It is impossible to imagine a world without electricity. We have become so dependent on uninterrupted power supply that when it fails, our life turns upside down. Power outages in the United States have seen an alarming rise since 2008.[s1] According to the North American Electric Reliability Corporation (NERC) and Federal databases established at the Department of Energy (DOE), America has witnessed more and longer power outages than any other developed nation in the world in the past decade. At a time, when the country is faced with the challenge of reaching its carbon emissions reduction goals while maintaining the safety and reliability of the power supply, ramping up microgrid systems can become a key component of this effort.
Microgrids are autonomously managed and powered localized grids which are composed of one or more generation units connected to nearby users. They can be operated with, or independently from, the ‘macrogrids’, enabling them to ensure uninterrupted power supply. As they have the ability to operate while the main grid is down, they can strengthen grid resilience and mitigate grid disturbances.
In the past, microgrids generated power using fossil fuel powered combined heat and power (CHP). However, today’s microgrid projects support a flexible and efficient electric grid by enabling the integration of other distributed generation sources, including renewable energy sources.
Microgrids are mainly of three types:
- Remote microgrids: Provide power to communities far from utility networks
- Customer-owned microgrids: Microgrids used at large facilities fall in this category, such as military bases and college campuses
- Utility distribution microgrids: These are the portions of the grid within the utility system that can act as microgrids
Factors Driving the Movement towards Microgrids
In the recent years, when climate change has become the most important issue haunting nations, interest in microgrids has grown astronomically due to the following reasons:
- They can deploy clean energy sources: Microgrids have the ability to deploy renewable energy sources, natural gas-fueled combustion turbines, and even emerging sources such as fuel cells or small modular nuclear reactors.
- Uninterrupted power supply: They can provide uninterrupted power supply to critical facilities, like hospitals, universities etc. during a weather- or security-related outage since they have the ability to function independently from the surrounding system.
- Reduced line-losses: In traditional power grids, when power is supplied over long distances, line losses occur, requiring additional power generation to meet the demand. Since Microgrids make use of on-site energy (also known as distributed generation), line loss is minimal and less power is required to meet the same level of demand.
- By-products can be used productively: Since in microgrids, power is generated close to the end users, the heat generated can be used productively; for example, heating water or spaces in nearby homes and businesses.
- Lower electricity prices: When placed strategically within the electricity system, microgrids help manage electricity demand and reduce grid congestion, thus lowering electricity prices and reducing peak power requirements.
- Enhanced grid resilience: Microgrids can enhance grid resilience to extreme weather or cyber attacks.
Challenges in the Way of Microgrid Deployment
While microgrid model has many advantages to offer, there are some challenges in the way of implementing microgrids.
- Issues related to microgrid interconnection
- Cost challenges
- Regulatory challenges
- Unique tech requirements for the complex control systems.
Solutions for Encouraging Microgrid Deployment
Even though there are challenges, there are ways to combat them. Here are some solutions that can possibly address the challenges faced by the microgrid industry:
- Public-private partnerships: Mixed ownership can help overcome financial hurdles. For example, Microgrid partnerships at Peña Station Next in Denver, Colorado.
- Encouragement by states: Connecticut, California, Massachusetts, New York, and New Jersey have created funding opportunities for microgrids. For example, New York has established a $40 million grant program to facilitate community microgrid projects.
- A clearer legal framework is required: A clearer legal framework would help define a microgrid and set forth the rights and obligations of the microgrid owners.
Microgrid Deployment in the US – Current Picture
- Microgrids constitute less than 0.2 percent of electricity in the U.S., but in the next three years, their capacity is expected to increase substantially.
- Out of 160 microgrids in the U.S., most are concentrated in seven states: California, Alaska, Georgia, New York, Maryland, Oklahoma, and Texas.
- NRG Energy, one of the largest U.S. independent power producers, has implemented a microgrid in its Princeton, New Jersey, headquarters to bolster resilience, help lower electricity bills, and act as a place to test ideas for real-world applications.
The benefits of microgrids are numerous and with an increased interest in the area, the ‘power system in a box’ solution has come to technical maturity. It’s about time we start thinking of maximizing the implementation of microgrids to improve reliability and resiliency of traditional grids and keep the nation moving towards a clean energy future.