Why is Natural Gas considered the key to a Carbon-Free Economy?

Nowadays we're experiencing a very fast-changing world. Exponential organizations, disruptive economy, Massive Transformative Purpose have been dominating our?daily routine.

In the energy market, profound changes are expected to?happen by 2030, especially promoted by new storage technologies, where they will support the fast-growing?clean energy source market. Until that?day comes, we'll still have to count on fossil fuels to generate the world's majority base energy demands. That's the main reason we?cannot turn the key from a fossil fuel-dependent economy to a carbon-free society so fast.

From 1,000 BC until today, fossil fuels have been extensively used to support human activities.

A brief history of Energy ...

To generate?electricity. biomass was the primary source until the industrial revolution when coal started to replace biomass (firewood). By 1961 coal had become the major fuel used to generate electricity.

Coal plays a vital role in electricity generation worldwide and, until today Coal-fueled power plants currently power 37% of global electricity and, in some countries, coal fuels power plants have a higher percentage of the electricity market.

Until today, unbelievably coal is still being used worldwide, despite all the damages caused to the environment beyond its undeniable effect on climate change, air quality for instance.

Gradually we're changing the coal and oil energy source to natural gas.

Natural gas is often described as a “clean burning” because it produces fewer undesirable by-products per unit of energy than coal or petroleum. Like all fossil fuels, its combustion emits carbon dioxide, but at about half the rate of coal per kilowatt-hour of electricity generated. It is also more energy-efficient. On average, a typical coal-burning power plant in 2013 was about 33% efficient in converting heat energy into electrical power. A gas-fired plant was about 45% efficient. And in natural gas combined-cycle power plants - in which waste heat from a natural gas turbine is used to power a steam turbine - generation may be as much as 65% efficient. Every couple of years, the improvements that were made on the gas turbines' technology mean a considerable increase in the energy?efficiency rate.

Cleaner burning than other fossil fuels, the combustion of natural gas produces negligible amounts of sulfur, mercury, and particulates. Burning natural gas does produce nitrogen oxides (NOx), which are precursors to smog, but at lower levels than gasoline and diesel used for motor vehicles. DOE analysis indicates that every 10,000 U.S. homes powered with natural gas instead of coal avoid the annual emissions of 1,900 tons of NOx, 3,900 tons of SO2, and 5,200 tons of particulates. Reductions in these emissions translate into public health benefits, as these pollutants have been linked with problems such as asthma, bronchitis, lung cancer, and heart disease for hundreds of thousands of Americans.

Natural Gas: From Well to Power. What Does Happen?during?the whole supply chain?

One of the least understood impacts of natural gas development is its impact on the water cycle.?We often hear about how much water is required to hydraulically fracture a well (as much as five million gallons) and how much of the water (as much as 80%) stays underground.?Many think this water is irretrievably lost, that is to say, forever removed from the water cycle because we are leaving it a mile or more underground.?This is true, up to a point, but it’s far from the full story because the combustion of natural gas yields water vapor that goes into the atmosphere and lots of it.?It yields enough water to more than replace what is lost in just a matter of months.?It’s all a matter of chemistry – the kind we learned in high school.?If you weren’t paying attention in class, you might find the whole idea fantastic,?as some of our anti-gas friends do, but it’s about as basic as it gets, and, yes, fire can produce water!

Natural gas is largely methane (CH4), a naturally occurring compound of carbon and hydrogen.?When it burns, these elements recombine with oxygen to create carbon dioxide and water, two essential ingredients for life.?Elmhurst College?describes what happens as follows (emphasis added):

A simple combustion reaction is given for methane. The combustion of methane means that it is possible to burn it. Chemically, this combustion process consists of a reaction between methane and oxygen in the air. When this reaction takes place, the result is carbon dioxide (CO2),?water (H2O), and a great deal of energy. The following reaction represents the combustion of methane:

CH4[g] + 2 O2[g] ==>?CO2[g] + 2 H2O[g] + energy

Natural Gas Combustion Reaction

One molecule of methane, (the [g] referred to above means it is gaseous form), combined with two oxygen molecules, react to form a carbon dioxide molecule,?and two water molecules are usually given off as steam or water vapor during the reaction, the energy trapped inside this water vapor can also generate electricity as well.

Natural gas is the cleanest burning fossil fuel. Coal and oil, the other fossil fuels, are more chemically complicated than natural gas, and when combusted, release a variety of potentially harmful air pollutants. Burning methane releases only carbon dioxide?and water.?Since natural gas is mostly methane, the combustion of natural gas releases fewer byproducts than other fossil fuels. And remember when burned, methane generates almost 60% less carbon dioxide than coal and oil (on average) to produce the same amount of energy.

Because this is a chemical reaction, it is also possible to quantify the amount of water produced when methane is burned.?The?U.S. Department of Energy describes the process as follows:

When one molecule of methane is burned, it produces two molecules of water vapor.?When moles are converted to pound/mole, we find that every pound of methane fuel combusted produces 2.25 lb. of water vapor, which is about 12%?of the total exhaust by weight.

How much water is produced from the combustion of natural gas compared to the water required to develop it??That’s easy to calculate, given what we know about the chemistry involved.?A typical natural gas well, as noted above, will require five million gallons of water to develop.?If we assume 80% of that stays underground, there is a total of four million gallons removed from the water cycle.?That same well can be expected to produce as much as two billion cubic feet of gas over 10 years.

What we can say for now is simply this – natural gas doesn’t consume water but, rather, it generates it.

Understanding the Greenhouse Effect

Life, as we know, could only be sustained, and kept thanks to a thin layer of air surrounding our planet Earth - the atmosphere. This layer had not always been with the same composition we have today. Earth's evolving planet had to suffer a terraforming?process, as we call it today, which is the long and complex chemical reactions to continuously prepare a planet to all evolutionary stages?until we got where?we are right now.

Earth is the only planet that has all the conditions to support life in the same stage and level as we have.

Today, the atmosphere has the following composition:

The greenhouse effect was crucial for our life. Without these gases, the?average?surface temperature would be -18oC. The announced average global temperature in 2017 was 14,9oC, which means the greenhouse effect was capable to?add heat to raise the temperature to 32,9oC. It's an incredible global blanket for sure.

As you can notice,?Carbon dioxide (CO2) has less than 0,1% of all atmospheric gases but, for climate purposes, the concentration and its potential for trapping heat are more than sufficient to warm the planet, known as the Greenhouse effect. Although?CO2?is by far the most present greenhouse gas in the atmosphere, it?isn't the only one.

Today, the greenhouse gases are represented by the following graphics: ?

The greenhouse effect isn't produced only by these gases. Water vapor has also a key role in the overall greenhouse effect, especially after the year 2000, with the continuous rising of the average global temperature?(*For each 1 degree Celsius of warming, the air’s holding capacity for water vapor goes up by almost 7%).

Why should We Use (burn) Methane as a choice transition fuel source to a Low-Carbon Economy?

First, everyone should realize that Methane has twenty-eight times the potential of carbon dioxide in warming the planet. That's why we should use (burn) methane as a fuel, instead of letting it escape into the atmosphere.

Enteric fermentation from domestic livestock (cattle, sheep, goats, porks), manure management, intensive agriculture, treatment of wastewater, and landfills correspond to more than?55% of methane emissions on a global average.

In Brazil, landfills are responsible to release an equivalent carbon dioxide amount of 7 million cars/ year.

We need to create ways to collect, store and find a mechanism to use it as fuel to power plants, industrial facilities, or for domestic uses, as a source for heaters. Methane from landfills can also be used as fuel for trucks and other vehicles.

The use of?Landfill?gas depends primarily on gathering, processing, and treating methane?gas.?These projects are popular because they control energy costs and?reduce greenhouse gas emissions. If we have methane industrial plants installed on these sites, beyond cutting CO2e emissions, we would be helping to reduce the unemployment rate.

Using methane as a substitute source of more dirty fuels - like oil, gasoline, and coal, can significantly reduce air particles and improve air quality, but also reduce?CO2?concentration in the atmosphere. We must realize that the best way to avoid methane release into the atmosphere is by using it because burning it is environmentally much better than letting methane escape into the air.

Using natural gas (methane) as an industrial or energy source can improve dramatically the air quality in major cities.

The International Gas Union presents the following charts:

? Gas-to-Power x Other Sources: Level of Pollutants?

Natural gas produces far lower amounts of?sulfur dioxide?and?nitrous oxides?than other fossil fuels. Remember those gases has not only a high toxic level but also the highest Global Warming Potential (GWP) of all.

They are also responsible for acid rain occurrence and soil acidification. So, the best message we can leave is:?Natural gas - Methane, is the energy source globally accepted as the natural way of moving to a net-zero carbon emission economy world.