Energy Storage Overview

Utilities have the challenging task of estimating energy usage. This can be done by looking at historical information, usually citing last year’s information. Then, they have to consider recent weather trends, climate change and other information.  All this information is entered into complex equations that determine what we might use today.  Confusing, maybe, complicated, YES!  To boot, in Canada, this is done every day, every hour.

Now, the grid needs to make sure there is enough electricity to meet the needs of their customers. Some technologies can be turned off quickly, like solar, some technologies take a lot longer to turn off like nuclear or fossil fuels. The balance act is making sure there is just the right amount. Too much causes issues, too little causes brownouts or blackouts.

Energy storage is accomplished by devices or physical media that store energy to perform useful processes at a later time. A device that stores energy is sometimes called an accumulator. Many forms of energy produce useful work, heating or cooling to meet societal needs.
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So, utilities have been trying to store energy for a long time.  Now, this technology, in many forms, is ready for prime time; from pumped storage to all types of batteries to compressed air and hydrogen ending with Flywheels.  There are many solutions in the research phase as well.

There has been a real shift in public exposure to energy storage and its use in our energy mix. Below are a list of creditable sources that discuss their opinions of what energy storage is and what the value is to our electricity grids reliability and resiliency. 

Overall, Energy Storage is going to become an important part of the Electricity Grid in Ontario, from a supply, transmission and distribution point of view.  The public exposure this sector is receiving is causing stakeholders like local distribution companies, end-users and regulators to assess and evaluate its use in Ontario.

From Independent Electricity System Operators*:

Unlike other forms of energy, electricity could not be easily stored in large quantities. As a result, the electricity system has historically operated on a "just-in-time" basis − with decisions about electricity production based on real-time demand and the availability of transmission to deliver it.

This paradigm is now changing with the emergence of new energy storage technologies, which allow electricity to be captured and dispatched to the grid whenever required. Storage can also benefit the system in the following ways:

  • Smoothing out fluctuations of solar and wind resources, bringing added stability to the electricity system
  • Easing points of congestion in transmission and distribution networks by temporarily absorbing surges and excess power flow, allowing utilities to defer, or even avoid, expensive system upgrades
  • Absorbing surplus baseload generation when the output from renewable energy sources is high during off-peak hours


From Ontario’s Ministry of Energy Long Term Energy Plan:

  • Ontario’s energy sector is an innovation leader. The government will seek to expand the Smart Grid Fund and build on previous success. The Smart Grid Fund has created more than 600 jobs and supported 11 projects developing innovative technologies.
  • The government intends to initiate work, on a priority basis, to address regulatory barriers that limit the ability of energy storage technologies to compete in Ontario’s electricity market.
  • By the end of 2014, the government will include storage technologies in our procurement process, starting with 50 MW and assessing additional engagement on an ongoing basis.
  • The new competitive procurement process for renewable energy projects larger than 500 kW will also provide an opportunity to consider proposals that integrate energy storage with renewable energy generation.