There have been many discussions about whether micro or macro grids will be the biggest key in the renewable energy race. Some argue that macro grids are best, as having a vast array of high voltage transmission lines that can carry electricity from sunny Vancouver to meet the needs of those living in Montreal at nighttime in the dark during the winter. Others stand by microgrids being the better choice as they avoid the expense of building more transmission lines and being reliant on the grid as a whole.
So, which is best and what is a macro grid? In this article, we will cover what they are and how they could be helpful within Canada.
Microgrid vs Macro grid: What’s the difference?
The difference between a microgrid and a macro grid isn’t difficult to explain or understand – a grid-connected microgrid normally operates connected to and synchronous with the traditional wide area synchronous grid (macro grid) but is able to disconnect from the interconnected grid and function autonomously in ‘island mode’ as it’s called, as technical or economic conditions dictate.
Essentially, a microgrid boiled down to the definition is that it can disconnect from the main grid and function on its own without needing to be permanently attached to the grid and working as such. It is a system of energy sources, energy storage, and energy consumers that can operate completely independently from the traditional centralized power grid (which is the macro grid) when it is set to ‘island mode’.
Macro grids may be recognized more as the mega grid or hybrid grid, as the configuration goes by many names otherwise. An easy way to think of a macro grid is to think of it as an overlay that pulls together existing grids and makes it simpler to move power between them, making it easier to receive and use power between areas that may get more renewable energy. For example, sunny west coast renewable energy power may be sent much easier through the macro grid over to the east coast hit by storms or during the night while it’s dark and they don’t have the energy currently due to various reasoning.
It essentially helps move renewable power around the country faster and easier, especially towards areas and communities that otherwise may not have access to renewable energy/electricity.
How can macro grids be useful in Canada?
Climate change has already shown the beginning of extreme events and conditions that we currently may not be set to handle. A disaster in Texas showed that electricity utilities need to prepare for extreme events in the future – and not just in America.
Hotter summers and colder winters across Canada have been putting more strain on the electricity utilities than ever with air conditioning units and other such appliances pulling energy and electricity more than ever before. More intense storms, higher wind speeds, droughts, and heatwaves that will be ongoing will only continue to hinder the systems.
If the electricity sector adapts to the changing climate and being a central role can help to mitigate climate change and reduce greenhouse gas emissions as it does so. Zero-emissions electricity can be used to electrify transportation, industry, and heating to help offset and reduce emissions in those sectors as well. Enhancing and going forward with the long-distance transmission is viewed as a cost-effective way to enable clean and reliable power grids and lower the cost while hitting target goals for climate change.
Failures across the electricity grid can be catastrophic for Canadian cities and communities across the country if they were to happen, and choosing to strengthen the reliability of current electricity while also ensuring a greener option and reducing our carbon footprint is ideal for everyone. It can be looked at essentially as insurance for climate extremes and additional security just in case the worst does happen. The Texas incident showed a glaring issue that could happen here as well – the power outages due to extreme conditions lead to failures across all forms of power supply and the state lost its capacity to generate electricity from all sources such as coal, natural gas, nuclear and wind – simultaneously.
It also lacked transmission connections to other electricity systems that could have helped bolster supply. The long-distance transmission offers the opportunity to do so, which in Canada is perhaps even more important as the entire country has far more ‘open spaces’ and fewer people. Communities are smaller and being able to ensure that they have power just as well as capital cities, especially with the weather, dark winter months, and severe storms is something that should be considered a good idea for everyone.
The Quebec ice storm in 1998 for example left nearly 4 million people including Ontario and New Brunswick citizens without power. That can easily happen again, if not with worse results and issues later on as the climate changes for the worst. More transmission links can help bolster reliability and improve resilience by coordinating supply across regions. Well-connected grids that are larger than areas disrupted by storms and outages can be used more reliably during climate extremes.
How does it help mitigate climate change?
More transmission can lead to and play a role in mitigating climate change. Studies have shown that building large transmission grids that allow for greater shares of the renewable power and other renewables on the grid can ultimately lower the overall cost of electricity and that by itself can help to lower greenhouse gas emissions in Canada’s electricity sector alone.
Reducing greenhouse gas emissions is lower when enhanced or new transmission links can be built between provinces. Most of the transmission values in the building scenarios come from linking high-quality solar and wind resources that are already being utilized with zero-emissions generation that produces electricity on demand when it is needed. Canada’s system is dominated by hydroelectricity but most of it is spaced out and placed in British Columbia, Manitoba, Ontario, Quebec, and Newfoundland and Labrador. In the west, Alberta and Saskatchewan have perfect locations for building new low-cost wind and solar farms that can be used for enhanced interprovincial transmission.
Both provinces (and others) could, for example, receive backup power from BC and Manitoba when there is no wind or the sun isn’t shining. Vice versa when the prairies are abundant with sun and wind and the flow of low-cost energy could help Manitoba and BC the opportunity to manage their hydro reservoir levels as well. All provinces would benefit from helping each other out and trading with each other if we create the infrastructure to make the trades possible would be monumental to not only help battle climate change but helps to create a more reliable and stable power source across the country, especially during disasters and emergencies when it is needed most.
If Canada can address the barriers and costs it takes to facilitate macro grids, it could lead to an advantageous positive across the country and provinces for energy and climate change reduction. Lower costs and zero emissions are also incredibly beneficial as consumers as well as taking the pressure off our overworked electricity grids as they currently stand.
