Can a Radical New Gas Turbine Be a Zero Carbon Solution?

July 11, 2018

Well, only if they can solve the problem of methane loss at every stage of the production process. But those problems are solvable, essentially with monitoring, commitment, and some chewing gum and duct tape.

Next problem is, you’ve got a whole lot of carbon, what to do with it?

I think wind and solar are moving too fast for new fossil tech to catch up, but I’ve been wrong before.


The US energy startup, Net Power, has announced that it has successfully fired up its natural-gas plant in La Porte, Texas. In the age of climate change, when reducing emissions should be our primary goal, it may sound odd to celebrate the launch of a fossil fuel-burning plant. But Net Power is unique. Its new facility is the first fossil-fuel power plant that promises to capture all its emissions effectively at zero extra cost, and on May 30 it passed a major milestone in the step towards commercializing a climate-friendly technology.

The underpinning technology, called carbon capture and storage (CCS), has existed since the 1970s. But it is only recently that climate change-mitigation models have begun integrating large-scale CCS into their plans. Even though renewable energy, such as wind and solar, are getting cheaper by the day, the world still gets 80% of its energy from fossil fuels today. And because we have been postponing the date when the world as a whole will start to cut emissions—2017 set a new recordfor global emissions—we don’t have the luxury of waiting for the energy transition to happen on its own pace if we want to avoid missing the Paris climate goals. CCS is a bridging technology to help us avoid catastrophic climate change.

Net Power’s $150-million pilot plant near Houston makes use of the Allam Cycle, named after its inventor Rodney Allam. As Quartz previously reported, here’s how it works:

In a small turbine, a combustor burns natural gas and pure oxygen—producing only carbon dioxide and water—in a chamber that’s already full of supercritical carbon dioxide at high pressure and temperature. That’s no small feat; it’s like trying to light a match while someone else is doing their best to put it out with an extinguisher. The combustion produces additional carbon dioxide, some water, and lots of heat. This hot, high-pressured mixture is then passed through a gas turbine, where the pressure turns a shaft to generate electricity.

The slightly cooled mixture exits the turbine, then is separated into parts. The necessary amount of carbon dioxide is compressed to become supercritical again and added back to the initial chamber, keeping a steady amount of the gas circulating through the system. The remaining, pure stream of CO2 can be buried underground. And the (clean) water is dumped. The heat transfer in this process is so efficient that for each unit of energy trapped in natural gas, the Allam cycle produces 0.8 units of electricity (compared to 0.6 units produced in the most advanced natural-gas power plants).

You can read more in our feature reported in September, when Net Power was in the final stretch of construction and testing. That has now concluded, albeit a few months late, and the full cycle can now be run, according to Walker Dimmig, a principal at 8Rivers, the technology firm that co-owns Net Power with energy firm Exelon Generation and engineering firm McDermott International. The plant is not yet producing power; Dimmig says that should happen later this year.


Natural gas is displacing coal, which could help fight climate change because burning it produces fewer carbon emissions. But producing and transporting natural gas releases methane, a greenhouse gas that also contributes to climate change. How big is the methane problem?

For the past five years, our research teams at Colorado State Universityhave made thousands of methane emissions measurements at more than 700 separate facilities in the production, gathering, processing, transmission and storage segments of the natural gas supply chain.

This experience has given us a unique perspective regarding the major sources of methane emissions from natural gas and the challenges the industry faces in terms of detecting and reducing, if not eliminating, them.

Our work, along with numerous other research projects, was recently folded into a new study published in the journal Science. This comprehensive snapshot suggests that methane emissions from oil and gas operations are much higher than current EPA estimates.

One way to quantify the magnitude of the methane leakage is to divide the amount of methane emitted each year by the total amount of methane pumped out of the ground each year from natural gas and oil wells. The EPA currently estimates this methane leak rate to be 1.4 percent. That is, for every cubic foot of natural gas drawn from underground reservoirs, 1.4 percent of it is lost into the atmosphere.

This study synthesized the results from a five-year series of 16 studies coordinated by environmental advocacy group Environmental Defense Fund (EDF), which involved more than 140 researchers from over 40 institutions and 50 natural gas companies.

The effort brought together scholars based at universities, think tanks and the industry itself to make the most accurate estimate possible of the total amount of methane emitted from all U.S. oil and gas operations. It integrated data from a multitude of recent studies with measurements made on the ground and from the air.

All told, based on the results of the new study, the U.S. oil and gas industry is leaking 13 million metric tons of methane each year, which means the methane leak rate is 2.3 percent. This 60 percent difference between our new estimate and the EPA’s current one can have profound climate consequences.

Methane is a highly potent greenhouse gas, with more than 80 times the climate warming impact of carbon dioxide over the first 20 years after it is released.

An earlier EDF study showed that a methane leak rate of greater than 3 percent would result in no immediate climate benefits from retiring coal-fired power plants in favor of natural gas power plants.

That means even with a 2.3 percent leakage rate, the growing share of U.S. electricity powered by natural gas is doing something to slow the pace of climate change. However, these climate benefits could be far greater.

Also, at a methane leakage rate of 2.3 percent, many other uses of natural gas besides generating electricity are conclusively detrimental for the climate. For example, EDF found that replacing the diesel used in most trucks or the gasoline consumed by most cars with natural gas would require a leakage rate of less than 1.4 percent before there would be any immediate climate benefit.

What’s more, some scientists believe that the leakage rate could be even higher than this new estimate.

Perhaps you’ve never contemplated the long journey that natural gas travels before you can ignite the burners on the gas stove in your kitchen.

But on top of the 500,000 natural gas wells operating in the U.S. today, there are 2 million miles of pipes and millions of valves, fittings, tanks, compressors and other components operating 24 hours per day, seven days a week to deliver natural gas to your home.

That natural gas that you burn when you whip up a batch of pancakes may have traveled 1,000 miles or more as it wended through this complicated network. Along the way, there were ample opportunities for some of it to leak out into the atmosphere.

Natural gas leaks can be accidental, caused by malfunctioning equipment, but a lot of natural gas is also released intentionally to perform process operations such as opening and closing valves. In addition, the tens of thousands of compressors that increase the pressure and pump the gas along through the network are powered by engines that burn natural gas and their exhaust contains some unburned natural gas.

Since the natural gas delivered to your home is 85 to 95 percent methane, natural gas leaks are predominantly methane. While methane poses the greatest threat to the climate because of its greenhouse gas potency, natural gas contains other hydrocarbons that can degrade regional air quality and are bad for human health.



10 Responses to “Can a Radical New Gas Turbine Be a Zero Carbon Solution?”

  1. dumboldguy Says:

    Sell your Solar Roadway stock and buy Net Power, folks! Another example of a bunch of “techies” seeking to get rich while really accomplishing nothing much.

    • grindupbaker Says:

      The only part of Greenman long engineering description that’s relevant to +CO2 warming is “CO2 can be buried underground”. This is good if it is buried underground and guaranteed to stay there a few thousand years, not many required. Else it’s useless.

  2. rhymeswithgoalie Says:

    If you’re into the “This American Life”-style storytelling podcasts, check out Planet Money’s episode from last month on The World’s Biggest Battery.

    That show featured the Bath County Pumped Storage Station

  3. grindupbaker Says:

    So I ploughed through the Greenman long engineering description to find the nugget of what solid or liquid waste product of the trivially-simple exothermic reaction is to be produced instead of a triatomic gas molecule and I got “CO2 can be buried underground”. Oh whoopeedoo, how novel do you think.

  4. Sir Charles Says:

    Another pipe dream. Chewing gum and duct tape are obviously not working. Oil and gas is sector top source of US methane emissions, ahead of agriculture. Meanwhile, methane is up to 100 times worse for our climate than CO.

  5. Abel Adamski Says:

    It is all about Oil/Fossil Fuels and the petrodollar that supports the tottering edifice that is the US and by extension Global money go round (The Global Debt level is a multiple of the worlds total assets )

    The POV came up in a comment on the Guardian re the Iraq war (The Subject was the Tariffs ) – intimating the main reason for that war was not what people think, but actually because Saddam had decreed that payment for oil HAD to be in any currency EXCEPT $US.
    The $US status as the world reserve currency and trading currency is all based on the Petrodollar – which came into being when the US debt re the Vietnam War was getting obscene and the US did a deal with OPEC that meant all payments for Oil and Gas could only be in $US .
    This meant every country and corporation in the world had to hold $US and hold US Treasuries thus supporting the $US, meaning that debt levels that would bankrupt other countries are meaningless, the US can just print more money.
    Leaving the Trade issues out of it at the moment (basically what goes around comes around), there have been movements to create a New Global Currency to replace the $US which are gaining greater credibility at this time. However the Petrodollar still supports the whole US economic Ponzi Scheme and massive tax cuts.
    This is where renewables and storage slowly killing off Oil is a threat to the World financial system – or at least the US economy, especially with the tax cuts. It is a existential threat to the Petrodollar. So it is not just the fossil fuel interests who are looking after their own interests, but the whole US Financial and economic system based on unbridled capitalism and debt that is under threat. The potential with US debt with loss of reserve currency status would be Greece on super steroids.
    Why the relentless attacks on Tesla
    It is a battle for survival on so many levels

  6. Abel Adamski Says:

    Now to the Tariffs to bring manufacturing back to the US after it scurried off to China , gleefully accepting their obligatory partnership and technology transfer conditions to get access to the cheap verging on slave labor without those pesky labour or OHS requirements and to achieve the Libertarian Nirvana of no environmental or pollution regulations – Yay. Now of course the whinging starts as China is leaving them in the dust and the peasants are revolting in more ways than one.
    Note the iPhone etc is excluded from the Tariffs.

    For an explanation why, which reflects back on the Republican and Tea party and Religious Nut Job screwing up of SAmerica’s technology and industrial foundations that will take a decade or more to repair.

    Indeed, Tesla is facing some of these issues as it tries to mass-produce its Model 3s without sacrificing quality

    The consumer electronics supply chain migrated to Asia three to four decades ago and rapid procurement of components is critical to cost, time-to-market and ability to scale. Logistics and infrastructure are also key for a product that is shipped around the world — seven of the world’s ten largest ports are in China.

    Spoiler alert
    In the $30,000 to $100,000 range… and no this is not a typo

    read the article to see why

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