Toronto Hydro has unveiled a new way of locating battery storage closer to the edge, with a pole-mounted unit developed by Ryerson University and eCamion – which promises to significantly reduces stress on the utility infrastructure, extending its lifespan. The pilot was funded through a Ryerson grant, is showing very positive results in initial stages – meaning a likely expansion to 10 other transformer poles in Toronto.
Toronto Hydro is trailing the technology to explore whether the battery will be able to extend the lifespan of its transformer equipment – potentially reducing its capex costs. The system works by allowing a stressed transformer to divert excess power into the battery – storing it for later use, and preventing the transformer from overheating and failing due to excessive voltage.
Installing a battery at the network edge also enables energy time-shifting, storing electricity during off-peak hours, and then releasing it when there is sufficient demand. The battery can also act as a source of temporary backup power during outages – something that utilities in areas that suffer from extreme weather will be interested in.
eCamion CEO, Carmine Pizzurro, told Riot that adding battery storage to a transformer makes most sense at points on the network where there is a high duty cycle. Transformers in high duty cycle areas have a much greater risk of unexpectedly failing – which cause expensive unplanned outages, which can risk lives and lose customers. A transformer that fails under high voltage stress condition, can also potentially catch fire or explode.
Toronto Hydro had found that, in certain problem spots, the lifespan of a transformer was as low as 2-3 years. In an area where the duty cycle is lower, the utility would expect to be replacing a transformer after 20 plus years.
The climate in Toronto presents further challenges as the city experiences extreme temperature both in summer and winter, adding to the stress on the infrastructure. The growing popularity of electric vehicles has also increased the electricity demand, putting more stress on the distribution network.
Toronto Hydro is the largest electricity distribution company in Canada, serving approximately 756,000 customers in the Toronto area. It uses 3 phase transformers to step down electricity from the transmission network to its customers – moving from the very high voltages needed to transport electricity from the power stations into the kinds of voltages that are required in homes.
If the pilot continues to prove successful then Toronto has some 175,000 transformer poles across the city, meaning the product has a high potential to scale in the area. Pizzurro was confident that Toronto Hydro will be rolling out the project to an additional 10 other transformer points, as an extension of the trial.
Adding storage to this point of the network also makes the grid better prepared for future growth in distributed renewable energy. An increasing number of individuals are adding rooftop solar to their properties. This creates an up-flow of electricity to the transformer adding extra stress to it. This is compounded by rooftop solar producing its peak energy during the middle of the day when households near to the transformer are demanding less electricity.
The batteries used in the project are Lithium-titanate, an extremely high quality type of battery cell chemistry that has an extremely long battery life cycle, fast charging times, and high safety specs. Pizzurro assured Riot that the batteries were premium products, and can deal with 30 to 100 times the current peak of ordinary Lithium batteries.
Pizzurro said the project was born out of meeting Toronto Hydro staff at various events, and that eCamion led on the design and manufacture front of this project. The project was funded by Ontario’s Smart Grid Fund, which helps companies in the smart grid industry to test their grid solutions.
Pizzurro told us that eCamion would also be involved in another project to build 50 fast charging EV stations with battery storage. To date, fast charging stations have been reliant on local transformer and substation being able to service some 600 volts of power. In suburban towns, such high voltage electricity servicing is not available, and so fast charging is not possible. The current work around to this issue is to pay extra to a utility for the increased capacity in an area – this solution works out as less cost effective than the fast charging plus storage design.
The addition of battery storage means that extra electricity produced on the network can be stored at the charging point, before being pushed out to an electric vehicle at a rate high enough to achieve fast charging.