The Solar Eclipse and Our Electricity Supply: Why We've Got This Covered
By Laura Wisland
The Great American Eclipse, as many are calling it, is a big deal for both committed and casual star watchers alike. On Aug. 21, starting at approximately 9:15 a.m. PT, the moon will move in front of the sun to completely block its rays, leaving a swath of people across the U.S. in eerie and fantastic darkness for about two minutes. Totality!
A total solar eclipse happens about every 18 months, but most of the time the moon's shadow appears in remote places where very few are around to witness the spectacle. The coming August eclipse will be the first in the nation's history to completely occur over the continental U.S.
Given that the U.S., and especially states like California, are using more and more solar power to meet electricity needs, the prospect of a temporary moon shadow has caught the attention of electricity grid operators as well.
California currently receives more than eight percent of its electricity from large-scale photovoltaic (PV) and solar thermal plants. The state also has more than 5 GW of small-scale PV (rooftop solar) installed—meeting approximately two percent of electricity demand—and that number is growing rapidly. So, it's not surprising that the California Independent System Operator (CAISO) is looking into the effects the eclipse will have on generation that day.
CAISO expects generation from large-scale solar plants to start dropping around 9 a.m. and be reduced by about 64 percent at the height of the eclipse (assuming it's a clear morning and potential solar generation is not already reduced by cloud cover). Output from rooftop solar systems will also drop appreciably. Once the eclipse is over, it will take about 90 minutes for solar generation to return to its pre-eclipse level.
Why the eclipse is not a problem for the grid
So, is losing all that solar energy during the eclipse a big deal for the grid? Turns out, no. Grid operators routinely plan for events where major power sources or transmission lines are lost unexpectedly because of a storm or equipment failure. The eclipse is a rare, significant reduction in solar power, but because it is predictable, it is not like an unexpected failure or shut down.
Grid operators will have a range of options at hand while the sun takes a brief vacation. Since California had a wet winter, we can ramp hydropower up and down as needed. CAISO can also use natural gas generation to provide additional grid flexibility, though that fossil power would emit greenhouse gas emissions.
However, many clean energy nerds, including me, are hoping that we can back-fill the lost solar power by harnessing the power of our own energy flexibility and using less power during the two-hour eclipse window. The California Public Utilities Commission is asking all Californians to pledge to use slightly less electricity during the eclipse to reduce the need to rely more on fossil fuels like natural gas.
From the caleclipse.org website:
"While our utilities and grid operator have all the tools necessary to manage the grid during the eclipse, what if millions of Californians stepped in to allow our hard working sun to take a break, rather than relying on expensive and inefficient natural gas peaking power plants.
The 'Do Your Thing for the Sun' campaign is an effort to engage Californians and demonstrate that when we come together to do one small thing to reduce energy usage, we can have a major impact on our environment."
Take the pledge here.
CAISO and other grid operators around the country have been planning for the eclipse for months, so rest easy and enjoy the totality. (That is, of course, unless you happen to be on a solar-powered train with no brakes, in which case you should plan accordingly.)
Laura Wisland is a senior energy analyst and expert on California renewable energy policies with the Union of Concerned Scientists.
The U.S. District Court of Appeals ruled 2-1 Tuesday saying that the Federal Environmental Energy Regulatory Commission (FERC) failed to adequately review the environmental impacts of the greenhouse gas (GHG) emissions of the fracked gas Sabal Trail pipeline, which runs more than 500 miles through Alabama, Georgia and Florida.
As ocean waters warm and acidify, corals across the globe are disappearing. Desperate to prevent the demise of these vital ecosystems, researchers have developed ways to "garden" corals, buying the oceans some much-needed time. University of Miami Rosenstiel School marine biologist Diego Lirman sat down with Josh Chamot of Nexus Media to describe the process and explain what's at stake. This interview has been edited for length and clarity.
What is killing coral?
I wish we had an easy, straightforward answer for what's killing corals. We know there are many, many different factors influencing coral abundance, diversity, distribution and health these days, but I think the specific answer varies based on where you are.
Temperatures play a major role at global scales, and then you have all of these other, more local factors like disease, physical impacts of storms, or ship groundings.
Researcher Stephanie Schopmeyer prepares to out-plant Staghorn coral onto a Miami reef. Rescue-A-Reef, UM Rosenstiel School of Marine and Atmospheric Science
We had the dredging of the Port of Miami channel a couple of years ago and that caused a lot of localized mortality due to sediment burial and sediment stress. You also have land-based sources of pollution that can damage by location and nutrient influence that causes algal overgrowth of corals.
Local factors are superimposed on regional factors directly related to global climate change. Changes in temperature, more temperature extremes, acidification of the water, changes in storm frequency and sea level rise— all are at different scales — but they all combine to cause coral mortality.
Factors vary both spatially and temporally, but the outcomes are all the same. Regardless of where you are, we've lost a tremendous amount of coral.
Nursery-raised Staghorn coral out-planted onto a reef by a citizen scientist.
In the face of all those threats, can restoration work?
Historically, restoration was developed and used for acute disturbances. A ship runs aground, and so then there's a recovery, and funds are allocated to recovering the reef structure at a given location, and then corals are planted on top of that. But as global conditions decline for coral reefs, there's now a need to scale up. So, we're not just dealing with the localized impact—we're looking at species declining throughout their range.
We need other tools at larger scales, and that's where coral reef gardening has come into play, because it works at larger scales compared to just dumping cement and rebuilding reef structures, costly endeavors that recover just a very small footprint. We're growing and planting these organisms.
Do you worry about planted coral dominating the reefs?
Initially, these techniques were developed for fast-growing corals. The genus that we're focusing on, Acropora, is threatened, so these are very important reef-building species.
When abundant, they monopolize shallow environments. They form thickets, extensive areas of high-density colonies. That's the way they used to grow, until about three to four decades ago when they got wiped out by disease and other factors. The branching corals that we're working with grow between 10 and 15 cm per branch per year, so that's very fast growth.
Through recent advances in coral aquaculture, we're now also able to grow massive species, the ones that grow very slowly. Mote Marine Lab has developed microfragmentation techniques where they can cut coral colonies very, very small and make them grow very, very fast. Although we focused on branching corals initially, now most of the programs, especially here in Florida, are expanding onto other threatened species.
Citizen scientists plant coral. Rescue-A-Reef, UM Rosenstiel School of Marine and Atmospheric Science
Can these efforts solve the problem, or are they a placeholder until climate stabilizes?
You hit the nail on the head. One of the early criticisms of reef restoration was the scale issue and spending a lot of resources working on a very small footprint.
We've dealt with that now, over the past 10 years we've expanded to the point where we're growing thousands and thousands of corals—we're planting thousands and thousands of corals—so that issue of scale is no longer a valid criticism.
The other major criticism is that, even though we're planting a lot of corals, we're planting them onto environments where the same stressors that caused their initial mortality are in place. Now there is ocean acidification and increased temperatures, so things have gotten, in some cases, progressively worse.
Staghorn corals create a sustainable source of corals for use in restoration. Rescue-A-Reef, UM Rosenstiel School of Marine and Atmospheric Science
That is a valid concern if we were just planting corals, but we're not just doing that. We're still concentrating on all of the other aspects of reef restoration, setting up marine protected areas to protect fish stocks and coral impacts, working to curb land-based sources of pollution, and setting up sedimentation and nutrient controls. And then, on a much larger scale, we're all trying to curb carbon emissions, trying to limit the greenhouse impacts and acidification impacts. All these tools just help us buy time.
We're also doing a lot of genomics work to see how corals can increase their resilience. A colleague of mine here at the Rosenstiel School at University of Miami, Andrew Baker, is stress-hardening corals. He works on coral symbiosis, and he found that by applying a little bit of non-lethal stress, he can make corals shuffle their Zooxanthellae, which are the endosymbiotic microalgae that provide energy to the corals. In that process, they're able to uptake Zooxanthellae that are more thermally tolerant. So, through the forced shuffling of symbionts, you may be able to buy these corals one or two degrees of tolerance, so that they become more tolerant to bleaching in future years. That is cutting-edge science.
We're trying to actually find out what makes corals survive, and trying to beef up their defenses and their resilience over time. And that's because we have access to all these coral genotypes through the active propagation from coral gardening.
Reposted with permission from our media associate Nexus Media.
By Karen Perry Stillerman
This job has responsibility for scientific integrity at the USDA, as well as oversight of the department's various research arms and multi-billion dollar annual investments in agricultural research and education that are essential to farmers and eaters alike.
The Center for Biological Diversity and the Sierra Club lodged formal comments with the federal government Monday opposing a massive gas fracking project that spans 220 square miles of public land in Wyoming south of Yellowstone National Park.
The Normally Pressured Lance gas field would destroy wildlife habitat and worsen ozone pollution, a major cause of childhood asthma, in areas already suffering from extreme air pollution.
Sierra received complete surveys from a record-breaking 227 schools—in 36 states, the District of Columbia, and for the first time ever, Canada.
By Andy Rowell
The decades-long struggle for social and environmental justice in the Niger Delta continues, largely unseen by the wider world.
On Aug. 11, hundreds of people from the Niger Delta stormed the Belema flow station gas plant owned by Shell in the Rivers State region of the Delta. The plant transports crude oil to the Bonny Light export terminal, from where it is shipped overseas.
The National Academy of Sciences, Engineering and Medicine said in a statement the Interior Department has directed it to cease its study on the potential health risks for people living near surface coal mines in Central Appalachia.
The Interior Department, which committed more than $1 million to the study last year, has begun an agency-wide review of grants over $100,000 because of the "Department's changing budget situation."