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Please let us know if you have feedback<\/a>.<\/p>\n As electricity demand grows, alongside wind and solar\u2019s share in the U.S. energy mix,\u00a0concerns about renewables\u2019 reliability are being raised more frequently \u2014 including at the highest levels of the federal government.<\/p>\n \u201cWith the electricity grid, you have to match supply and demand in every moment in time,\u201d Energy Secretary Chris Wright said recently <\/a>on Fox News. \u201cWith wind and solar, you don\u2019t know when they\u2019re going to be there, and you don\u2019t know when they\u2019re going to go away.\u201d<\/p>\n Wright went on to say the development of renewables has led to an \u201cextra distribution grid\u201d that has raised energy prices.\u00a0<\/p>\n But utility planners, grid operators and analysts say wind, solar and batteries are an important part of an evolving power system in which intermittent resources can be reliably scheduled and called upon using sophisticated software and other tools. <\/p>\n They also point to both the levelized cost of electricity for renewables and their competitiveness in automated energy markets that select the least cost units to run in each hour.<\/p>\n \u201cSystem operators don’t decide whether resources bidding into the market are good or bad,\u201d said Rob Gramlich, president of energy sector consultant Grid Strategies, in an interview.<\/p>\n \u201cThere is no central decision maker,\u201d he said. \u201cMarkets don’t play favorites.\u201d<\/p>\n ERCOT\u2019s multi-resource price-selected portfolio for Aug. 20, 2025, at 5:50 PM CDT<\/p>\n ERCOT “dashboard” [jpg]. Retrieved from dashboard<\/a>.<\/p>\n \u00a0<\/p>\n With generators retiring, demand rising, and construction, financing, permitting and supply chain challenges growing, operators<\/a> and analysts acknowledged concerns over the future of the U.S. power system.\u00a0Many called for diversification of resources, including renewables and storage, to protect electricity reliability and affordability.<\/p>\n \u201cThe objective of planning is a portfolio of diverse resources at the least cost possible to avoid outsized impacts from any single one,\u201d said Michael Eugenis,\u00a0Arizona Public Service\u2019s director of resource planning.<\/p>\n APS is pursuing renewables alongside more natural gas to\u00a0maintain reliability in its territory, he said.\u00a0<\/p>\n \u201cThat is not the same as a second set or a shadow set of resources,\u201d he added.\u00a0<\/p>\n Automated markets are selecting renewables<\/p>\n One of the major concerns cited by Wright and others is the intermittent nature of renewables and the impact of that on grid reliability. <\/p>\n One of the ways grid operators measure reliability is using a metric called effective load carrying capability, or ELCC.\u00a0<\/p>\n ELCC is a complex calculation based on comparing what portion of a resource’s nameplate capacity it produces on average in simulations of decades that include factors that cause it to vary, like performance, supply and demand. For fossil resources, variabilities are caused by things like maintenance outages and fuel supply issues. Weather variations impact wind and solar.<\/p>\n ELCCs vary by region and by each system\u2019s portfolio makeup, but nuclear power generally has the highest ELCC, meaning on average over the years, it produces the closest percentage of its nameplate capacity.\u00a0<\/p>\n In the PJM Interconnection, the country\u2019s largest grid, nuclear was assigned an ELCC of 95% in its most recent auction<\/a>.\u00a0<\/p>\n Fixed-tilt solar had the lowest at 8%, and tracking solar was 11%. Onshore wind was 41%, offshore was 69%; storage was between 50% and 72%; gas was between 60% and 78%, and coal was 83%.\u00a0<\/p>\n \u201cSystem operators don’t decide whether resources bidding into the market are good or bad … Markets don’t play favorites.\u201d<\/p>\n Rob Gramlich<\/p>\n president of Grid Strategies<\/p>\n But despite their relatively low ELCCs, automated markets are consistently choosing renewables over other resources because they are cheaper at the time the grid needs them.<\/p>\n \u201cThe automated market mechanisms use all the relevant variables that affect load to pick the cheapest resources,\u201d said Richard Doying, Grid Strategies vice president and a former executive vice president for market and grid strategy for the Midcontinent Independent System Operator. <\/p>\n Those resources are bid out, and \u201cthen the next cheapest resources, and so on,\u201d Doying said.\u00a0<\/p>\n \u201cThe markets are selecting wind and solar despite their low ELCCs and low capacity values because the return justifies the investment,\u201d he added.\u00a0<\/p>\n When they are both generating at the same time, renewables are often cheaper than fossil fuel power.<\/p>\n One reason for this is that the fuel and maintenance costs for fossil-based resources are significant, continuous and volatile. Natural gas prices, for example, have nearly doubled since 2024, but are still lower than they were in 2022 following Russia\u2019s invasion of Ukraine.<\/p>\n The fuels for wind and solar are cost-free, maintenance outage costs are significantly less, and the capital expenditures to build projects are typically amortized over 20 years.<\/p>\n \u201cIf natural gas was the cheapest option to meet the peak, the markets would select it,\u201d said Sean Kelly, co-founder and CEO of forecast provider Amperon and a former energy analyst.\u00a0<\/p>\n When the sun\u2019s not shining<\/p>\n Kelly said today\u2019s advanced load and weather forecasting enhances the reliability of a resource portfolio with a high renewables penetration.\u00a0<\/p>\n While good forecasting can alleviate much of the need for backup generation, he said, rising demand for power will likely require more firm generation to fill the gaps when there is no sun or wind.<\/p>\n The ability to choose the cheapest available power source in real time is why grid operators say renewables are an important part of the same, increasingly flexible power system \u2014 not a separate system.<\/p>\n \u201cWe don’t have different systems; we have a portfolio of resources and capabilities that meet the needs of the system,\u201d said Mark Rothleder, senior vice president and COO for the California Independent System Operator, in an interview.\u00a0<\/p>\n California has one of the highest renewables penetrations in the United States. California also has some of the highest electricity rates.\u00a0Some observers link those to things to argue that renewables drive up energy costs.<\/p>\n CAISO\u2019s multi-resource price-selected portfolio for August 20, 2025, at 4:05 PM PDT<\/p>\n CAISO. (2025). “dashboard” [jpg]. Retrieved from dashboard<\/a>.<\/p>\n \u00a0<\/p>\n But other states with high levels of renewable power have comparatively low rates compared to the national average.\u00a0<\/p>\n In Iowa, for example,\u00a0wind turbines generated 59%<\/a> of the state\u2019s electricity in 2023, according to the U.S. Energy Information Administration. Iowa was also in the 10 states with the lowest average electricity price that year.\u00a0<\/p>\n While solar and wind are not always available locally when demand is high, storage penetrations are rising and some states are moving toward more regional energy markets where cheaply-produced energy from renewables can be more easily traded across state boundaries.<\/p>\n The New York Independent System Operator<\/a>\u00a0said in a recent report that although \u201cduration-limited\u201d generators like wind and solar require standby resources when the availability of the renewable fleet diminishes,\u00a0\u201cno generating type operates at full power, full time.\u201d<\/p>\n Thinking of resources as either intermittent or backup oversimplifies the complexity of the grid, experts said.\u00a0<\/p>\n \u201cWind and solar don\u2019t have to produce 100% of the time because people aren’t consuming all available electricity 100% of the time,\u201d said Beth Garza,\u00a0a senior fellow at the R Street Institute think tank and former ERCOT market monitor CEO.<\/p>\n \u201cIt is easy to vilify solar and wind,\u201d Garza said. But regardless of the resource mix, \u201cthe average electricity load is only about half the peak demand.\u201d <\/p>\n When demand peaks <\/p>\n Power systems have long been required to have reserve margins over the highest expected peak demand, and the growth of wind and solar has not changed that, said Julia Matevosyan,\u00a0an associate director and chief engineer with the Energy Systems Integration Group and a former ERCOT planning engineer.\u00a0<\/p>\n But advancements in software and market shifts have democratized incentives for energy production, conservation and storage in ways that can smooth demand peaks and deploy resources as needed.\u00a0<\/p>\n This flexibility can\u00a0optimize wind, solar and batteries to deliver low cost electricity more reliably than \u201ca more limited set of traditional resources,\u201d\u00a0Matevosyan said.<\/p>\n Over the summer, California deployed what some advocates have called the largest virtual power plant in the world when several aggregators discharged 539 MW of average output from more than 100,000 customer-sited batteries during peak demand\u00a0between 7 and 9 p.m.<\/p>\n A Brattle Group study of the deployment\u00a0commissioned by Sunrun and Tesla Energy, both of which participated in the VPP program, concluded that it could reduce the need for gas peaker plants and potentially save ratepayers $206 million between 2025 and 2028.<\/p>\n Ryan Hledik, one of the report\u2019s authors, said the VPP makes better use of assets that have already been deployed.<\/p>\n \u201cThere are a growing number of examples of VPPs scaling faster and at a lower cost than conventional resources,\u201d Hledik said.\u00a0<\/p>\n MISO\u2019s multi-resource price-selected portfolio for August 20, 2025, at 5:50 PM EST<\/p>\n MISO. (2025). “dashboard” [jpg]. Retrieved from dashboard<\/a>.<\/p>\n \u00a0<\/p>\n Renewables continue to dominate new generation as demand rises<\/p>\n Demand is rising for the first time in two decades. Last year, the U.S. used more electricity than ever before, and the EIA projects demand to grow more than 2% per year<\/a>\u00a0until at least 2026. Farther out, the predictions vary widely and are highly dependent on the growth of data centers, electrification and manufacturing.<\/p>\n The vast majority of new generation resources coming online now are renewable, with solar in the lead, followed by wind. In the first seven months of 2025, solar accounted for over 16 GW of the 21.5 GW added to the U.S. power system. Wind accounted for almost 3.3 GW and natural gas for 2.2 GW, the September Federal Energy Regulatory Commission Infrastructure Update<\/a>\u00a0reported.<\/p>\n Federal tax credits and other incentives that are being phased out boosted renewable development. But experts say even without that support, the economics are also in renewables\u2019 favor.\u00a0<\/p>\n \u201cWind and solar don\u2019t have to produce 100% of the time because people aren’t consuming all available electricity 100% of the time.\u201d<\/p>\n Beth Garza<\/p>\n senior fellow at R Street Institute and former ERCOT market monitor CEO.<\/p>\n The levelized cost of electricity for utility-scale solar and onshore wind remain \u201cthe most cost-effective forms of new-build energy generation on an unsubsidized basis,\u201d according to\u00a0Lazard analysis<\/a>.\u00a0Calculating a technology\u2019s<\/a>\u00a0LCOE involves its capital cost, fuel cost, capacity factor, and other values that vary by location and time.<\/p>\n Recently, renewable trade groups have warned of a slowdown in the solar industry. But alternative resources, like natural gas, face their own challenges, from lengthy planning and approval processes to rising fuel prices and years-long equipment backlogs.<\/p>\n \u201cThe newest, most efficient natural gas peaker plants are expensive to build and are likely to become more expensive to run because of competition for natural gas,\u201d Garza said.\u00a0\u201cThe market\u2019s answer to load growth is still to build more wind, solar, and batteries because they are the cheaper and faster to build.\u201d<\/p>\n Michelle Solomon, a manager of electricity policy at Energy Innovation, offered a similar observation.\u00a0<\/p>\n Utility\u00a0planning models \u201chave largely been choosing wind and solar and batteries for several years,\u201d she said. \u201cA diverse set of resources is most likely to be the cheapest portfolio.\u201d<\/p>\n PJM\u2019s multi-resource price-selected portfolio for August 20, 2025, at 6:00 PM EDT<\/p>\n![\"resource](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2025\/10\/Z3M6Ly9kaXZlc2l0ZS1zdG9yYWdlL2RpdmVpbWFnZS9VRC0yX3N5c3RlbXNfLTMtMDgtMjAtMjAyNS5qcGc=.webp.webp\"\/)
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