Researchers have come up with a way to figure out how climate change will affect the amount and type of renewable energy available in a region.
As a result of changing weather patterns brought on by climate change, there may be more fluctuations in both the demand for electricity and the supply of solar, wind, and hydropower.
Researchers at the University of Alaska Fairbanks Geophysical Institute and in Spain came up with a way to figure out the best mix of renewable energy sources and storage needs. This method will help local energy planners.
The study was published in the journal Land in August. Uma Bhatt is the main author. She is a professor of atmospheric sciences at the Geophysical Institute.
According to Bhatt, in order to design a resilient power system and get ready for the future, society must comprehend the effects of climate change and variability on renewable energy resources.
The cities of Cordova, Alaska, in the subpolar oceanic Prince William Sound, and Palma de Mallorca, Spain, were the sites of the researchers’ studies of intermittency, power generation, and energy storage in the context of historical climate data. For each location, the researchers collected climate data spanning 60 years.
A climate that is becoming less predictable and is producing more extreme weather events can affect wind, solar, and hydropower equally. Solar power might not be as available if there were more clouds. Reduced precipitation might make hydropower less accessible. Wind power may become more readily available if winds increase.
Power grids run the risk of becoming less dependable if proper planning isn’t done as the supply of renewable energy grows.
According to David Newman, a study co-author and physics professor at the UAF Geophysical Institute, “having too high a percentage of high-variability renewable power without appropriate backup power in your system actually degrades the system’s reliability quite a bit.”
The fact that the demand for power fluctuates in unpredictable ways as the weather changes adds to the difficulty of the situation. If a backup source is not ready for use right away, a sudden drop in the availability of a renewable source, such as the wind ceasing to turn the turbines, can result in blackouts even when demand is normal.
How can it be fixed? According to Newman, you need to either eliminate the variability or have a quick way to make up for it.
The simplest and most straightforward solution is to keep fossil fuel-powered generators at the ready. When necessary, natural gas-powered generators can be started relatively quickly. Even though it is cleaner than other fossil fuel sources, it is still a fossil fuel product.
An alternative, cleaner method is to store the extra energy made from renewable sources when demand is low.
Grid-scale batteries, which can store extra energy that can be used temporarily during a large-scale power outage, have gotten better as technology has moved forward.
Hydropower with pumped storage, gravity energy storage, flywheel energy storage, and compressed air energy storage are additional storage strategies. The National Renewable Energy Laboratory explains each of these fundamentally straightforward techniques.
This is currently one of the most exciting fields of study, according to Newman.
95% of the utility-scale energy storage capacity in the US is provided by pumped storage hydropower. During periods of excess power, water is pumped from one hydropower reservoir to another at a higher elevation, raising the level of the higher reservoir. When necessary, that water is released to the lower reservoir’s generators.
Gravity energy storage entails using extra energy to lift substantial weights made of rock, sand, or gravel and leaving them suspended. When power is needed, the weights are let to fall, and the cables attached to them turn a generator.
Compared to other storage options, flywheel energy storage is typically used in small applications and for much shorter energy needs. A flywheel, a large wheel that spins freely when the motor loses power, is powered by a motor. The free-spinning wheel turns a generator, and the generator makes electricity for several minutes.
Power on a grid scale can be stored using compressed air for several days. Underground air is compressed and stored using electricity, frequently in salt caverns. When needed, the air is let out, heated until it expands, and then used to power a generator.
The authors of the research papers make an important point about their work: both the renewable energy sources that are available and climate change are complicated and depend on where you live.
In order to prepare the next generation to deal with the complex issues that are coming, Bhatt said, “We must educate them to think across disciplines because both climate and energy are interconnected complex systems.”
