Hurricane Dorian struck down a great many power lines this past September, including the one which electrified my house, saddling me with the indignity of a small generator while some neighbours had to abandon their homes altogether, seeking warmth and water where the grid hadn’t yet failed. This was the case for hundreds of thousands of people across the Maritimes, except in Elmsdale, NS, where 10 homes proceeded much as they had before in spite of an unresponsive grid.
These 10 were part of a pilot project of Nova Scotia Power and Ontario based Opus One Solutions, the former supplying the hardware, and latter the software. With the installation of a Tesla Power Wall – a residential battery pack – in each home, together they formed something of a smart micro grid, an attempt by Nova Scotia Power to improve customer reliability and, in time, perhaps augment their grid outright.
This pilot was structured such that Nova Scotia Power continued to own these Tesla Power Walls for five years following their installation in 2017-2018, after which time the customer could either take ownership or have them removed. Likewise the electricity Nova Scotia Power shunted to these batteries remained their property until discharged into the houses themselves. The idea was to fill these batteries when there was little demand on the grid, then discharge them when the grid was struggling with peak demand, thus lightening the load. In this fashion, the Tesla Power Walls would ease the burdens of Nova Scotia’s electrical grid, carrying times of feats into times of famine.
During Dorian these 10 homes were without grid power 18 hours and 53 minutes, during which time they used the stored electricity of their Tesla Power Walls selectively, maintaining their fridges, internet connections, water pumps, perhaps even a television. When grid power was restored, these Tesla Power Walls had 30-40 per cent of their charge left over.
While small, this pilot project, which concluded in later 2019, provided proof of concept for the grid easing power of residential battery banks, customer reliability, and has inspired Nova Scotia Power to propose a bigger project, this time enfranchising 200 homes and businesses across the province with Tesla Power Walls. The buildings selected would be spread out this time; the project is presently before provincial regulators.
It’s a neat idea, harnessing an emerging technology to address the woes of our electrical grid, but of course my interest in the project has more to do with sustainability than reliability. By their very nature, renewable sources of power are intermittent, arriving in abundance when the wind is blowing or sun is shining, but leaving us in the lurch for much of the remainder, a reality which has stifled these technologies in some regions. The ability to store that renewable power when its arrives and spend it later would make all renewables considerably more practical in a province like Nova Scotia, where they’re sorely needed.
Nova Scotia uses a greater percentage of coal in its energy mix than any other province, 47.9 per cent according to Natural Resources Canada. Tally up the province’s renewables and they account for around 30 per cent, putting us far behind the majority of Canada. In a recent conversation with Nova Scotia Power, they professed to me a keen aware of the province’s goal of carbon neutrality by 2050, and said they are incorporating this goal into their plans for the near future. It seems a certainty that residential battery storage, such as those field tested in Elmsdale, will have a part to play in that renewable future, empowering us to embrace wind, tidal and solar above and beyond the convenience of modern coal. I only hope things play out as I’ve described, and that more of us won’t need generators next time a hurricane like Dorian complicates our day.
Zack Metcalfe is a freelance journalist, columnist and author active across the Maritimes.
Shown here is the “Tesla Powerpack” installed at the Elmsdale substation, another aspect of the pilot project which was not deployed during Hurricane Dorian because of downed power lines. (Rob Boone photo)