Smart Grids and Microgrids
Compendium on Smart Grids and Microgrids
June 6 2023
by Timothy Nolan
The Need for National-Level Transmission Planning in America
Building a Nationally Connected High Voltage Transmission Network would save the U.S. more than $40 billion annually, according to multiple studies analyzing how to decarbonize the grid by 2050 American Council on Renewable Energy Macro Grid Initiative - ACORE
Extrapolated from Source: Transmission-Planning-White-Paper.pdf (esig.energy)
The widespread adoption of clean energy goals by many U.S. states and businesses is underway, spurred by accelerating commitments to combat climate change and the growing cost-competitiveness of renewable resources. To meet ambitious decarbonization goals that aim to reach 100 percent clean electricity by 2035 and net-zero emissions across the economy by 2050. Reaching these goals efficiently will require a doubling or tripling of the size and scale of the nation’s transmission system.
Decarbonizing the electricity system, and ultimately achieving net-zero emissions, will require action on a transformative scale. Dramatic amounts of additional utility-scale and distributed zero-carbon generation will be needed to decarbonize the power system and maintain grid reliability to meet the 2035 and 2050 goals.
Proactive national transmission planning is critical to meet the current goals quickly and affordably. In a 100 percent clean electricity future, large amounts of wind, solar, and storage will be needed in varying densities in many locations, and transmission will be critical to ensuring that energy can be delivered from where it is produced to where it is needed.
As the continent pushes to decarbonize, significant geographic pockets of wind and solar resources will be built primarily in remote areas with the strongest wind and solar resource potential. However, to decarbonize the electricity system a well-designed macro grid is needed to deliver affordable, clean electricity where it is needed any hour of the day or night.
Although zero-carbon wind and solar energy dominate the new electricity generation built over the past decade, and proposed generation in the coming years, it is important to accelerate development of all types of clean electricity generation. But there is not enough electricity transmission available to connect all the proposed new generation to the grid and deliver energy to customer centers.
Transmission has been constructed to meet incremental needs, but the pace of transmission needed to facilitate the clean energy transition is lagging. There are two main reasons: a lack of agreement about where the future generation will be located, and a lack of agreement about who benefits from the transmission and therefore who should pay for the transmission expansion.
Due to the lack of transmission capacity expansion, many proposed generation and storage resources have been unable to interconnect to the grid. Because the highest-quality wind and solar resources are often located where the existing grid is the least developed, transmission interconnection queues have amassed over 600 Giga watts of proposed generation capacity as many projects are unable to go forward due to a lack of grid access.
Without a system-wide approach to transmission planning and a significant expansion of interregional transmission, studies show that effective economy-wide decarbonization will be much more expensive. A continuation of local and regional-focused transmission planning will slow the integration of low-cost renewable and other clean generation sources into the grid.
A decade’s worth of energy system studies focused on the decarbonization of the U.S. electricity system and economy have found that significant transmission expansion is essential to realize effective low carbon energy systems at the lowest cost. Recommendations for decarbonizing the electricity system, and ultimately the U.S. economy, are based on three complementary recommendations:
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National transmission planning: establish a national transmission planning authority and initiate an ongoing national transmission planning process.
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Renewable energy zones: designate renewable energy zones for large-scale wind and solar resource development and build large-scale transmission to those regions to expedite coordinated generation and transmission expansion.
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Macro grid concept: the develop and implement a national transmission network (the macro grid) of multi-regional, high-voltage transmission that unites the country’s power systems.
This macro grid will enable nation-wide access to all clean energy sources. It will use proven transmission technologies for a scalable, no-regrets solution to develop the great magnitude of clean generation resources that will be needed to meet national decarbonization goals.
Project Drawdown Microgrids | Project Drawdown defines our Microgrids solution as the use of localized groupings of electricity sources and loads that normally connect to the traditional centralized power grid, but can disconnect and function autonomously. It replaces the conventional practice of powering buildings and communities with electricity from a centralized grid.
A microgrid is semi-autonomous and can locally control loads and supply. A typical microgrid might include distributed generation technologies such as wind, solar, hydropower, or biomass, together with energy storage units or backup generation and load management tools. Microgrids can play a critical role in boosting grid flexibility and efficiency.
For higher-income countries, the benefits of microgrid systems fall under our Grid Flexibility solution and also under the impacts of increased adoption of decentralized variable renewable energy sources.
An optimal combination of centralized and decentralized systems can capture both the strength of the central grid and the agility of decentralized infrastructure. Microgrids can help bridge the gap between electricity supply and demand while making use of locally available energy resources.
Microgrid infrastructure enables a transition to a decentralized power system that is more reliable, affordable, and sustainable.
Microgrid installations in grid-connected regions also offer several key advantages, including optimized energy consumption through better matching of supply with demand; reduced environmental impact through integration of renewable energy sources; increased security of energy supply; provision of cost-efficient electricity infrastructure; and the ability to allocate power supply to high-priority needs during times of disruption. Microgrids | Project Drawdown
Macrogrids Versus Microgrids
Microgrids vs. the Macrogrid: The Applications of Microgrids in Today’s Power Systems - News (allaboutcircuits.com) "A microgrid is a group of interconnected loads and distributed energy resources 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."
A microgrid is a system of energy sources, energy consumers, and energy storage. This system can operate independently from the traditional centralized power grid (macro grid) in “island” mode. Alternatively, in the grid-connected mode, it can be a source of power to the macrogrid or it can draw power from the macrogrid as conditions demand.
Macro Grid Initiative - ACORE The Macro Grid Initiative is a joint effort of the American Council on Renewable Energy and Americans for a Clean Energy Grid to promote investment in a 21st century transmission infrastructure that enhances reliability, improves efficiency, and delivers more low-cost clean energy.
ACORE-Enabling-Low-Cost-Clean-Energy-and-Reliable-Service-Through-Better-Transmission-Analysis.pdf
Home (cleanenergygrid.org) Americans for a Clean Energy Grid (ACEG) a non-profit broad-based public interest advocacy coalition bringing together diverse support for an expanded and modernized grid from business, labor, consumer, environmental groups, and other stakeholders to advance policy that recognizes the benefits of a robust transmission grid.
Increasing energy generation from cleaner sources demands an increase in transmission and distribution networks. Doing so, along with greater interconnectivity amongst grids, can counter renewables' intermittency and create more stable networks.
What’s the difference between a smart grid and a microgrid?
Electric Power Engineers Jul 25, 2022 What’s the difference between a smart grid and a microgrid? - Electric Power Engineers (EPE) (epeconsulting.com)
Smart grid and microgrid technology each is a different concept and have their own respective applications. It’s crucial to understand both grid types as they are essential components of grid resiliency and reliability. The main difference between the smart grid and microgrid is scale. As the name suggests, the microgrid is engineered to work in small community areas. The smart grid is designed to handle power supply for large communities and is the digital technology used for two-way communication between utilities and their customers, and sensors along transmission lines.
Microgrids have many benefits. They can operate as a local source of generation or a component of a decentralized electricity group. The ability to switch between the island and connected modes allows for security for the energy supply. Microgrids increase reliability for rural communities that are geographically distanced from centralized generation and dependent upon radial supplies.
There are five types of microgrids: campus environment microgrids, community microgrids, remote off-grid microgrids, military base microgrids, and commercial microgrids. Each type of microgrid is intended for a specific location.
Understanding Smart Grids Smart grids provide electricity through two-way digital technology. The smart grid analyzes, controls, and monitors communications from the utility, via transmission lines and at the consumer level. Smart grids operate based on digital technology. The smart grid was developed to address the shortcomings of the conventional grid. The smart grid has the potential to reduce costs and maximize the transparency of the supply chain. Smart grid technology is useful in today’s energy sector due to its ability to deal with climate change and energy independence scenarios. Consumers with electric vehicles benefit from smart grid technology that allows them to have lower rates when charging their vehicles. The smart grid aims to maximize the energy system output while reducing the resources needed to produce said energy.
Minnesota’s Smarter Grid Pathways Toward a Clean, Reliable and Affordable Transportation and Energy System Study 2018
Projects Minnesota’s Smarter Grid - GridLab
Minnesota’s Smarter Grid - ACORE
For the Minnesota economy to achieve an 80% reduction of greenhouse gas emissions by 2050, in line with its legislative goals, the electricity sector must decarbonize by at least 91%. Energy models indicate that a heavily decarbonized electric sector is possible at prices comparable to or lower than current electric costs, with a heavy focus on energy efficiency, along with the electrification of space heating, water heating, and transportation systems. A massive deployment of renewable energy will not disrupt the reliability of the electric grid, although increased transmission upgrades, as well as heavy transmission sharing and grid integration with neighboring states will be important to keep costs down as the sector decarbonizes. As natural gas and nuclear energy play a diminishing role in the states capacity mix, the flexible grid can efficiently support high penetrations of renewable energy as well as electrified heating and transportation systems. This flexible grid has the bonus of improving air quality across all major human pollutants and reducing greenhouse gas emissions. The decarbonized trajectories will deliver both jobs and increased revenue to the state of Minnesota, with no sacrifice to system reliability or services.
The study modeled electric sector scenarios to determine optimal pathways that significantly decarbonize Minnesota’s economy, in alignment with the Act’s goals. The study was funded by the McKnight Foundation, managed by GridLab, and executed by Vibrant Clean Energy.
Minnesota Microgrids: Barriers, Opportunities, and Pathways Toward Energy Assurance Prepared by Microgrid Institute for the Minnesota Department of Commerce Final Report September 30, 2013. This project was made possible by a grant from the U.S. Department of Energy and the Minnesota Department of Commerce through the American Recovery and Reinvestment Act of 2009 (ARRA).
Minnesota Microgrids: Barriers, Opportunities, and Pathways Toward Energy Assurance (mn.gov)
Microgrid Institute - Resources - Microgrid Institute
Microgrid Drivers and Enabling Factors
Numerous factors are driving increased interest in microgrid solutions – not only in Minnesota and the United States, but around the world. The key factors are:
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Energy Assurance: The need for stable and sustainable energy supply at sites deemed critical for public services and safety, especially during wide-scale outages and natural disasters.
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Reliability: The need for greater resilience and reliability at high-priority commercial, industrial, military, and other sites, where outages can cause serious disruption, risks, and financial costs.
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Clean Energy Development: Public policy goals for increasing utilization of renewable resources, improving system efficiencies, and reducing greenhouse gas (GHG) emissions and other environmental effects of energy services.
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Economic Development: Imperatives for encouraging and facilitating economic development, attracting new businesses, creating jobs, and advancing technology capabilities.
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Disruptive Technologies and Forces: Transformative industry trends that make distributed generation (DG), energy storage, and energy management technologies more useful and cost-effective for a wider range of applications, which increasingly could challenge the traditional utility business model.
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Local Self-Reliance: Energy end-users’ interest in alternative service models, especially those that enhance local self-reliance, environmental quality, and economic health.
Microgrids that can operate in isolation from a utility grid can help communities’ efforts to recover from natural disasters and restore normal operations – both in public infrastructure and economic activity. Specifically, microgrids could provide energy assurance for critical sites, such as police and administrative facilities, hospitals, and public shelters, when disasters trigger cascading effects in interdependent systems and sectors.
Microgrids face serious impediments in Minnesota. Many of these involve policy barriers and
uncertainties. But just as importantly, the microgrid platform remains a technical and economic work in progress. Although microgrids have been operating for decades, the integrated, flexible, fully featured microgrid concepts that have sparked the keenest interest today are almost nonexistent outside of laboratories and limited demonstration projects. Note: These circumstances may have changed in almost 10 years since this report, such as the microgrid research at University of St. Thomas
In addition to the few advanced microgrids operating in the United States today, dozens more are in development in this country, with hundreds more around the world. Tens of thousands of U.S. sites are available for potential microgrid development as technologies and business models mature. Importantly, the microgrid concept itself is highly flexible and adaptable, accommodating an extremely wide range of possible applications and solutions. Almost all options for major component technologies and models considered for use in microgrids are advancing and improving – some of them at a very fast pace, and others more slowly. The microgrid topology can be applied in countless different scenarios, scaling from the very small to the very large.
Beyond the concept of a microgrid for a single facility or campus, a few utilities are considering designs that would create loops within an existing distribution system, adding distributed generation (DG) and energy management systems to create a microgrid within the architecture of the macro grid. Proposals for community microgrids envision the creation of energy improvement districts and cooperative associations, combining the diverse resources and requirements of clustered facilities and customers. All these approaches represent forward pathways for microgrids, and development along any path will bring technological advances and best practices that support the others.
Barriers and Opportunities for Microgrid Development
Most of the impediments to microgrid development in Minnesota involve four major factors:
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Utility practices, requirements, and planning norms
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Regulatory and policy barriers, gaps, and disincentives
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Perceived risks, costs, and complexities for execution
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Limited technical assistance and support
Specifically, utility practices in many cases actively or inadvertently deter microgrid development. Utility power systems engineers understandably view any customer-owned DG as technically questionable until proven otherwise. Most utility system planners do not consider microgrids as potential resources or assets capable of addressing system constraints – or deferring capital expense requirements. Many utility executives consider microgrids, as part of the broader class of distributed energy resources (DER), to be potentially competing and disruptive technologies. Minnesota law is virtually silent on microgrids, which leaves major uncertainties across many areas of regulation, policy, and incentive benefits and provisions that are available to other types of energy assets and resources. Finally, microgrid developers face normal resistance to change among potential end-use customers and host facility owners. Key question is what further changes are necessary in policy and law.
All of that resistance notwithstanding, substantial opportunities exist in Minnesota for developing microgrids that provide tangible and important benefits to the state. In addition to microgrids’ direct benefits for energy delivery, efforts to develop them will foster economic growth, technology development, and educational advancements in Minnesota.
Policy Pathways for Minnesota Microgrids
Minnesota has a solid tradition of supporting DG, renewable energy, and efficient alternatives. Generally, policy steps involve:
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Setting and clarifying the role of microgrids in the State’s policy vision and priorities and integrating that role in regional planning.
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Removing or reducing regulatory barriers and artificial, outdated institutional impediments to microgrids.
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Establishing statutory frameworks and processes to support microgrid development as part of the State’s utility planning and oversight roles.
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Initiating and supporting a microgrid pilot program
The Minnesota Microgrid Pilot Program would provide a vital platform for developing and financing microgrids in the state. But its success hinges in part on efforts to advance the policy landscape so that it accommodates and supports microgrids, allows their development, and serves to attract available capital. The State should define “microgrid” for policy purposes and reinforce the State’s interest in enabling and encouraging microgrid development – consistent with its energy, environmental, and economic policy roles. Microgrids also should be integrated as part of a strategic review of utility industry transformative forces to ensure planning processes appropriately consider new technologies and business models.
Micro Grid Information Links
How do microgrids work? - YouTube
Microgrids: Our Energy Future - YouTube
The Anatomy of a Microgrid - The Pros and Cons of AC and DC Coupling - YouTube
Micro Grid Project Examples
State of Minnesota Publishes Microgrid Policy and Market Study - Microgrid Institute
Microgrids – what they are, and why they can save us all. - Institute on the Environment (umn.edu)
Microgrid Project in Minnesota | OATI
Microgrid Technology Center | OATI
Cummins opens new Microgrid testing lab in Minnesota | EnergyTech
Power Integration Center | Cummins Inc.
Types of microgrids, with examples | Cummins Inc.
Microgrid Research | University of St. Thomas - Minnesota (stthomas.edu)
In 2023 the University of St. Thomas Center for Microgrid Research will receive $7.9M in funding to continue its innovation efforts and bring key investments to our state.
This Minneapolis microgrid could serve as a jobs training and resiliency hub | Energy News Network
Microgrid technology comes to Bloomington Minnesota. (21stcentech.com)
Best Practice Action Detail | GreenstepCities (state.mn.us)
In Minnesota, an Arctic explorer's off-the-grid dream becomes reality | Energy News Network
Cogeneration Distributed Generation | Wright-Hennepin (whe.org)
Renewable energy options | Wright-Hennepin Electric (whe.org)
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