Grid Reliability, Resiliency, and Baseload Power: U.S. Realities and Risks

Grid Reliability, Resiliency, and Baseload Power: U.S. Realities and Risks

Grid reliability refers to the ability of the regional power grid system to react to changes in power demand without compromising good service and availability, “to deliver electricity in the quantity and with the quality demanded by users.” A related but different concept, grid resiliency, refers to the ability of the grid to bounce back quickly from unexpected disruptions, (often cyber incidents whether planned attacks or accidental software bugs) and adapt. Grid resiliency improves overall grid reliability. Typically, it is baseload power that provides the most reliability. Baseload power is power which can be accessed reliably and quickly when needed without disruptions. Intermittent power sources like wind and solar can only provide baseload power at certain times of the day and even then not reliably so. Utility-scale battery storage and distributed energy resources (DER) can also increase grid reliability when used strategically. 

EPA Chief Scott Pruitt, fresh from a conference of coal executives, has recently said that coal plants are necessary in the U.S. to ensure grid reliability, pointing to the necessity to have solid fuel on-site in the event of unforeseen demand. However, in some regions studies have indicated otherwise. In the PJM power market which encompasses 13 states and 21% of U.S. GDP, a recent study indicated that grid reliability could be ensured with 86% gas power and probably more. The current level there is only 33% gas power. Increased natural gas generation can increase the reliability of wind and solar on the grid by providing quick-start back-up generation when needed. The study did indicate however that grid resiliency could be affected. The PJM market encompasses or is adjacent to the Marcellus and Utica shale fields and there are multiple sources of gas to meet demand as well as a flexible electric transmission system that can move power where needed quickly if warranted. This contradicts Pruitt’s assertion, at least for that area. Pruitt raised concerns about over-reliance on natural gas and suggested that an attack on gas infrastructure could cripple the grid. The Trump administration recently ordered a review of U.S. baseload power by the Dept. of Energy focusing on potential grid reliability effects of renewables. Most analysts consider that penetration of intermittent renewables on the grid are nowhere near the degree that would affect reliability although California could face such issues at some point. State subsidization of some nuclear plants and a few coal plants is also going forward with preservation of grid reliability being the main concern. Although some are concerned that renewable subsidies are responsible for retirement of coal and nuclear, most utility execs say it is really cheap natural gas and stagnated electricity demand. Since nuclear is clean energy there is more incentive to keep them on-line even at a loss. FERC recently held a conference focusing on power reliability and wholesale power market fundamentals in light of renewables mandates and state subsidization of nuclear. At issue is potential conflict between state power policies and wholesale power markets. Some favor a mixed market approach, possibly with subsidized and unsubsidized generation auctioned differently. Variable state policies make it more difficult to integrate with regional power markets. There are a few regional approaches such as the Regional Greenhouse Gas Initiative which is essentially a nine-state cap-and-trade system. Indeed at the FERC conference some stressed the need to be able to price carbon emissions as it would lead to market stability. While subsidization of nuclear will likely affect market functioning it also provides carbon-free energy as well as fuel diversity.

Baseload power varies by region. PJM is planning for gas to be the dominant baseload power in the near future. The state of Illinois gets more than half of its electricity from nuclear plants which provide carbon-free baseload power. Germany was using nuclear for baseload but now employs renewables, distributed sources, lignite coal, and biomass for some baseload power. The Upper Midwest is adding more access to gas through Rover and other pipelines coming from Appalachia. California, which currently consumes 1/8 or 12.5% of U.S. gas production, is set to become more dependent on renewables and storage and gas use for electricity is dropping. Some of the big recent drop in gas use in 2017 is from increased hydro output due to the rivers being recharged with rain. Due to the Alisa Canyon gas storage field being offline for injection California is facing potential problems with grid reliability in the event of unexpected demand increase. They currently have aggressive renewables and storage mandates. Half of solar is distributed solar and so has some potential for grid balancing during peak daylight hours there. In contrast the PJM market has very low penetration of DERs so more as planned can only help grid resiliency. More coal plant retirements in the Midwest could theoretically effect grid reliability but that is less likely with more transmission pipelines headed that way. Midwest grid operator MISO is modeling demand response for a once-in-a-decade demand event. The Southeast is also in the process of assuring gas supply for new gas plants with several large pipelines including Mountain Valley, Atlantic Coast, and Atlantic Sunrise. There is also some renewables buildout there. The new secure gas supplies will aid fuel assurance and grid reliability. The Northeast may be short on gas as some pipelines have been delayed indefinitely. Thus coal and oil plant retirements and planned nuclear plant retirements may also have to be delayed. Typical winter spikes and Canadian gas imports are likely to continue until more gas supplies are secured. Williams’ Transco – Northeast Supply Enhancement project has been proposed to add about 400 MMCF/day of new supply capacity for New Jersey and New York City and with much of that being bottleneck relief in Pennsylvania and New Jersey so that New York’s current anti-pipeline bent won’t likely be triggered while air quality in New York City continues to improve by replacing fuel oil with natural gas. That project is hoped to be in service by winter 2019-2020.  

A less common and quite temporary issue in confronting grid reliability includes planning for a full solar eclipse on grids that are heavily solar powered. California’s ISO is currently doing just that in anticipation of the August 2017 eclipse. They expect to buy more regulation services prior to the eclipse. Europe, with high solar penetration on the grid was able to maintain grid reliability during the March 2015 total eclipse there.

Update: Iowa GOP Senator Chuck Grassley whose state electric power is 35% wind just criticized the 60-day DOE review of grid reliability as 'predetermined' in conclusion to show a need for both unprofitable nuclear plants and unprofitable, polluting, and carbon-emitting coal plants. He and others seem to be suggesting that this could be a predetermined justification for Trump's campaign promises to revive the ailing coal industry.

References:

Webinar: Super Power: Will New Gas-Fired Power Plants Solve the Appalachian Shale Gas Glut?
May 4, 2017

EPA Chief Pruitt: Coal Plants Necessary to Ensure Grid Reliability – by Robert Walton, in Utility Dive, May 5, 2017

Nuclear Plants Account for More than Half of Electricity Generation in Illinois – by Energy Information Administration, in Today in Energy, May 5, 2017

PJM Says More Natural Gas Power Generation Would Not Hurt Reliability – by John Hurdle, in (Pennsylvania) State Impact (Energy.Environment.Economy), March 30, 2017

California ISO Preps Solar-Heavy Grid for Total Eclipse This Summer – by Peter Maloney, in Utility Dive, May 8, 2017

Emergency DR in the Midwest, California’s Grid Plans, and Earnings from Silver Spring and EnerNOC – by Jeff St. John, in Green Tech Media, May 12, 2017

California Electricity Mix in 2017 Has Involved More Renewables, Less Natural Gas – in Energy Information Administration, Today In Energy, May 17, 2017

New Video Provides Northeast Supply Enhancement Project Overview – in PipeUp, The Williams Blog, May 15, 2017

Updated: Perry Orders DOE Review of Clean Energy Impact on Baseload Generation – by Gavin Bade, in Utility Dive, April 17, 2017

Anxiety Common, Consensus Elusive Over Power Market Reforms at First Day of FERC Conference – by Gavin Bade, in Utility Dive, May 2, 2017

What is the Difference Between Reliability and Resilience? – by Aaron Clark-Ginsburg, Stanford University (ics-cert.us-cert.gov)

GOP Sen. Grassley Questions DOE Baseload Review in Letter to Perry - by Robert Walton, in Utility Dive, May 18, 2017