In any market, the key to success is matching supply with demand. Oversupply, and resources are wasted; undersupply, and increased prices frustrate consumers. Market management is a delicate balancing act with the electricity grid. Unlike with water or natural gas, electricity cannot be stored—at least not in large quantities—so supply must always equal demand.
Energy storage has often been referred to as the smart grid’s Holy Grail. It offers grid stabilization and the ability to mitigate the inherent intermittent nature of renewable resources. It can provide regulation services to the grid and reduce (perhaps, over the long run, even eliminate) the need to export energy at a loss.
There will be no one magic bullet as solutions will take many forms and bring diverse attributes to the grid. We will likely see a network of complementary technologies deployed at various locations, each solving a unique set of challenges. The Toronto-based MaRS Discovery District works with several companies to help commercialize solutions and open export markets. Canada is poised to be a world leader when it comes to energy-storage technologies, and exploiting international markets will be essential.
The global market for energy storage was $1.5 billion in 2010 and is expected to grow to $35 billion by 2021, based on a 100-times increase in capacity. Ontario’s Long-Term Energy Plan calls for an initial 50 megawatts (MW) of energy-storage capacity by the end of 2014 with more to follow. Other jurisdictions around the world, including Germany, Japan, and California, are also prioritizing energy storage. Germany has allocated €30 million for solar storage incentives, and California has called for 1,325 MW of storage capacity by 2020.
There are many ways to categorize energy storage technologies: duration, efficiency, cost, and application, with solutions satisfying a combination of these factors. For grid-scale storage, power-to-gas, pumped hydro, and compressed air are able to accommodate the necessary capacities and also offer longer durations. Flywheels offer grid-balancing characteristics and shorter-duration storage, on the order of milliseconds to minutes. Smaller-scale systems servicing a community can often be achieved with batteries and tend to be optimized for a 24-hour demand cycle. Technologies are scalable, which is important for micro-grids in remote communities, mines, and islands where capacities and durations are longer than community scale, but are significantly smaller than grid scale.
Power-to-gas is one of the most promising technology options for grid scale energy storage, combining attributes of different infrastructure and linking the electrical grid and natural gas networks. In 2013, Germany opened the inaugural commercial power-to-gas unit with 2 MW capacity in Falkenhagen, Germany. Here, wind provides power for Mississauga-based Hydrogenics’ hydrolysis equipment, converting water into hydrogen, which is then added to the natural gas system. Hydrogenics has also partnered with Enbridge to develop utility-scale energy storage in North America.
Hydrostor is another Canadian success story in international markets. Off-peak electricity is used to pump air into chambers deep underwater. During peak demand, air is released, generating electricity with 70-per-cent efficiency. Their value proposition works for shores with rapid drop offs and low water temperatures like those found in the Caribbean Islands and Lake Ontario, where they are currently conducting a pilot with Toronto Hydro. Unlike power-to-gas, Hydrostor’s technology doesn’t offer seasonal storage; however, it can dramatically reduce stress during peak periods.
As a complement to large-capacity storage options, distributed storage employs multiple smaller systems deployed throughout the grid. Systems can be located in close proximity to the generation sources, in the case of solar panels or wind turbines, or near the point of consumption, in communities or buildings. Toronto-based eCamion has designed a lithium-ion battery system that is modular, employs intelligence controls, and is able to interact with building management systems, on-site generation, and the smart grid. Electrovaya, also an Ontario company, has commercialized their advanced battery technology with improved energy density requiring less space for the same storage capacity. Its technology also has applications in clean transportation and the health-care markets. Electrovaya and eCamion’s systems offer flexibility during peak demand periods, providing reliable electricity and mitigating blackouts.
For shorter-duration storage, turn to flywheels, which offer improved power quality and lower costs by accurately balancing energy generation and power usage. Mississauga, Ontario’s Temporal Power is a world leader, manufacturing the highest-energy flywheel technologies available today, balancing the short-term intermittency of renewable resources, and absorbing and inserting power as needed. Its technology is also applicable on micro-grids by optimizing generators and allowing integration of renewables. Traditional generators can take several minutes to adjust to grid demand while Temporal Power’s flywheel can ramp up in milliseconds, delivering power precisely when it’s needed. They are currently conducting a pilot with Hydro One as an alternative grid-balancing technology.
In order for energy storage to be a linchpin solution, governments and industries need to break down barriers, including market rules that currently penalize storage applications. The current regulatory framework has global adjustment, debt retirement, uplifts, and transmission and distribution costs charged twice—once when energy is captured and again by the end user. The complexity of the electricity system with generators, utilities, regulatory boards, and consumer groups hinder the ability to make changes. Benefits of energy storage are difficult to monetize for multiple stakeholders, and those inevitably benefiting are not necessarily the decision makers.
One innovative Canadian company is working around some of these challenges by using storage that already exists on the grid. Flexibility around industrial systems and processes offer a form of energy storage that, when amalgamated, offers significant capacity. Enbala Power Networks is using their demand response system to increase grid reliability while adding a new revenue stream to commercial, industrial, and institutional electricity users. It does this by responding to small and frequent changes in electricity consumption and generator output in order to maintain a constant balance.
The Ontario Independent Electricity System Operator launched a grid balance initiative in 2013 with Sunnybrook Health Sciences Centre already employing Enbala’s technology. “Large electricity users are such a valuable resource to our electricity power system,” said Ron Dizy, president and CEO of Enbala. “By intelligently managing the flexibility in when and how they use power, we’re able to deliver value back to the grid in a number of ways—while generating a new revenue stream for connected users.”
“Innovation is a cornerstone of health care delivery—and that includes the way we manage our facilities,” said Michael Young, executive VP and chief administrative officer at the Sunnybrook Health Sciences Centre. “This initiative provides a new opportunity for Sunnybrook to contribute to the overall reliability of Ontario’s power system and generate new revenue to help sustain our services—all without impacting the comfort of our patients or our employees.”
If commercializing world-leading energy-storage technologies is a priority, we need to reduce congestion and deferral of capital to help Canada’s companies demonstrate their technologies and sell into international markets. Energy Storage Ontario brings together innovative companies with other stakeholders, including project developers, utilities, research groups, energy consultants, and power generators, to break down barriers and implement energy storage to the provincial grid.
With international interest and energy storage highlighted as a focus area in long-term global energy strategies, the province will likely see the development of recovery mechanisms removing barriers and enabling people to meet short- and long-term deployment objectives.
Jennifer Stoneburgh is an associate with the MaRS Discovery District in Toronto in cleantech, physical sciences, and advanced materials.