM, a renewable energy balancing system jointly developed by both companies, in the demonstration. Multiple methods were developed to reduce imbalance risk, including the use of storage batteries and intraday trading in the electricity market. The control method that utilizes storage batteries, where the real-time actual amount of renewable energy generation is reflected (feedback control method), was considered the most successful in reducing imbalance. The demonstration system on the cloud-controlled storage batteries successfully achieved an average of approximately 70% reduction of imbalance amount compared to the imbalance amount that would have occurred if storage batteries had not been used.
In the evaluation of renewable energy power generation forecasts, Toshiba ESS and Next Kraftwerke developed eight new forecasting methods for solar and wind power generation. They also increased the frequency of power generation forecasts and made forecasts at times closer to actual power generation. As a result, the minimum forecast error for solar was reduced to approximately 1.5% (Tokyo area/January) and for wind to approximately 11.8% (Tohoku area/January). In comparison, the forecast errors for solar and wind power in the same area last year were approximately 2.9% and 25.6%, respectively.
The profitability assessment of the aggregator confirmed that the new market transaction planning technology, which is part of REBSetTM, will result in greater revenues under the Feed-in Premium system than under the Feed-in-Tariff system. The demonstration also confirmed that creating a charge/discharge plan for storage batteries can increase aggregator income up to approximately three times. The suggested battery schedule charges renewable energy during times of high generation and low market prices, and discharges and sells electricity during times of low generation and high market prices. In months when electricity generation is high and the market price is at its lowest (0.01 yen/kWh), the results showed that the aggregator’s income could be increased up to approximately three times.
The Renewable Energy Aggregation Demonstration Project is a significant milestone in the development of a stable and efficient power system that utilizes renewable energy sources. Toshiba ESS and TNK will continue to develop control technologies using renewable energy power generation forecasting and storage batteries to solve issues and contribute to the realization of a stable and efficient power system that utilizes renewable energy.
The Renewable Energy Aggregation Demonstration Project has successfully improved the accuracy of renewable energy power generation forecasting through the use of storage batteries. This project is a significant step towards the realization of a stable and efficient power system that utilizes highly unstable renewable energy sources. The development of new forecasting methods and the implementation of storage batteries has reduced the imbalance risk, making renewable energy more reliable and attractive as a source of power. The project was conducted by a consortium of 14 renewable energy aggregators, including Toshiba ESS and Next Kraftwerke, and 9 collaborator companies, with the support of the Ministry of Economy, Trade and Industry. The success of this project is an important milestone in the expansion of renewable energy usage and sets an example for future initiatives.