Balancing the Grid: Canadian Energy Storage for Reliable Renewables

The sun goes down, and the wind doesn’t always blow. We need dependable energy storage solutions as solar and wind power more of our electrical grid. 

Canada uses various grid energy storage technologies today. Each has unique benefits, limitations, and capital and operating costs. A stable renewable energy future depends on more than one.

For a more in-depth look, check out the article by Lark Scientific Researcher Lucas Bettle,  Comparing Grid Energy Storage Technologies to Support Intermittent Renewable Energy Sources.

Energy Storage for a Renewable Grid

Energy storage systems (ESSs) balance supply and demand in real time with intermittent power sources.

Energy storage shifts the supply from peak generation times, like midday for solar panels, to demand peaks, like in the evening. Batteries work for about half of this demand globally.

Lithium-Ion and Sodium-Ion Batteries

• Lithium-ion batteries, particularly lithium iron phosphate (LFP), are most of what we use for short-duration energy storage technology. Decreasing costs, commercial maturity, and scalability make them an attractive solution. They are good for applications up to eight hours. Safety concerns, like fire risk, are still a challenge.

  
  

• Sodium-ion batteries are a low-cost alternative, at a 20 to 30% savings. They use more abundant materials, so projections are for a 10% share of new capacity in the next 5 years.

  

Alternative Battery Tech

Other battery technologies work to save energy to balance supply and demand.

• Vanadium redox flow batteries (VRFBs) work for long-duration storage. But they cost a lot upfront and ongoing, and vanadium is hard to get. They do last a long time and have stable performance over extended periods, making them a promising solution.

  
  

• Other batteries like iron-air and zinc-bromine are early in development for multi-day and seasonal storage. Low material costs and improved safety make them promising options.

  
  

Pumped Storage Hydropower

Pumped storage hydropower (PSH) is an efficient, mature tech. Water is pumped to an elevated reservoir to store energy, which is released through a hydroelectric generation station. Costs vary but are going down with larger systems.

Installations often last over 50 years, but you do need suitable geography, elevation, and water access. Long construction timelines and environmental permits are significant hurdles for new PSH development.

Other Storage Solutions

Compressed air energy storage (CAES) uses underground caverns or tanks to store pressurized air, later released to drive turbines. It’s a promising option for very long storage, but it needs the right geology and is still evolving in efficiency and permitting.

Hydrogen storage is gaining attention for seasonal or 100+ hour storage. Though efficient systems are still being developed, hydrogen has long-term potential. 

Also, thermal energy storage (TES), using heat instead of electricity, is ideal for industrial and solar applications.

Behind-the-Meter Battery Storage

Behind-the-meter (BTM) battery systems are used at homes and businesses with rooftop solar or for backup power.

A large network of BTM systems becomes a virtual power plant (VPP) like they have already in California and Germany.

Grid Energy Storage Solutions Today and for the Future

• Lithium-ion batteries balance cost and performance for short-duration storage for quick response.

  
  

• Flow batteries and thermal storage show promise for medium durations despite higher upfront costs.

  
  

• For long-duration storage, pumped storage hydropower is still the most cost-effective option, but hydrogen and compressed air energy storage are possible future alternatives.

  
  

No one tech can meet all of the energy storage requirements of a renewable grid in Canada. Applying each option based on any given application’s cost, duration, and scalability is key to achieving a resilient grid with high intermittent renewable adoption.