The Macro Grid Initiative seeks to expand and upgrade the nation’s transmission network to deliver job growth and economic development, a cleaner environment, and lower costs for consumers. The 15 states between the Rockies and the Mississippi River account for 88 percent of the nation’s wind technical potential and 56 percent of solar technical potential. However, this region is home to only 30 percent of expected 2050 electricity demand.

Through a transmission Macro Grid, we can connect centers of high renewable resources with centers of high electric demand, enhance grid resiliency and dramatically reduce carbon emissions.

Expanding and upgrading the nation’s transmission network will deliver jobs and economic development, a cleaner environment, and lower costs for consumers.

MGI Vision Statement Supporters

Building the Macro Grid

  • Saves Consumers Up To $47 Billion

    $47 Billion

    Increased transmission development at the “seams” between regions could save consumers up to $47 billion annually

    America’s centers of high renewable resources and high electric demand, represented here through resource type and population size respectively, sometimes fall within different grid regions.

    Map: America’s Centers of High Renewable Resources and High Electric Demand
    Source: National Renewable Energy Laboratory, Interconnections Seam Study

    Stitching together the major regions of the power system, represented here conceptually, would allow the U.S. to harness its abundant renewable resources and balance electric demand across the country.

    Map: Major Regions of the U.S. Power System
    Source: National Renewable Energy Laboratory, Interconnections Seam Study, Scenario 2b


    Upgrading America’s transmission system by building a Macro Grid is a cost-effective way to alleviate transmission congestion and allow the integration of new renewable energy, which is expanding rapidly due to competitive prices, corporate procurement goals and state renewable energy standards. The Macro Grid Initiative seeks to build public and policymaker support for a new policy and regulatory environment that recognizes the substantial nationwide benefits of new regional and interregional transmission. Priority areas include:

    An expanded nationwide and eastern grid with a focus on the regions of MISO, PJM and SPP

    The next round of regional and interregional transmission planning

    A fully planned and integrated nationwide transmission system

    A new Federal Energy Regulatory Commission transmission planning rule


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    Relevant Studies Highlighting the Benefits of a Macro Grid

    Report on Barriers and Opportunities for High Voltage Transmission - FERC

    In its Report on Barriers and Opportunities for High Voltage Transmission, the Federal Energy Regulatory Commission (FERC) provided a strong endorsement of large-scale transmission, stating that, “high voltage transmission can improve the reliability and resilience of the transmission system by allowing utilities to share generating resources, enhance the stability of the existing transmission system, aid with restoration and recovery after an event, and improve frequency response and ancillary services throughout the existing system.” FERC also touted the climate benefits of transmission, highlighting that “transmission can help states achieve their renewable portfolio standards (RPSs) and renewable portfolio goals” and that “high voltage transmission can help states achieve their greenhouse-gas emission reduction targets” by increasing the availability of carbon-free energy and facilitating the replacement of fossil fuels. FERC also found that “transmission investments improve competition in wholesale markets by reducing congestion and allowing the lowest-cost resources to compete.” In the report, FERC also examined opportunities for future transmission expansion, including the co-location of transmission along existing rights of way, such as railroads or highways, noting that “co-location of transmission in transportation corridors could reduce both the negative effects caused by a project and the cost of project development.”

    Grid Vision: The Electric Highway to a 21st Century Economy - AWEA

    Grid Vision provides three key policy recommendations for realizing the benefits of an expanded transmission system. These three recommendations are centered around the “Three Ps” of Planning, Paying and Permitting, which call for forward-thinking and collaborative transmission planning, broad transmission cost allocation to reflect the broadly distributed benefits of transmission, and the simplification of interstate transmission line siting, respectively. Grid Vision concludes that expanding the current transmission system network could save consumers as much as $47 billion annually, a roughly 10 percent reduction in electric bills.

    Interconnections Seam Study – National Renewable Energy Laboratory

    The National Renewable Energy Laboratory (NREL) conducted the Interconnections Seam Study to analyze the costs and benefits of optimized nationwide transmission expansion. NREL analyzed several study scenarios aimed at connecting the nation’s main grid regions. The scenarios included:

    • Design 1: The “control” scenario in which existing HVDC ties between the Western and Eastern Interconnections are replaced at their current capacity and new AC transmission lines are built on either side co-optimized to minimize costs.
    • Design 2a: The capacity of existing HVDC ties are increased slightly along with the construction of AC lines on either side of the interconnection.
    • Design 2b: New HVDC lines are built across the seam with supporting AC lines on either side.
    • Design 3: The addition of a nationwide high-voltage HVDC network.

    Each design scenario was run under two separate policy cases – the current policy case (assumes existing renewable portfolio standards as of 2017) and the carbon pricing case (carbon pricing that grows at a rate of $3/metric ton of CO2 per year to reach $40/metric ton by 2038). The report shows the benefit-to-cost ratio under the current policy case for designs 2a, 2b, and 3 are estimated to be 1.26, 1.13, and 1.15, respectively, per $1 invested over a 15-year period. Under the carbon pricing case, the benefit-to-cost ratio for designs 2a, 2b, and 3 are estimated to be 2.48, 3.3, and 2.52, respectively, per $1 invested over a 15-year period. Additionally, the study found annual production cost savings to range from $0.8 billion to $2.5 billion over a 15-year period under the current policy case and from $1.9 billion to $3.8 billion over a 15-year period under the carbon pricing case.

    Informing the Transmission Discussion - WIRES

    Informing the Transmission Discussion offers an overview of the challenges each US region faces as a result of changing energy mixes, increases in electrification, increases in demand-side variability from DERs and energy storage and the need for location-constrained renewables. The study looks at the current regional transmission landscape and examines what must be done to address these challenges, finding that transmission is a critical solution for meeting both clean energy and resilience objectives. Informing the Transmission Discussion also details how the electrification of buildings and vehicles will increase demand for electricity supply and renewable resources, with an estimated $7 to $25 billion in transmission investment needed by 2031 to meet these needs.

    Future Cost-Competitive Electricity Systems and Their Impact on US CO2 Emissions - MacDonald, Clack et al.

    Future Cost-Competitive Electricity Systems and Their Impact on US CO2 Emissions, funded by the National Oceanic and Atmospheric Administration and published in the Nature Climate Change journal, models the benefits of constructing a nationwide HVDC transmission network designed to tap into renewable and other low-carbon resources geographically dispersed throughout the country. Under such a network design, approximately 60 percent of U.S. power sector electricity could be generated from wind and solar resources alone. The study analyzes the emission reduction potential of the transmission network shown above under three scenarios:

    • A high-cost renewable and low-cost natural gas (HRLG) scenario;
    • A low-cost renewable and high-cost gas (LRHG) scenario in which the US achieves future; expected cost reductions for renewable energy and sees increased demand for natural gas; and
    • A mid-cost renewable and mid-cost natural gas (MRMG) scenario, which averages the HRLG and LRHG scenarios.

    With new HVDC lines to access resources more efficiently, the HRLG, MRMG and LRHG scenarios are expected to reduce power sector emissions by 33 percent, 61 percent, and 78 percent, respectively, compared to 1990 levels. Additionally, consumers are expected to save as much as $4.7 billion annually under the LRHG scenario, which is roughly the equivalent of a 10 percent reduction in electric bills or roughly three times the cost of the HVDC transmission builds per year.

    North American Supergrid: Transforming Electricity Transmission - Climate Institute

    North American Supergrid: Transforming Electricity Transmission is an initiative of the nonprofit Climate Institute that contemplates a North American Supergrid, or a largely underground, nationwide HVDC network that would extend across the lower 48 states, improving national security and enabling higher penetrations of cost-effective renewable energy. The landmark study also examines the technical and engineering challenges with implementing a largely underground HVDC system, estimating such a network would create hundreds of thousands of jobs over several decades. Approximately two-thirds of the HVDC cable links in the proposed system can feasibly be placed underground along existing rights of way, greatly reducing the time and effort needed to move forward with permitting and construction, according to the report.

    Minnesota’s Smarter Grid - Vibrant Clean Energy

    Minnesota’s Smarter Grid, a study performed by Vibrant Clean Energy, models eight future Eastern Interconnection electric system scenarios to determine the optimal pathways through which Minnesota can meet its state goal of decarbonizing its economy 80 percent from 2005 levels by 2050 (80×50). A more flexible grid with increased interstate transmission can efficiently support the large amount of renewable resources needed to meet decarbonization goals while providing service at costs lower than current costs and costs incurred through a lack of interstate transmission. The study finds that scenarios with interstate transmission expansion can introduce annual savings to Minnesota consumers of up to $2.8 billion, with an annual savings for Minnesotan households of up to $1,165 per year.

    New Jersey Integrated Energy Plan - New Jersey Board of Public Utilities

    New Jersey’s Integrated Energy Plan, commissioned by the state’s Board of Public Utilities and based on analysis by the Rocky Mountain Institute, finds that existing New Jersey policies will not be sufficient to meet the state’s clean energy goals. Modeling of the least-cost pathways to meet these goals finds that PJM-to-New Jersey transmission will need to be increased from 7 to 9 gigawatts in order to achieve the state’s 100 percent carbon-neutral by 2050 target. This enhanced transmission capacity will allow New Jersey to cost-effectively import electricity from new out-of-state wind and solar plants.