End-User Carbon Capture

by Shane Sweet

“Carbon” is a word we hear plenty.  Back in the day when I first got into the industry, carbon dioxide as a contributing factor to climate change was a topic reserved for the scientific community.  In fact, the term global warming was not even used until the mid 1970s, or so I’ve read.  At the time, street-level discussion re carbon was limited to debate over which oil burner created the most of it (read: soot); or whether the quality of a competitor’s diesel was inversely proportional to the amount of black smoke from a diesel engine.

The USEPA says carbon dioxide is the primary greenhouse gas emitted through human activities and in 2013, accounted for about 82% of all U.S. greenhouse gas emissions from human activities.  Although fuel combustion by-products generally list carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides, lead and particulate matter, carbon gets painted as the bad boy, (depending upon where it is, of course).

If carbon is bad, then in practical terms, carbon is near or at the top of the list of problems energy folks have to contend with today.  From a legislative, regulatory or political perspective, it’s rare nowadays to hear the words ‘fuel’ or ‘energy’ without ‘carbon’ in the same breath.

For power generation folks, carbon is a problem.  Electricity in the United States for homes, business, and industry accounts represents the largest single source of CO2 emissions; accounting for about 37% of total U.S. CO2 emissions, and 31% of total U.S. greenhouse gas emissions in 2013.

For those fueling the transportation sector, carbon is a problem too. Transportation use of gasoline and diesel equates to the second largest source of U.S. CO2 emissions, weighing in at about 31% of total U.S. CO2 emissions and 26% of total U.S. greenhouse gas emissions in 2013.

For those in the business of fueling industrial process, emission of CO2 via fossil fuel combustion is, again, a problem.  Fossil fuel combustion from various industrial processes accounted for about 15% of total U.S. CO2 emissions and 12% of total U.S. greenhouse gas emissions in 2013.

With all this carbon floating around, so called carbon capture and storage (a.k.a “CCS”) is considered a plausible way to dramatically reduce carbon emissions in an affordable way.  Given that you cannot store what you cannot capture it first, let’s stick to capture for now.

Capture means carbon (dioxide) is removed, or separated from, the entire power, heat or industrial process equation. Note that capture of carbon via CO2 is considered a much easier and practical method for getting your hands on carbon.  Three solutions can capture 90% of carbon dioxide emissions at commercial scale:

Pre-combustion: “Pre” capture entails coal or gas pre-treated and converted into a mix of hydrogen and carbon dioxide.

“Oxy-fuel” combustion: “Oxy” systems burn coal or gas in oxygen instead of air.  The result is a more concentrated carbon dioxide providing for easier separation.

So called post-combustion capture: “Post” captures CO2 from the exhaust by absorbing it in a solvent and the absorbed carbon dioxide is then removed from the solvent.

So, the good news is that the technology exists for capture; the bad news is that there were but a dozen commercial-scale CCS projects in operation as of a couple years ago, and that was worldwide.

All we need now is an end-user level carbon capture device.  This magic “black box” will be:

• Scrubbing CO2 from combustion gases anytime fuel is being burned
• Integrated with a user-exchangeable carbon (dioxide) storage canister
• Small; perhaps no more than a cubic foot in volume
• Installed in the basement, in the field, or inline on the exhaust/vent pipe
• Easy to install
• Inexpensive
• Reliable; perhaps few or no moving parts (think chemical process, like a fuel cell)
• Run on line voltage or not, the latter runs on low voltage electricity produced by the engine or heating appliance. Great for areas where there no power is available

If we had a device that allowed us to simply, efficiently and inexpensively scrub carbon from the emissions of our furnaces, boilers, water heaters, we’d be the darling of the enviros, right?

Maybe not.

Shane Sweet is an energy and management consultant with clients in the heating oil, propane and motor fuel sectors, a partner with the firm of Lake Rudd & Company. Sweet is the executive director and technical director for the New York PropaneGas Association. He served the industry as president and CEO of the New England Fuel Institute from 2007 to 2011, and as executive vice resident/director and lobbyist for the Vermont Fuel Dealers Association from 1993 to 2007. Sweet lives in Shaftsbury, Vt., and may be reached at shanemsweet@gmail.com or 802-558-6101 cell/text.