Microgrids and energy storage system: definition, application, advantages
Microgrids and energy storage systems are a much talked about topic lately.
In fact, they have been playing an important role in dealing with, and recovering from, tropical storms and hurricanes effects that recently hit North America.
Microgrids provided energy to stores and fuel stations, offering essential products and services – such as water, food and fuel – that helped a huge amount the residents to survive and deal with this emergency.
But what exactly are microgrids and what are their uses in conjunction with storage systems?
Content of the article
- What is a Microgrid
- Microgrids: principal applications
- Microgrids in remote areas
- Microgrids for businesses, Universities and military bases
- Microgrids and energy storage system advantages
- The example of Santa Rita Jail in California
- Microgrids and energy storage system: climate change, remote areas needs and financial advantages
What is a Microgrid
This is how the U.S. Department of Energy Microgrid Exchange Group defines them:
“A microgrid is a group of interconnected loads and distributed energy resources (DERs) within clearly defined electrical boundaries that acts as a single controllable entity with respect to the grid. A microgrid can connect and disconnect from the grid to enable it to operate in both grid-connected or island-mode”.
Put it more simply, a microgrid is just a localized power grid that can operate independently or together with the area’s main electrical grid.
Microgrids: principal applications
However, it’s important to remember that microgrids are not just used in emergency situations.
Let’s see what are the principal applications of microgrids.
Microgrids in remote areas
Microgrids are an effective solution in remote areas, like islands for example, which are without access to a national electricity transmission network.
The island of El Hierro in the Canary Islands, for instance, has a 34MW microgrid, where energy is created by wind turbines when wind resources are available and otherwise by diesel.
Any unused power is channeled to pump water uphill and then into an old volcanic crater where it is stored in a big lake to be eventually be released downhill to power hydro turbines.
Microgrids for businesses, Universities and military bases
Microgrids can also be used in many other situations by businesses, universities and military bases to provide constant power in case of grid defects.
Sometimes, using the appropriate storage systems, they are used to reduce the cost of power by replacing electricity from the grid at peak times of the day.
For example, the University of Ontario in Canada has built a 5MW microgrid, where solar PV, diesel and lithium-ion batteries work together and even the US Army has a 2.6MW microgrid in its military base in Hawaii powered by diesel, wind and flow.
Microgrids and energy storage system advantages
Within microgrids, energy storage systems provide much more than just a supportive source of power.
At utility level they serve other important functions, such as smoothing intermittent PV power flow, regulate frequency and voltage control.
At consumer level they can boost the supply at peak periods (peak shaving) and offer important backup in case of emergencies as described above.
To put this into context, let’s imagine that the sun moves behind a cloud (or at night) or the wind stops blowing.
A microgrid can then engage its stored energy while waiting for the other source of energy to come back online, keeping the lights on.
The example of Santa Rita Jail in California
The Santa Rita Jail in California is a good example of how advantageous microgrid and energy storage systems can be.
This state prison reduced its peak demand by 95 percent, and increased its energy supply after it installed a microgrid.
Microgrids and energy storage system: climate change, remote areas needs and financial advantages
Microgrids and storage system are nowadays extremely important tools to build climate change resilience and to offer energy solutions to remote areas.
They are also attractive at a financial level as in conjunction with the appropriate storage systems can provide individual and business energy at cheaper rates.
A number of really good reasons that will hopefully encourage more people, business and governments to look into these systems and to hopefully join the energy revolution.