Our forecasts contributed to supplying the Tahiti island with 100% renewable electricity for one hour on September 11

Our SteadyEye product provides solar forecasts for the next 30 minutes by monitoring sky and weather conditions above solar power plants using sky imagers. Our clients use it to anticipate very short-term solar electricity production variability.

Numerical Weather Prediction combined with real-time satellite imagery enables us to anticipate weather conditions and solar production in the coming hours and days but has some limitations in predicting clouds on small scales. This is particularly true over insular regions, even with high-resolution models (1-3km). For example, look at our intraday PV forecasts in Tahiti, which fail to capture the subgrid-scale variability of clouds in the afternoon sufficiently. Conversely, our network of 8 sky imagers installed around the island can provide very short-term actionable predictions.

EDT ENGIE uses both solutions to optimize the grid management of Tahiti Island and maximize solar production penetration into the grid currently composed of around 40MWp (>2,700 PV installations).

The company uses our intraday forecasts up to 12 hours ahead for energy dispatch scheduling (diesel gensets, hydropower, storage), and intra-hour forecasts up to 10 minutes ahead to manage spinning reserves in real-time. Last September 11, forecasts even helped EDT ENGIE supply the Tahitian grid with 100% renewable energy for one hour.

This performance was achieved during a test carried out throughout the commissioning of the ”Putu Uira” 15MW-16Mvar/10.4MWh Battery Energy Storage System (BESS).

Congratulations to the EDT ENGIE teams for achieving this historic first in the energy sector in Polynesia; we are glad to have contributed to this success!