This summer, the agencies that manage U.S. electric grids are on guard to provide adequate electrical capacity. Higher temperatures and continuing drought — in the Midwest and West particularly — may create problems for power supplies. Hot weather means more air conditioning, and drought can impact the reliability of hydropower resources. There is good news, however. More microgrids are coming online to help keep electricity flowing during peak demand periods and power outages.
Peak demand for utilities usually occurs in mid to late summer during the end of the day. That’s when daily solar production ramps down and temperatures are highest. The National Oceanic and Atmospheric Administration (NOAA) forecasts for 2022 confirm a continued increase in summer temperatures and predict ongoing drought in the western half of the U.S., both due to climate change.
The supply and demand imbalance presents a challenge for the central Midwest, California and Texas. This summer, these regions could face shortfalls in electricity or grid reserves, particularly in unpredictably long or extreme heat waves or when wildfires prevent utilities from importing power from other areas.
The Midwest faces the most significant risk of electricity shortages
In its 2022 Summer Reliability Assessment, the North American Electric Reliability Corporation (NERC) said the region at greatest risk for disruption is the Midwest, mainly the northern and central sections. The Midcontinent Independent System Operator, Inc. (MISO) “faces a capacity shortfall in its North and Central areas, resulting in high risk of energy emergencies during peak summer conditions,” NERC reported.
In its assessment of generation resources for 2022, MISO warned of a potential shortfall in “firm power” — usually defined as a fossil-fuel plant — of five gigawatts (GW) during the July peak period and three GW in August. The grid operator says that it may have insufficient generation resources to cover summer peak forecasts and require imports of wind power or temporary controlled outages even under typical conditions.
There is at least a 50% probability that summer temperatures will be above normal, particularly in the northern part of the MISO region. The Midwestern grid also faces increased demand as it undergoes summer repairs on a critical, tornado-damaged transmission line.
California’s grid manager, the California Independent Systems Operator (CAISO), announced that it, too, anticipates an energy shortfall. CAISO is not forecasting actual power outages but says the grid would be in a state of “elevated risk” if high temperatures and other unpredictable events were to occur. The 1,700 megawatt (MW) shortage that CAISO reported refers to the amount of reserve power available to ensure the reliability of California’s power grid. In its Summer Loads and Resources Assessment report, CAISO notes that 2022 is the “third consecutive year of lower-than-normal hydro capacity in California.”
Over the past few years, the state has moved aggressively to increase battery storage capacity and build out renewable energy resources to replace retiring fossil fuel plants and counteract electricity shortages.
In April of 2022, CAISO announced a new record when 97.6% of electricity on the grid came from clean, renewable energy. Also, CAISO plans on 3,000 MW of new resource capacity to go online in June from battery energy storage systems (BESS). Large, utility-scale batteries can charge during mid-day using solar and wind and re-inject power back onto the grid on hot summer evenings when demand peaks.
However, global supply chain disruptions continue to occur, and a controversial Asian anti-dumping case before the Department of Commerce threatens the supply of solar panels from Southeast Asia. The lack of solar panels has hampered solar projects across the U.S. and prompted California regulators to anticipate that up to 3,800 MW of new resources may face delays through 2025.
While renewable energy and energy storage capacity is growing fast in California, the nascent storage industry may not be ready to deliver enough installed capacity. The challenge is to meet electricity demand in the case of extreme, unanticipated weather conditions or planned retirements in the fleet of gas and nuclear power plants.
Recently, California Governor Gavin Newsom released a revised budget proposal earmarking $5.2 billion (USD) to fund a “strategic electricity reliability reserve” to bolster the state’s power resources.
Texas is also vulnerable to extreme heat this summer
The Electric Reliability Council of Texas (ERCOT) predicted a new record for peak demand in the state, spurred by increasing temperatures and continued economic and population growth. This summer, Texas is not forecasting shortages in electricity reserves, but several power plants shut down unexpectedly in May due to an unexpected heat wave. According to the Texas Tribune, ERCOT had asked several plants to delay their routine spring repairs in anticipation of hot weather. The plants went offline anyway due to equipment failures.
In anticipation of increased demand, drought and extreme heat — and in response to a disastrous winter power outage in 2021 — Texas has increased its power reserves in the past year. However, environmental conditions this summer could pose new challenges to aging plants on the Texas grid.
Microgrids counter grid vulnerability by providing resilient distributed energy systems
Major U.S. power outages have increased dramatically from a few dozen to thousands during the past two decades. As Popular Science reports, the U.S. has more blackouts than any other developed country. Our aging electric grid — much of which was built in the 1950s — is partly responsible for the blackouts, along with the increase in extreme weather events due to climate change.
In response to increased power outages, microgrids are being built. The Edison Electric Institute has reported a sevenfold increase in microgrids since 2010. Businesses, particularly critical facilities, are investing in microgrids so they can continue to operate when the grid goes down, provide vital services to their communities and cut their financial losses.
See how one coastal community designed a microgrid to provide energy resiliency to its emergency operations center in this case study.
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