What Is the Price of Net-Zero Emissions?


The following is an article originally published on Energy Central’s website on Dec. 14, 2021.

There’s significant talk surrounding what it’ll take to finally reach net-zero — but how much will this undoubtedly massive undertaking cost?


By Dr. Roxby Hartley, EcoEngineers


The push to assign blame for climate change to the big environmental polluters is gaining momentum.

A few sectors have been responsible for generating a large percentage of the carbon emissions responsible for climate change. The large petroleum companies are blamed for the petroleum products we use; the agricultural sector for methane; and the mining, cement, and steel industries for their share of emissions. Companies in these sectors — and their outputs — have been responsible for the construction of the modern world, and demand for their products continues to grow.

As we have learned time and time again, enforceable regulations prevent pollution. So in many ways, we can’t blame the industry for the mess we’re in. If a company were environmentally conscious in the 1960s, then it would have been outcompeted and its market consumed by those with a cheaper product. There was no cost imperative to reduce or capture emissions.

Producing change meant voting in a government that addressed emissions. Take the Low Carbon Fuel Standard program in California as an example. The regulator managing the program, the California Air Resources Board (also known as CARB), takes great pains to ensure that the program works and has integrity. It is science-based, measuring the cost of all the emissions that go into fuel. Regulations such as this one are critical to reaching net-zero.

Examining the Possibility of Sustainable Offsets

The manufacture and use of gasoline produce a lot of emissions per unit of energy. In fact, it results in emissions of around 100 grams of carbon dioxide equivalent per megajoule of energy. What does that mean? The 100 grams include all the emissions from extracting the raw material, making and distributing the fuel, and combustion of the fuel. This is called life cycle emissions.

Petroleum comes from long-dead plankton buried for eons (or more correctly, epochs!), and its combustion takes carbon from the ground and puts it into the air and the oceans as CO2. The CO2 in the air acts as a greenhouse gas, absorbing and reemitting the warm infrared radiation that the earth emits to lose heat. The CO2 in the oceans acidifies said oceans, expanding the oceanic hypoxic and anoxic dead zones in our warming world, making it more and more difficult for creatures to form shells.


How much carbon does gasoline emit? It’s quite surprising that CO2, a molecule with two oxygen atoms and one carbon atom, is more than three times heavier than the carbon itself. A gallon of gasoline has 116 megajoules worth of energy, so when it is burned (at 100 grams of CO2e per megajoule from its life cycle), it emits around 26 pounds of CO2. Burning 86 gallons of fuel releases a metric ton of CO2 into the atmosphere.

To become sustainable, all the emissions from the life cycle of gasoline must be offset. Perhaps the only industrial-scale solution is carbon capture and sequestration, or CCS. Adding CO2 into underground storage costs about $75 per ton, so roughly 81cents per gallon of gasoline combusted, and a big 30% (or so) increase in fuel cost. If we are going to reach net-zero, that’s the minimum price increase we can expect on fuel. Similar math applies to farming, but increasing the cost of food will be even less popular than rising fuel costs. For net-zero, any industries that produce emissions must capture all their greenhouse gas emissions and pay for them to be sequestered.

We haven’t thought about paying to capture the CO2 that we burn when the water for our shower is heated; our home is warmed; our food cooked; and when we travel, or fly, or pour the foundation for our buildings. However, to achieve net-zero, all greenhouse gas emissions must be sequestered — and it is a cost that we are all going to have to bear.

Calculating the Cost of Net-Zero

What will that price be? What is the incremental cost for each extra ton of CO2? Capturing CO2 from concentrated industrial sources is relatively cheap, but there is little in the form of low-hanging fruit. All the “easy” CO2 will likely be captured by the end of this decade, but there isn’t nearly enough.

Capturing carbon at low (and gradually increasing) concentrations in the atmosphere is much more expensive. If that capture costs $500 a ton, then it’s a 200% increase in the cost of gasoline and not a 30% increase. Making all industrial activity sequester its emissions or buy offsets is a surefire way to get to net-zero — but the process is going to be slow and expensive.

We can’t begin too soon. CARB has inspired that start, with CO2 priced in the markets at $200 a ton. Let’s hope other jurisdictions follow suit and enact regulations to stop our headlong destruction of planet earth.

All concentrated (“easy”) sources will follow down the CCS route. Natural gas-burning power stations (or hydrogen burning, using small modular reactors to focus a CO2 stream before combustion) will follow. After that, there is the complicated problem of transportation fuels, and there is no way to capture tailpipe emissions from a car, truck, or plane.

An increasingly vital solution to reduce greenhouse gas emissions from tailpipes is biofuels that emit recycled carbon, zero-emission electric power, and hydrogen. Sources of electricity (or EV) and hydrogen (or H2) can be concentrated, and the CO2 captured. Ethanol produces concentrated CO2 that can be sequestered, and it will be a solution where EV and H2 cannot be applied — particularly if the ethanol is converted to aviation fuel. Other technologies in the pipeline include conversion of municipal solid waste to fuel via gasification and the Fischer-Tropsch process as well as capturing methane emissions from farming. All these will lead us toward net-zero, but not without costs.

In the future, CO2 will be a commodity shifted to storage across the globe. The industry is nascent, the pipelines are being planned, and the storage geology is selected. For climate change to slow — for the steadily climbing CO2 concentrations in the atmosphere to decline — governments must choose to enact regulation, and we are going to pay to create an industry that few have yet comprehended.


Roxby Hartley headshot

Roxby Hartley, Ph.D.

Dr. Roxby Hartley is a senior regulatory consultant at EcoEngineers. He has expertise in biofuel production, carbon capture and sequestration, compliance management, sustainable program development, and the California Low Carbon Fuel Standard. For more information about low-carbon fuels, or decarbonization strategies, contact Roxby at rhartley@ecoengineers.us.