Opinion: Canada Must Address Future Energy Storage Needs

The website of the Energy Storage Alliance in Australia is worth looking at.  A very explicit and strong understanding that energy storage is one of the key factors in decarbonization and integration of more renewables is well expressed.  Here in Canada, we have additional needs (e.g. heat needs in the winter with potential heat storage on a seasonal and large-scale basis…) that make our energy storage spectrum somewhat different, but the impacts and concerns are similar: without strong action on large-scale energy storage, we will stumble along with continued inefficiencies at the cost of climate change progress and required grid modifications.

Canada is not without a similar organization, Energy Storage Canada, but it seems somewhat less active than the Australian counterpart. 

The report Removing Obstacles for Storage Resources in Ontario from the Independent Electricity System Operators  (IESO) addresses some of the issues in energy storage, but there are additional dimensions.  An important dimension is cost-effective small-scale energy storage to meet the needs between the individual homeowner scale and the 1000 MW grid scale.  

Canada is more fortunate than Australia in terms of the wide-spread availability of hydroelectricity.  Because hydro power is relatively easy to ramp up and down, in combination with coal fired and nuclear power plants providing “base load”, it has served and continues to serve a critically important role in our national grids in terms of provision of base power as well as meeting large-scale variable demand needs at a time-scale from minutes to months.

However, as we slowly transition toward a roads-based transportation system that is not based on fossil fuels, we will need far more electrical power, and this means that energy storage needs will also rise.  Where will this additional electrical power at a grid scale come from?  Here are the alternatives, assuming that supply management is not going to be undertaken, to avoid the high prices for the consumer that supply management brings:

  • More nuclear power stations (base load power with output at a constant level at a time scales of weeks)

  • More natural gas combined cycle turbines (a fossil fuel, but non-polluting and far more efficient than solid coal)

  • More hydro power (with attendant flooding of valleys)

  • More wind and solar power (large-scale storage is vital if this is to grow to a large fraction of our power sources)

  • More geothermal energy (enhanced geothermal systems, but these remain far in the future at a grid scale)

Which do you prefer?  In what proportions?  Some are inherently large scale, hydro and nuclear specifically (generally, >100 MW)), natural gas and geothermal energy can be considered scalable to meet intermediate needs (1-100 MW), and irregular and variable wind and solar power, which accordingly need grid-scale storage capabilities.  Geographic constraints are important.  For example, as much as we might wish otherwise, the sun doesn’t shine and the wind doesn’t blow enough in the winter months in Northern Canada to serve as a large-scale power source.  The sunniest spot in Canada is southern Saskatchewan, but over 50% of Canada’s population lies within 150 km of the highway from Quebec city to Windsor.  The best wind in Canada (steadiest and strongest) is probably in the Gulf of St Lawrence, and the proponents of green power in Vancouver and Toronto are far away, and do not want wind farms in front of their (energy inefficient) picture windows.  

Whatever we choose, if renewables are to be a significant part of this grid-scale supply option array (>20%), large-scale storage is needed.  Because of their huge environmental impact (chemicals, metals, recycling…) if implemented at a vast scale, as well as their cost per kWh, the solution is not likely to be batteries at grid-scale in the form of static battery farms.  This leaves the following options for grid-scale energy storage, each of which has advantages and disadvantages in terms of environmental impact, geographical viability (pumped hydro). 

  • Distributed batteries in the future fleet of EVs can serve as a grid-scale storage base, with appropriate technology and contracts with electric vehicle owners.

  • Pumped hydro, with geographical and social constraints.

  • Compressed air energy storage, with some geographical constraints for large-scale projects.

  • Generation of fuels from non-fossil sources, such as hydrogen from excess electricity during periods of low demand, which is unlikely to meet the needs of the transportation sector for many decades.

Other approaches can be used at a small scale, such as underground heat storage (geothermal heat pump systems at various scales), better home construction standards (an energy storage approach, or at least a thermal energy retention approach), and local implementation of renewables at the scale of homes to large communities.  However, many of these use connectivity to “the grid” as their “insurance policy” against supply interruptions or prolonged periods of low supply.   So, someone still has to pay for the grid, if you use it as an insurance policy by staying connected. 

My view is that we should be promoting environmentally benign storage of energy at all scales as our insurance policy, as we move toward decarbonization of our power sources and our ground-based transportation fleet…

Amicalement, Sincerely yours

MB Dusseault, UWaterloo