A recent edition of yale 360 addresses the lies, distortions, and half-truths surrounding the question of whether renewable energy can provide a reliable source of electricity at all times, or whether it requires “base load” thermal generation capacity to be reliable. We all vividly remember the so-called governor of Texas foaming at the mouth after a severe cold snap knocked out that state’s power grid in 2021. He blamed the problem on the state having too much renewable energy.
Amory Lovins, professor of civil and environmental engineering at Stanford University and co-founder of the Rocky Mountain Institute, debunks those misconceptions with a tool that is freely available to everyone: data. He uses it to debunk 3 myths about renewable energy and the grid.
Myth #1: A grid based on renewable energy is unreliable
Lovins says the indicator most often used to describe network reliability is the average duration of power outage experienced by each customer in a year, a metric known as System Average Interruption Duration Index, or SAIDI, Germany. is often cited as an example of a country with an unstable network. It gets about half of its electricity from renewable sources. However, its grid is one of the most reliable with a SAIDI of just 0.25 hours in 2020. The United States, where renewable energy and nuclear power each provide about 20% of electricity, had a rate of cuts 5 times higher than that of Germany: 1.28 hours in 2020.
Since 2006, Germany’s renewable share of electricity generation has almost quadrupled, while its rate of power outages has almost halved. Similarly, the Texas grid became more stable as its wind capacity increased sixfold between 2007 and 2020. Today, Texas generates more wind power, about one-fifth of its total electricity, than any other state in the United States. US data shows that renewables increase grid reliability, despite what the oil and gas lobby would have us believe.
Myth #2: Fossil fuels are needed to stabilize the grid
Once again, the data disproves this popular myth. Between 2010 and 2020, Germany’s generation from fossil fuels decreased by 130.9 TWh and nuclear generation decreased by 76.3 TWh. These declines were offset by 149.5 TWh of renewable energy. Another 38 TWh were saved thanks to energy saving strategies. As we saw earlier, through all these changes, the network in Germany became more stable, not less. By 2020, Germany’s greenhouse gas emissions were reduced by 42.3% below 1990 levels, exceeding the 40% target set in 2007. Carbon dioxide emissions from the power sector alone were reduced from 315 million tons in 2010 to 185 million tons in 2020.
In Japan, following the multi-reactor meltdowns at Fukushima, more than 40 nuclear reactors were shut down permanently or indefinitely without materially increasing fossil fuel generation or greenhouse gas emissions, Lovins reports. Electricity savings and renewable energy made up for virtually all of the loss, despite policies that phased out renewables.
Myth #3: Renewable energy cannot meet demand 24/7
This is a favorite topic of the Faux News crowd and a disgraced former president and is pure grade A nonsense. Lovins points out that ALL generating sources are offline some of the time, whether it’s for weather emergencies or maintenance of routine. None operate all day, every day, all year long. All electrical power sources will not be available at one time or another.
Network administrators have to deal with that reality, just as they have to deal with fluctuating demand. The entry of large amounts of renewable energy does not change that reality, even if the ways in which they deal with variability and uncertainty are changing.
Hydroelectric power fluctuates with the amount of water available. Coal and methane supplies are not 100% reliable. Many of the blackouts in Texas in 2021 were due to diesel generators using the power lines refusing to start. French nuclear facilities were shut down for 96.2 days on average in 2019 due to “planned” or “forced unavailability”. That increased to 115.5 days in 2020. After a blackout in northeastern US states in 2003, abrupt nuclear generator shutdowns caused nine reactors to produce almost no power for several days. Many required two weeks to return to full production.
Modern grid operators (except in Texas, where grid operations are based on ideology rather than data) emphasize diversity and flexibility rather than nominally stable but less flexible “base load” generation sources. Diversified renewable portfolios do not fail as massively, enduringly or unpredictably as large thermal plants do. All thermal generating plants are offline 7 to 12% of the time, says Lovins.
The mission of a grid
The purpose of an electrical grid is not just to transmit and distribute electricity as demand fluctuates. It also has to manage the intermittency of traditional fossil and nuclear power plants. In the same way, the grid can quickly support wind and solar variations with other renewable energy, a task made easier by more accurate forecasting of weather and wind speeds. That, in turn, allows better prediction of the production of various renewable energy sources.
Local or on-site renewables are even more resilient because they largely or entirely bypass the grid, where nearly all power outages begin. Modern power electronics have run South Australia’s billion watt grid on just sun and wind for days on end, no coal, no hydro, no nuclear power and only 4.4% power generation. natural gas required by the network regulator. Hornsdale battery supplied by Tesla has played an important role in making this possible.
battery bypass
Energy storage, whether by batteries, compressed air, hydraulics, or other means, is a common theme in CleanTechnica. There is a general belief that the transition to renewable energy depends on it. But there are less expensive, carbon-free ways to deal with variable renewables besides giant batteries, Lovins suggests.
First and foremost is energy efficiency, which reduces demand, especially during peak usage periods. Buildings that are more efficient need less heating or cooling and change their temperature more slowly so they can run longer at their own thermal capacity and therefore maintain comfort with less energy, especially during periods of peak load.
A second option is demand flexibility or demand response, which allows utilities to compensate customers who reduce the amount of electricity they use when requested. This is usually done automatically and unnoticeably. new technology like smart switch panels you can allow this to happen automatically with little perceptible effect on clients. Many online EV chargers can also adjust the amount of electricity they deliver or shift charging times to off-peak hours when demand on the grid is low.
A recent study found that the US has 200 gigawatts of cost-effective load flexibility potential that could be realized by 2030. Indeed, recent power outages in California highlight the need for demand response, prompting the California Utilities to create the Emergency Load Shedding Program to build on previous demand response efforts.
Another option for stabilizing the grid as renewable energy generation increases is diversity, both geographical and technological: onshore and offshore wind power, solar panels, solar thermal, geothermal, pumped hydro, municipal, industrial or agricultural. There are even new ideas like vertical bifacial solar panels Y offshore floating solar to complete renewable energy portfolios. The idea is simple: if one of these sources, in one place, is not generating electricity at any given time, it is likely that others are.
Vehicle-to-grid technology could become an important part of the grid stabilization process. Ford is already sparking a spike in interest in V2G because it has partnered with Sunrun to promote the idea to drivers of its F-150 Lightning electric pickup truck. Simulations show that air conditioning with ice storage in buildings plus smart charging to and from the grid using electric vehicles could make it possible for Texas to use 100% renewable electricity by 2050 without needing any storage battery at all.
Even Europe, famous for its cold, dark winters, may only need storage for a few weeks, based on the experience of several German and Belgian utilities. That’s a much more feasible challenge than many fossil fuel supporters like to believe is possible.
Food to go
The bottom line is simple, says Lovins. “Power grids can handle much larger fractions of renewable energy at little or no cost. Some European countries with little or no hydropower already get half to three-quarters of their electricity from renewables with better grid reliability than in the US It’s time to bust the myths.” Amen to that. Let the data speak, not the harbingers of doom that are primarily concerned with lining their pockets, to hell with the environment.
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