Renewables can never provide reliable power
While wind and solar are variable rather than constant power sources, grid operators increasingly manage this variability through storage, transmission interconnection, demand response, and diverse generation mixes, and multiple regions now run for extended periods on very high shares of renewable electricity.
What we know
The claim that renewable energy sources cannot provide reliable baseload power reflects a real technical characteristic of wind and solar, their output varies with weather and time of day, but the conclusion that this makes them unusable as the backbone of an electricity grid does not match how modern grid operators are actually managing high-renewable systems. The traditional concept of baseload power, a constant source running continuously to meet a grid's minimum demand, developed around large coal and nuclear plants that are inefficient to ramp up and down. Grid engineers increasingly argue that the relevant question is not whether any single source can provide constant baseload, but whether the overall system, combining multiple generation types, storage, and demand management, can reliably meet demand at every hour.
Several grids already demonstrate high renewable penetration in practice. South Australia has run its grid on renewable sources, primarily wind and solar, for over 100 percent of demand during some periods, exporting surplus power, and averaged over 70 percent renewable generation annually in recent years according to the Australian Energy Market Operator. Denmark generates the equivalent of more than half its annual electricity from wind alone, and its grid remains among the most reliable in Europe according to Council of European Energy Regulators data. Germany, despite its higher electricity costs from other factors, sourced more than half of its electricity from renewables in 2023, according to the Fraunhofer Institute for Solar Energy Systems.
Grid stability with high renewable shares depends on several complementary tools. Battery storage, led by lithium-ion installations but increasingly supplemented by longer-duration technologies, can store excess solar generation for release during evening demand peaks; California's grid operator reported that battery storage played a major role in preventing blackouts during heat waves in 2022 and 2023. Pumped hydro storage, the largest form of grid-scale storage globally by capacity, has served this load-shifting role for decades in many countries. Transmission interconnection between regions allows power to flow from areas currently generating surplus wind or solar to areas with a temporary shortfall, smoothing out local variability. Demand response programs pay large consumers to reduce usage during shortage periods, and diverse renewable portfolios combining wind, solar, and hydro in different geographic locations reduce the chance that all sources underperform simultaneously.
Remaining gaps, particularly during multi-day periods of low wind and low sun, are currently addressed in most grids through a mix of natural gas peaker plants, existing nuclear and hydro capacity, and growing battery and long-duration storage deployment. The International Energy Agency's modeling for net-zero pathways assumes this combination approach rather than proposing renewables can or should operate in total isolation from other flexible resources in the near term.
The baseload framing itself is increasingly viewed by energy analysts as outdated, since it was designed around the operating constraints of older thermal power plants rather than being a fundamental physical requirement of electricity grids, and newer grid designs built around flexibility and diverse resources can achieve high reliability with a much larger renewable share than the baseload framework would suggest is possible.
Common claims
- Wind and solar are too intermittent to power a modern gridMisleading - with storage and grid management, high renewable shares are achieved today
- We need fossil fuels for baseload powerContested - baseload can be provided by storage, hydro, geothermal, and demand response
- 100% renewable electricity is technically impossibleContested - NREL finds it technically achievable but challenging; last 10% requires innovation