Microgrids – what they are, and why they can save us all.
By Jack Vehmeier
The word microgrid is somewhat of a buzzword that gets thrown around when talking about power systems and renewable energy, but when talking to the general public many people do not know what they are or more importantly how much good they can do. In this blog we will explain what this buzzword is actually talking about and how important it is that microgrids start becoming more prevalent across the world.
Microgrids are essentially small, smart power systems that are self sufficient and are able to supply a specific area. These areas can include a business complex, a neighborhood, a school or university or even a hospital grouping. The main idea of a microgrids is to have generation local with in comparison to where the customer need the power. Typical large grids or the central grid have power plants or generation located very far away from their customers and rely on long transmission lines, substations, distribution lines all which add many inefficiencies to the existing grids. It is estimated that up to 15% of electricity can be lost as part of the transition process. Microgrids are composed of generators, batteries, loads, a connection to the central grid and a smart controller. It maintains a connection to the central for reliability as well as for situations where it is better to take power from the central grid. The smart controller serves as the smart, Internet of Things, system of the microgrid which can be designed to achieve a variety of different goals based on what is happening in the current environment. For example, it can be designed to provide the cheapest energy possible to its customers, or it can be designed to use as much clean energy as possible while still maintaining reliability. Not many microgrids currently exist, but the market is rapidly growing due to the closing of major coal plants and the influx in renewables being added to the grid. If it is still hard to imagine what one would look like refer to this image below which shows what a microgrid could look like in a neighborhood. Notice the direct connection with various types of generation as well as the towers which are connected to internet to enable the smart communications.
The next, bigger question is why are microgrids better than what we currently have and how can they help fight the climate change battle? One of the ways that microgrids are better than a centralized grid is the reliability that they offer. In an idealized society with thorough distribution of microgrids each individual microgrid would have self-contained generation that would be enough to sustain their power needs. This means that during extreme weather situations less power outages would be sustained due to less reliance on long transmission lines and more reliance on smaller contained systems. This is a very important topic especially in the United States. Over the past couple of year we have seen events such unexpected cold fronts in Texas, Hurricane Isaias, and extreme heat in California all of these events caused tens of millions of Americans without power for days and even caused deaths due to no access to electricity. All of these event caused blackouts due to the large reliance on the centralized grid, in almost all cases of sustained blackouts in the US could be avoided by having self-contained microgrids. Microgrids would also put less stress on the centralized grids so situations of extreme heat would not effect the grid as much. On top of this boosted reliability microgrids contain major environmental benefits. First of all it is simply easier to integrate renewable energy generation on a contained microgrid and the smart controller can be designed to prioritize the use of the clean energy first and only use fossil fuels in cases of need. Also in the cases of fossil fuel plants needing to be used they can be made more efficient because they will be located closer to the customer and there will be less losses in transition. Also there have been proposals to use the heat produced from fossil fuel plants to heat water or houses since they will be located close to customers. These reasons just simply start the conversation on what microgrids can do to save us, but there are numerous others and also many innovations on the way that can make microgrids even better. It’s a necessity for our future to invest in microgrids.