What is a Community Microgrid?
A community microgrid is an electricity distribution system that provides power to a neighborhood or small area of a city, town, or other community. It can be used as a backup for the main grid in case of failure or provide additional capacity during peak demand periods.
A microgrid is usually connected to the main electrical grid and has its own generation facilities (such as solar panels) and storage systems (batteries).
The term “microgrid” was first coined by Dr. William W. Moore III at MIT’s Lincoln Laboratory in 1999. In 2009, the IEEE published a standard on the topic, which defines a community microgrid as “a self-contained electric power supply network with local energy generation capability.”
This definition includes both renewable energy sources and non-renewable energy sources. For example, a community microgrid may include wind turbines, photovoltaic cells, fuel cell generators, diesel engines, natural gas engines, or any combination thereof.
A community microgrid also includes the necessary equipment to store excess energy generated from these resources. Some common residential energy storage options are batteries, flywheels, superconducting magnetic energy storage units, compressed air energy storage units, hydrogen tanks, etc. Energy stored in such devices can then be released when needed to meet peak demand periods.
The concept of a community microgrid is not new. Many communities have been experimenting with different forms of distributed generation since the 1970s.
However, the advent of smart meters and smart grids has made it possible to monitor and control the entire distribution system more efficiently. As a result, many utilities worldwide are now implementing or planning to implement community microgrids.
Why we need Community Microgrids
In recent years, there has been growing concern about the reliability of our current electricity infrastructure. The United States experienced a blackout in 2003 due to a storm surge caused by Hurricane Isabel. This event highlighted the vulnerability of our existing power grid.
More recently, the US Northeast suffered another major blackout in August 2016 due to a fire at a substation caused by lightning strikes. This incident led to widespread criticism of the US power industry.
As a result of these incidents, many countries are looking into ways to improve their electricity infrastructure. One solution being considered is the use of community microgrids. These are essentially smaller versions of the traditional utility grid. They are designed to operate independently of the larger grid if necessary.
Community microgrids would allow us to reduce the number of times the whole grid goes down. This will help prevent future blackouts like those mentioned above.
Another advantage of using community microgrids is that they could potentially increase the amount of renewable energy used in the country. If all homes and businesses were equipped with renewable energy sources, the overall impact of renewables on the grid would be much greater than it currently is.
Advantages of community microgrids
- There are several advantages to having community microgrids. They…
- Provide an opportunity for people to generate their electricity,
- Allow people to manage their energy consumption,
- Enable people to sell surplus energy back to the grid,
- Provide opportunities for people to buy energy from other users,
- Create jobs,
- Promote local economic development,
- Reduce pollution,
- Lower costs,
- Improve security,
- Reduce greenhouse gas emissions,
- Protect against cyber attacks,
- Improve resilience,
- Encourage innovation,
- Enhance social equity,
- Contribute to sustainable development,
- Improve the quality of life,
- Can save lives,
- Twenty-first, they can reduce poverty.
Disadvantages of community microgrids
Despite all of the benefits listed above, there are also disadvantages associated with community microgrids. Some of them include:
- The cost of installing a community microgrid may be higher than most consumers expect.
- It may take longer to build a community microgrid because of regulatory requirements.
- The cost of connecting to the main grid may be higher than expected.
- Communities may not have enough support to create a community microgrid.
Some communities may be reluctant to install a community microgrid because they do not want to lose control over their electricity supply.
How does a community microgrid work?
A community microgrid consists of two parts:
- An electrical generation system that produces electricity,
- And an electric distribution network that delivers the electricity to homes and businesses.
A community microgrid needs to connect to the main grid to produce electricity. It then uses its generator(s) to provide electricity when the main grid fails or is overloaded. The generator(s) can either run continuously or only when needed. When the main grid is working normally, the community microgrid connects to the main grid so it can receive power from the main grid.
When the main grid is overloaded, the community microgrid disconnects from the main grid and runs off its generator(s). The community microgrid has access to the same resources as the main grid but at lower rates. In this case, the community microgrid is called an islanded microgrid.
When the main grid works properly, the community microgrid receives power from the main grid at a rate equal to 100% of its total demand. However, if the main grid is overloaded or experiencing problems, the community microgrid will use less than 100% of its demand.
This means the community microgrid must store excess energy in batteries. If the battery capacity is large enough, the community microgrid can keep using the stored energy even after the main grid returns to normal operation.
If the community microgrid’s generator(s) fail, it loses access to the main grid and becomes an islanded microgrid again.
If a natural disaster or similar events damage the main grid, the community microgrid loses access to the main grids and becomes an island again.
Community microgrids and Islanding, or “Island mode”
Islands are places where people live who are completely isolated from other areas. An example of an island would be a small town surrounded by farmland. Another example would be a group of islands separated by water.
Community microgrids are similar to islands in terms of how they operate. They are both self-contained systems that rely on one another for power during times of emergency. Both systems are connected to the main grid through a single point of connection (SPOC).
A SPOC is a place where electricity is transferred between different networks. For example, a SPOC could be a substation, a transformer station, or a transmission line.
The difference between a community microgrid and an island is the size of the area that the community microgrid covers. Islands cover a very small area, while community microgrids cover a larger area.
In a microgrid community, residents no longer depend on the main grid for power. Instead, they generate their power using solar panels or wind turbines.
The community microgrid is still connected to the main grid because the SPOC keeps the two systems together.
When the community microgrid generates more power than it consumes, the community microgrid sends the extra power back to the main network through the SPOC. The main grid then distributes the power to all of its customers.
When the community microgrid is not producing any extra power, the community microgrid does not send any power back to the main system.
This process continues until the community microgrid produces enough power to meet its needs without sending any power back to the rest of the main grid. At this time, the community microgrid has become fully independent.
How do I know if my community microgrid is ready for islanding?
You don’t need to worry about your community microgrid being ready for islanding. When installing a community microgrid, your utility company will tell you what equipment you need.
Your community microgrid will be considered ready for islanding only after installing all the required equipment.
What is an example of a community microgrid?
An example of a community microgrids would be a neighborhood with a few solar panels and a wind turbine. This community microgrid could provide power for the entire neighborhood with sufficient sun or wind.
However, the community microgrid will lose access to the main grid if the sun doesn’t shine or the wind stops blowing. It will then become an island again.
Some real-life examples of a community microgrid
Many communities have implemented community microgrids. Some of these include:
- A village in India uses a combination of rooftop solar panels and wind turbines.
- A neighborhood in California that uses a combination of solar panels and wind turbines to produce energy.
- A town in Australia uses a combination of photovoltaic cells and wind turbines.
- A neighborhood in New York City that uses a combination of wind turbines and fuel cell generators.
- A neighborhood near Seattle that uses a combination of renewable sources such as solar panels and wind turbines
- A neighborhood in Texas that uses a combination of rooftop solar panels and wind turbines
- A village in Germany that uses a combination of biomass plants and wind turbines
- A community in Canada that uses a combination of hydroelectric dams and wind turbines
- A town in Japan that uses a combination of hydropower stations and wind turbines
- A school district in Florida that uses a combination of small scale solar panels and wind turbines