Green sense - Overseeing the power grid

When you use electricity matters. The electric grid is managed to avoid power outages, and uses standby power plants to ensure generation capacity is available.

A sprawling network of power plants, transmission lines, and distribution make up the U.S. electric grid. Power plant-generated electricity, transmitted at a very high voltage over big transmission lines, is converted to a lower voltage via transformers, and travels through substations to be distributed to homes and businesses.

It's a constant balance between the supply and demand for the electricity that powers everything from industry to our homes.

"The Grid" usually only comes to public attention when large-scale failures occur, such as the Texas blackouts in early 2021 and the failures in the Southeast this winter. These failures point to some of the hurdles to address climate change.

Cutting emissions through electrification, which includes the transition to electric vehicles, will require a clean, reliable energy grid.

According to a backgrounder from the Council on Foreign Relations (www.cfr.org), "Extreme weather events influenced by climate change and vulnerability to cyberattacks have raised concerns about the grid's reliability. Emissions from electricity generation are a substantial driver of climate change, and there is an urgent need to transition away from fossil fuel–based power."

According to the U.S. Energy Information Administration (EIA, www.eia.gov), fossil fuel–based power plants - burning coal, oil, or natural gas - create about 60 percent of the nation's power, while nuclear power accounts for nearly 20 percent. Smaller percentages include various renewable resources.

The complicated system that matches generation with transmission and distribution here is overseen by a nonprofit organization based in Holyoke called Independent System Operator-New England.

This organization operates the region's bulk power transmission system as well as the wholesale electricity markets that cover New England's six states.

In 2019, eight senators from New England wrote to ISO-NE that their current policies do not support the region's climate and environmental goals. ISO-NE's "Forward Capacity Payments" are currently used to preserve "the status quo of a fossil fuel-centered resource mix." This system is intended to provide security and redundancy, making sure there is always extra energy on the grid and helping avoid disastrous outages, but "will force consumers to pay millions of dollars to existing, polluting power plants with on-site [fossil] fuel supplies."

Capacity means there are power plants on standby, ready to kick on and deliver electricity when needed, for example, on the hottest summer day when everyone has turned on air conditioning and is also making dinner after work.

When everyone is using more electricity than they usually do, power plants have to produce more to avoid outages.

If you think of the demand for electricity as a curve, low at night and rising in the morning and during the day when all the things that need electricity are turned on, the greatest demand is known as the peak. New England's last remaining coal fired power plant is being paid to be available to meet that peak.

Peak electricity is expensive, affecting power supply costs and in turn, customer bills.

Peaks also impact the environment because the more inefficient and environmentally impacting generators are often used to meet the high demand for electricity. That's why RMLD has its "Shred the Peak" program (www.rmld.com/home/pages/shred-peak).

According to RMLD, the annual peak typically occurs on a hot and humid weekday afternoon from June to August between the hours of 2 p.m. and 7 p.m.

There's also a peak each month, and "in cooler months, peaks typically occur in the evening between the hours of 5 p.m. and 9 p.m."

It's important to consider when you run energy intensive appliances, particularly on those very warm or very cold days.

But it's also important to hold the power grid operator accountable to our climate goals.

To get involved, on March 30, ISO-NE is holding a quarterly meeting for ratepayers in Portsmouth, N.H., from noon to 3:30 p.m.

This is the meeting of the "Consumer Liaison Group" of ISO New England where you can ask questions and hear from a diverse panel.

You can register to join in person OR online at https://www.iso-ne.com/event-details?eventId=149757.

By Reading Climate Committee associate emerita Gina Snyder