• Distributed Energy Resources
  • Carbon Emissions
  • Carbon Reduction

DAC as an Inventive Approach to DER Carbon Sinks

Jessie Mehrhoff
Sep 04, 2018

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Direct air carbon capture (DAC) historically has been considered a cost-prohibitive response in efforts to mitigate rising temperatures. Despite concerns about its growing concentration in the atmosphere, CO2 makes up only about 0.04% of the mixture of atmospheric gases. Further, CO2 is distributed fairly evenly around the globe, without regions of high concentration ripe for capture. If a collective technological transformation is to keep global temperatures from rising above 1.5°C, then disruptive technologies such as DAC may have a role to play when integrated into existing DER platforms.

Increasing Carbon Sinks

Global Thermostat is one of several DAC firms advocating for carbon capture as a necessary component of the global climate solutions portfolio. A variety of existing technologies either capture carbon before it is emitted or reduce the amount generated in the first place. DAC, however, distinctively draws down already emitted CO2. Global Thermostat’s DAC plants use waste or other low cost heat to move ambient air through filters that capture CO2. Once harvested, a variety of industries including synthetic fuels, enhanced oil recovery, and biofertilizers can use the CO2.

Such a DAC system readily integrates into existing electricity generation due to its dependence on heat to capture CO2. Clean DER, such as solar PV farms, generating excess heat could integrate with DAC plants and market themselves as carbon negative.

DAC plants can be constructed just about anywhere and integrated with existing power sources. Given this fact, Global Thermostat suggests that its technology eliminates the need for transported carbon, further reducing global emissions.

Clean fuels synthesized from atmospheric CO2 can be of benefit in places where carbon capture must take place offsite. Carbon Engineering suggests that, rather than solely restructuring our current infrastructure away from mass transportation, carbon can be used to synthesize clean fuels. The company’s DAC technology boasts the ability to transform atmospheric CO2 into a fuel that is entirely substitutable for the fossil fuels powering planes, trains, and automobiles. Carbon Engineering envisions that the commercial deployment of its technology will take place by 2021, with facilities capable of generating 2,000 barrels of clean fuel each day.

Will DAC Thrive in Today’s Market?

The estimated levelized cost of DAC has dropped from $600/ton of removed CO2 in 2011 to between $94 and $232/ton today. Despite lower costs, the CO2 market may not yet be lucrative enough to encourage wide-scale capture. The current, relatively low price of CO2 will prevent the proliferation of DAC technology:

  • Low or no-cost CO2 emissions disincentivize industrial manufacturers to capture carbon onsite;
  • The unprofitable nature of carbon sequestration into the geosphere make DAC an investment primarily for industries that have a direct need for carbon;
  • Issues of scalability continue to discourage smaller DAC plant creation.

As the cost of carbon remains relatively low and the need to reduce atmospheric CO2 remains high, it might be in the interest of DAC to integrate with DER technologies. By capitalizing on low cost or free-energy provided by DER like solar at non-peak times, DAC could help to produce higher value products like synthetic fuels and take advantage of the over $1 trillion carbon market and improved US tax credits.

Reducing transportation costs while creating carbon sinks is an attractive means to further green the Energy Cloud, and visionary couplings of onsite renewable energy production and DAC technologies paint a picture of future localized, carbon negative production. By capitalizing on distributed generation to fuel carbon capture, DAC has the potential to serve as a valuable component of global energy system decarbonization.