This article was initially published in Interior Wellness magazine’s Spring 2014 issue (pg 17). It is still relevant; many people are still learning about how renewable energy systems work.
Do you know the difference between the types of renewable energy systems?
In the renewable energy business, we often refer to “on-grid” or off-grid”. These terms refer to whether or not the site receives power from a utility. If your home, cottage or business is supplied with electricity supplied by BC Hydro, Fortis BC or another utility, it is “on-grid”.
A renewable energy system can be one of 3 general types
“Off-grid”, a stand-alone power system using a sun, wind and/or water source plus batteries and fossil-fueled generator.
“On-grid”, feeding the energy it provides to your home and as well as back into the utility grid.
“On-grid with battery and/or generator back-up”, which feeds into the grid but has the added capability to supply back-up power if the grid goes down.
We can also create community power systems that can be “off-grid” and can form their own independent ‘micro’ grid supplying multiple homes or businesses.
Shouldn’t we get off the grid?
Many people want to “get off the grid” and think that this will help the environment. What they may not realize is that to be off-grid, they [almost always unless they have an exceptional combination of natural resources] must have a battery bank and fueled generator to maintain their batteries and provide back-up power. Batteries, while recyclable, are energy intensive to produce and currently form a significant portion of the investment in an off grid power system. Fuel also costs money and the environment.
The Value of being Grid-tied:
In other parts of the world, where the utility is coal-fired, one could argue for the green value of going off-grid, but here in BC, while we can choose to do that for independence or due to high utility interconnection costs, it cannot provide a smaller carbon footprint. Off-grid systems are also unable to take advantage of all the energy produced at peak resource times. If you are grid-tied, all the power that you harvest from your renewable source is fed back into the utility grid, wasting none of it. If you have the ability to be grid-tied, this would be your first choice for both financial and environmental reasons.
More to explain the value of being grid-tied, consider overall efficiency and economy of scale. BC has an amazing asset in its legacy of large dams that form the main source of electricity for our grid. They provide us with a storage system for energy that has a low environmental cost. These dams can act as a large battery bank that interacts almost seamlessly with solar and wind power. Integrated into the grid, the electricity that we get from solar and wind, which is intermittent, allows us to draw down our dammed water less, effectively ‘storing’ that energy, creating a more resilient grid. It is a personal choice to be off-grid, depending on one’s desire for independence, the costs of utility interconnection, utility dependability, lifestyle and personal preference. The choice to be off-grid is not ‘bad’ for the environment, but should be made with an understanding of the factors involved. ~