The world is in flux. The climate is changing, making extreme weather like derechos and ice storms commonplace. The digital revolution continues to accelerate. Mountains of information exchanged and analyzed wirelessly and instantly; data processed by machine learning and artificial intelligence. Last-century, old models of news media structured as one-way, top-down streams are flattened. Old models of finance are changing with the rise of cryptocurrencies like bitcoin, ethereum, or dogecoin. Newsrooms are decentralized, finance is decentralized, and energy production is also being redistributed. But old-world energies, like fossil fuels, still dominate global use vs. clean energy.
Where we go in the next few years will set the course for reaching net-zero goals set out by world leaders.
Solar energy is cheaper than ever. Wind energy is ascendant. Battery storage is cheaper than ever. Coal plants are being decommissioned. Lastly, nuclear energy is being touted as a viable replacement for the baseline energy vacuum created by coal retirements.
Today, we’ll look at all these electricity sources, their impact and futures.
In 2019, coal, gas, and oil generated over 60% of electricity in the US. But they accounted for 99% of carbon dioxide (CO2) emissions. The other 1% came from other fuels like propane.
Overall, electric power generation produced about a third of the CO2 emissions in the US.
Many utilities rely on natural gas. Our planet has enormous reserves of natural gas (mostly made of methane).
To transport it, gas is converted to liquified-natural-gas (LNG). The process, liquefaction, cools the airy gas to shrink it to 1/600th of its original volume. LNG is regasified for delivery through pipelines to customers.
Natural gas is predicted to be the biggest-growing fossil fuel for the next decade, peaking by 2037.
The reason? It’s versatile and cheap. In the US, 36% of natural gas is used to generate electricity. The remaining two-thirds are used for residential, commercial, industrial, and transportation, largely for heating.
The question of emissions from burning gas is critical. Big energy claims that natural gas is a bridge fuel that will transition the world to low- or no-carbon.
Unquestionably, carbon emissions from gas are better than other fossil fuels. Natural gas is sometimes called the “clean” fossil fuel, because it produces about half the carbon dioxide emissions of burning coal.
Gas vs Coal
Every kind of coal (lignite, bituminous, etc.), despite a vigorous campaign to rebrand it as “clean,” produces more CO2 than gas. In fact, gas burns cleaner in every respect to coal, which also releases sulfur dioxide, mercury, and a dozen other toxic chemicals.
But asking whether coal is worse than gas is the wrong question. We’re rapidly approaching the end of the “bridge.” No effort is being made to limit profitable gas production. Even as the US purports to cross the gas bridge, exports of LNG have skyrocketed in the past five years. (see image LNG)
Incredibly, the US even re-exports LNG that it imported. In 2019, the US re-exported 200 million cubic feet of LNG to Japan. The UK received 300 million cubic feet, re-exported due to favorable gas pricing.
The US exports most of its LNG to Asian countries. About 2.5 billion cubic feet per day goes to South Korea, Japan, China, and India collectively.
New LNG liquefaction facilities are coming online in coastal states like Texas and Louisiana. This means LNG production is solidifying its market as a “bridge” technology.
The invisible greenhouse gas that constitutes most of natural gas is methane. Burning methane is clean compared to coal or petrol.
Drilling and fracking sites emit methane and that’s often overlooked in the “clean” gas picture painted by the industry. Some 2-3% of all gas produced is leaked into the atmosphere annually. Escaped methane and rapid growth of natural gas production has likely canceled out the emissions saved by not burning coal.
The good news is methane doesn’t last. It breaks down much faster than CO2. The bad news is that while it exists, it traps more heat than CO2. How much more depends on who you ask.
The EPA uses a 100-year conversion for measuring methane’s impact. At 100 years, methane is about 30 times worse than CO2.
But methane doesn’t last 100 years.
In the lowest part of Earth’s atmosphere, the troposphere, it lasts only 10 years. If it passes through the troposphere, it will last over 100 years in the stratosphere.
As more methane is oxidized, the amount of atmospheric hydroxyl (OH) is reduced. This depletion increases the lifespan of methane.
Using a 20-year scale to measure the impact of methane, it’s 80 times more potent than CO2.
Whether it’s from cow flatulence or emissions that occur naturally from underground, methane has always been around. But since the industrial revolution, atmospheric methane levels have doubled. (graph)
Prediction: LNG and gas production is not going away
Further discussion: How can we limit methane emissions? Is natural gas a good “bridge” fuel?
Clean or dirty, after wood, candle wax and whale oil, coal is one of our oldest and most prolific sources of fuel.
It remains cheap and relatively easy to extract.
Some countries are even betting on coal in big ways, China for example.
But also Mexico where they just announced a reversal of coal phaseouts and reactivation of a large coal mine. The move comes in the name of energy sovereignty, nationalism and nostalgia. Mexico President Andrés Obrador stopped renewable energy projects, called wind farms “fans” and “visual pollution,” and reinvigorated fossil fuel, including coal and oil. His policies gained traction when Texas barred natural gas exports during the February 2021 freeze.
Coal dust is dirty. A single train car can emit 500 pounds of coal dust on its journey from mine to burner.
Coal ash is dirty. People living within a mile of coal ash disposal sites are more likely to have cancer according to EPA records.
Coal is not going away though. It’s used for cement and steel production.
Cement accounts for 2 billion tons of carbon annually, about three times more than the aviation industry. But most of the carbon from cement doesn’t come from the fuel. It comes from the breaking down limestone into calcium oxide or lime.
Steel production also relies heavily on coal, but not exclusively. Some alternatives are being developed. In 2020, one Swedish company began making some steel free of fossil fuels. The key for carbon-less steel production is using electric arc furnaces or hydrogen. Steel accounts for about 7% of global greenhouse gas emissions.
The coal market is shrinking in the US. Since 2008, production and consumption have declined to levels not seen since the 1970s. Natural gas and renewable energy have taken up the slack.
Prediction: Removing coal from our lives makes the air and water cleaner. From the mine, to the boxcar, to the burner, to the ash disposal, every aspect of our world benefits from reducing or removing coal.
Further discussion: How long will coal use continue? When will China and other countries burn out on coal?
Clean Energy vs. Fossil Fuels: The Intermission
We’ll continue this Earth Day overview of clean energy vs fossil fuels after a message from MOXIE’s superstar salesman Kerry Batteau.
Kerry Batteau: “Call MOXIE at 855-669-4387 and get out of the carbon emissions game. “
The biggest gains in wind energy are coming in offshore developments. The US has lagged in offshore wind for a few years but that’s about to change.
Last year, Dominion Energy installed two offshore wind turbines 30 miles from Virginia Beach.
In their new wind project, Dominion is only dipping its little toe in the water. Coastal Virginia cost $300 million, but is only rated for 12 megawatts, a tiny drop in the ocean, so to speak.
By comparison, Dominion’s next project has 200 offshore turbines going up by 2026. They’ll produce about 2.6 gigawatts.
Dominion generates a third of its electricity from nuclear, a third from natural gas, and about 25% from coal. The remainder, about 5%, comes from renewables.
The key with wind and solar power, unlike hydropower, is the intermittent availability of the inputs. The sun goes down regularly, clouds interrupt, and the wind stops irregularly.
The way to accommodate these fluctuations is with a base load like nuclear, fossil-fuels, hydropower, or increasingly battery storage. In the next section, we’ll talk about how they’ll be linked to battery storage to smooth out the uneven output of wind and solar.
Prediction: Wind and solar are here to stay, grow, and develop higher efficiencies with innovations and new technology.
Further discussion: How can renewable energy adoption be accelerated? Are there any drawbacks to renewables like wind and solar?
How Clean is Nuclear Energy?
Any discussion of nuclear energy provokes the most divergent reactions of any energy form. Little disagreement can be found on natural gas, it goes up, it goes down. It makes sense. We burn it for heat or spinning a generator. We’ll quibble over the term “clean coal” but most of the research is inarguable. Coal is kind of dirty from mining to transport to firing to by-products and ash disposal. It’s also cheap and easy to comprehend.
The difference with atomic power is that the conversation evokes emotional response. It’s complicated. Nuclear is tainted by weapons and the geologic concept of half-life decay on a multi-millennial timeline. Atomic energy is clean in the sense that carbon emissions are absent. It’s frighteningly dirty in the radioactive waste, storage, and potential for creating uninhabitable zones like Chernobyl.
In 2011, Fukushima Daiichi was a massive accident without an immediate body count. The aftermath and long-term exposure to radiation tells a different, more complex, and ongoing story.
The Fukushima accident released about 1/10 the amount of radiation as Chernobyl.
But is nuclear power dangerous?
That depends on who you ask. While many technological advances have been made, even in the last decade, everyone says it’s safe until the next disaster. Then the nuclear proponents go quiet for maybe a decade (like they did after Fukushima).
The real question with nuclear power is: Do we need it to smooth out the fluctuating feed from intermittent sources like solar and wind? Or can battery storage play that role?
Again, the industry is divided on this question.
Nuclear power is expensive to install. The startup costs are higher than any other form of energy. Once it’s up and running, the fuel costs are low and the carbon emissions are the same as hydropower, wind and solar. Zero.
At that point, the only challenge is where to store spent fuel. Radioactive fuel storage at Yucca Mountain was taken off the table in 2009. Since the 1950s, over 80,000 metric tons of uranium have been created. Today, most spent fuel is stored at over 70 sites in 34 states.
Prediction: Wait and see. The future of nuclear energy depends on the perceived need for carbon-free base load electricity versus the perceived risks of disaster and radioactive leaks.
Further discussion: Is it safe? At what point will the need for “clean” nukes outweigh the potential dangers of a poison byproduct that needs to be stored for 200,000 years? Can you separate emotional reactions to nuclear from the science?
Batteries are the most obvious energy storage system. Lithium-ion batteries pack a big punch and are the dominant form.
But what are some other ways to store energy?
When wind or solar produce more than the grid needs, excess power can be converted into hydrogen for green power.
Technically not a green energy, it’s more accurate to call hydrogen a fuel transfer or storage system.
But hydrogen is inefficient. It takes about three times as much energy to produce hydrogen than the output.
Hydrogen is highly flammable but when produced with “green” techniques it’s very clean. The only byproduct of burning hydrogen is water. When produced as “blue” hydrogen, it’s not clean but at least the carbon dioxide is captured and stored.
Speaking of water, there are very simple forms of stored energy, such as pumped hydro.
When excess energy is being produced, like a sunny, windy day, the extra power can be put into “hydro.” As mentioned, hydrogen is one option. Hydropower is another.
Pumping water uphill is a way to store it for later use. The US has 40 hydro-electric pumped storage plants including 8 in California. It represents almost 95% of utility-scale energy storage in the US at about 23 gigawatts.
Globally, the total capacity for pumped storage hydro-electricity is 168 gigawatts.
Pumped hydropower is also called a gravity battery. Technically, any object could become a gravity battery if it is raised and then released to generate power, electric or otherwise.
Mechanical and heat energy storage
Like gravity batteries, energy can also be stored in potential devices like compressed air, flywheels, or thermal and chemical systems.
A battery is basically a contained chemical reaction. Lithium-ion batteries are the dominant form of battery devices. Camcorders, laptops, mobile devices, and electric vehicles rely on lithium.
In the US, there is only one site where lithium is extracted, in Nevada. In 2020, Albemarle shuttered two lithium mines due to falling demand for electric vehicle batteries. The company still owns one of the largest lithium mines in Kings Mountain, NC.
But new chemical configurations are coming to the fore.
Zinc-air batteries have potential. Traditionally, the big problem with zinc batteries is their one-time use capacity. But recently, researchers at the University of Münster in Germany developed a method to recharge zinc batteries.
Air (or specifically oxygen) is also a component in lithium-air batteries. Other new chemical combos include lithium-sulfur, magnesium-ion, and sodium-sulfur batteries. Read more about better battery technologies at this link.
Prediction: Until news battery forms are developed, lithium mining is a huge question mark.
Battery storage will continue to be expensive and have a prohibitive lifespan.
Further discussion: Are utility-scale battery farms a viable way to harden the grid? Can enough battery banks be built to become as robust as traditional base load power? What is the proper balance between battery and other base load options? Is lithium the new “oil”?
Clean Energy vs Fossil Fuels
So that’s our Earth Day showdown: clean energy vs fossil fuels. Keep in mind, this is a broad appraisal of the energy, greenhouse gases, and the geopolitical storylines at play.