Canada needs a massive battery

The federal government is developing Clean Energy Regulations (CER) to help move the electrical grid to net-zero emissions. The regulations, among other measures, will encourage adding more renewable energy to the grid, which will eventually replace coal and natural gas electricity generation in Canada.

In light of the recent hydrogen deal Canada signed with Germany, investors are looking at renewable energy to produce green hydrogen in Canada. This is preferable to blue hydrogen, which requires costly and unproven carbon capture and storage, but is it more efficient to use renewable energy infrastructure to power the electrical grid, at least until net-zero power generation is reached?

One of the most common arguments against using the cheapest sources of clean energy (wind and solar) to power the electrical grid is that renewables are intermittent, and we will always need natural gas power plants to generate baseload power for the grid. Why even bother with these unpredictable energy sources?

This narrative is changing as power storage solutions are successfully being added to the North American grid. Grid storage is essentially a massive battery that stores excess energy when the sun is shining and the wind is blowing. When renewable energy output is low, the stored power is used to keep the lights on, the computers running and the electric vehicles charging.

In June 2021, Enmax announced it was the first utility in Canada to introduce a hybrid electric gas turbine. The Crossfield plant north of Calgary is a peaking facility, which means it is designed to provide power quickly to the grid, within 10 minutes, in order to meet unexpected changes in demand.

A baseload power plant provides consistent power to meet the average demand on any given day. Renewable energy adds to the electrical grid, allowing coal or natural gas generators to run at lower capacity, thereby reducing greenhouse gas emissions (GHGs). But demand can increase suddenly, such as when air conditioning kicks in across the province on a hot summer afternoon, and that’s when peaking plants respond to provide the extra power.

To be able to meet the surge in energy demand within 10 minutes, the peaking plant must have the gas turbines idling even when the power isn’t needed. Otherwise, they’re too slow to start up. Enmax estimated this idling released 45,000 tonnes of GHG emissions annually. By adding a grid-scale lithium ion battery to the system, the gas generators can remain off and the battery will supply the grid long enough for the peaking turbines to be fired up when needed.

This is a great example of how grid storage solutions are being used to reduce emissions, as well as operating costs. In addition to operating cost savings from cutting natural gas consumption due to idling, the GHG reductions amount to a savings of $2.25 million per year at a carbon price of $50/tonne and $7.65 million per year at $170/tonne. Payback on the initial investment of $14.6 million on grid storage will be easily achieved in less than 10 years.

Lithium ion storage solutions are available from multinational companies like Eaton and General Electric, but there are smaller Canadian players, such as Microgreen in Markham, Ont., looking to capitalize on the growing demand for grid storage. Typically, the battery banks, inverter, cooling, and control system are all housed in a single 20- to 40-foot shipping container, which simplifies transport and installation. These containers can be combined to create 10 to 20 megawatts of storage. The largest battery system in California can provide 400MW of power for up to four hours, an hourly output equivalent to a large natural gas power plant.

Canada’s Hydrostor Inc. uses a unique method of storing energy via compressed air. Electricity from the grid is used to pump compressed air into an underground cavern filled with water. The air displaces the water and forces it up to a reservoir at the surface that is filled when the caverns are fully charged with air. When power needs to be generated, the process reverses, with the compressed air driving turbines to generate electricity. This system can provide 24 hours of power generation and has a 50-year operating life. In this scenario, an appropriately sized solar farm in conjunction with a Hydrostor system could provide around-the-clock power, fully replacing baseload power from coal or natural gas generators.

Vancouver-based Zinc8 Energy Solutions is developing a novel zinc air battery that can be scaled from a storage capacity of four hours to more than 24 hours simply by increasing the size of the zinc storage unit. Renewable or grid power is used to regenerate zinc particles, which are captured in the storage unit. A fuel power stack uses the stored zinc to generate electricity when supply is needed for the grid. For long-term storage, the zinc air technology is significantly less expensive than lithium ion storage.

The commercialization of grid storage technology is well underway, but as with solar panels and wind turbines, costs will continue to drop as production scales up and technology improves. New grid storage technologies like iron flow batteries and solid hydrogen could provide even lower-cost solutions in the future, although commercialization of these technologies is probably several years away. Wind and solar power generation costs have dropped to the point where they are now competitive with natural gas. As the price of carbon increases, renewable generation will be more profitable and less prone to price fluctuations and supply problems.

As storage capacity increases and costs drop, the demand for fossil fuel power generation will decline accordingly. These changes to the electricity system will not happen overnight, but they will continue to roll out as the world struggles to decarbonize and decouple energy supply from undesirable producers. Europeans dependent on Russian natural gas are certainly lamenting that they don’t have enough systems like these in place.

Rob Miller is a retired systems engineer, formerly with General Dynamics Canada, who now volunteers with the Calgary Climate Hub and writes on behalf of Eco-Elders for Climate Action. As a climate activist, he works to stop old-growth logging in B.C., reject coal mining on Alberta’s eastern slopes, facilitate community involvement in urban afforestation, and advocate for renewable energy. Miller uses a “systems-thinking” approach to learn, understand, and defend the ecosystems that are under threat by climate change and unrestrained resource development. He lives in Calgary.