Carbon Capture Now
Is “reduce, reuse, recycle” enough to reverse climate change?
I wish I were Jack Johnson, sitting on a North Shore beach, watching the waves, strumming my guitar, writing songs and getting paid. “The 3 R’s” is one of my favorites. It’s about a simple and elegant solution to what is ailing our great Mother Earth — namely us. But, unfortunately, the 3R solution is not playing out as effectively as we need. Whereas recycle and reuse are slowly gaining traction — as a sheer necessity for people’s survival in some places — reduce is clearly not a favorite human inclination.
One thing we clearly are not reducing is our demand for energy. After all, we need energy for cooking and heating as well as big-screen TVs and electric vehicles, and we will keep demanding more and more of it. And while we work through the interminably slow yet epochally rapid transition to a renewables-driven world, our energy of choice remains carbon-based — specifically oil and coal.
Breaking down the carbon cycle
Carbon of course is not inherently evil; it is the core component of organic compounds, which in turn are the backbone of life on Earth: plants, animals, soil and microbes. Carbon makes up roughly 40 percent of the human body’s non-water mass and is the main component of sugars, proteins, fats and muscle tissue. We are a carbon-based life form.
Importantly, there is a natural system for recycling carbon in the world, and it is relatively simple and straightforward: animals inhale O2 and exhale CO2; plants absorb CO2 and release O2; our oceans in turn absorb and store CO2, while plankton and algae living in the oceans convert CO2 into other compounds. This system goes through various cycles in which the levels of CO2 fluctuate, but ultimately it has stayed between 180 and 280 parts per million for the past 800,000 years.
Recently, however, with the Industrial Revolution and the aggressive burning of fossil fuels, humans have been producing more CO2 than the Earth can reasonably absorb, pushing atmospheric CO2 to levels now above 400 ppm. This is a recipe for accelerated global warming, in turn correlating to melting icecaps and rising sea levels. Soon our friend Jack Johnson will need to pack up his gear and move farther up the beach to find future inspiration from a safer perch.
Can technology help solve the problem? Introducing climate tech.
So, if we are not going to reduce our demand for energy from carbon-based sources, then recapturing a meaningful proportion of CO2 emissions is vital to reestablishing balance in our atmospheric system. To that end, there are two main technology-driven pathways addressing carbon capture: point source and direct air.
Point source capture. Point source carbon capture uses filters or scrubbers on waste gases emitted from coal and natural gas power plants and other major sources of waste gas — such as iron, steel, cement, chemical and pulp plants — where CO2 can constitute anywhere from 5 to 15 percent of the volume of production-related waste gases. This CO2 can be chemically captured at emission or pre-emission, where it is separated and concentrated for use in its pure form (e.g., injected into wells for enhanced oil recovery) or in a combined form (e.g., low-carbon fuels, bioplastics, steel, concrete, coatings and carbonates like baking soda). The CO2 can also be permanently sequestered underground in repurposed oil and geothermal wells or in sedimentary rock.
Inventys is example of a company developing point source capture technologies; it uses a rapid-cycle thermal swing and a solid adsorbent to efficiently separate CO2 from flue gases. ION Engineering uses liquid solvent absorbents and 3D-printed gas/liquid contact technology to similarly capture CO2 from flue gases. Global Thermostat uniquely uses amine-based chemical sorbents bonded to porous, honeycomb ceramic monoliths to absorb CO2 from manufacturing process emissions.
Direct air capture. Direct air carbon capture, by contrast, pulls CO2 from ambient surface air, an ostensibly more difficult task as CO2 makes up only about 0.01% of surface air volume (or 100 ppm). Again, the captured gas can be sequestered in various ways, either liquefied or as a gas, and used for various industrial processes. Carbon Engineering is a clean energy company aiming to build giant ambient air–filtering facilities to capture up to 1 million tons of CO2 annually — each! One plant would offset the emissions of approximately 250,000 cars.
Climeworks is another ambient air–filtering technology company, which already has two operating direct air capture facilities. The Olivine Foundation is focusing on capturing CO2 using mineral processes it calls “SmartStones.” Olivine, a class of abundant silicate minerals, binds naturally to CO2. Through the natural weathering process and when dispersed effectively, 1 ton of crushed olivine can capture and permanently sequester up to 1.25 tons of CO2.
What does the future hold?
Many great minds are working hard on carbon capture. In addition to startups, groundbreaking innovations are coming out of academia; with the right amount of support, these initiatives will turn into fully fledged companies. The urgency of these efforts is clear and the challenges remain great. In 2007, the Virgin Earth Challenge with a prize fund of $25 million was launched in search of a technology that can unequivocally deliver scalable and sustainable greenhouse gas removal. Eleven finalists were announced in 2011, including several of the aforementioned companies. And while many are getting closer to the goal, none has yet been able to claim the prize. I am confident that one will do so soon.
At Silicon Valley Bank, our Energy & Resource Innovation team is dedicated to working with companies that are finding solutions to a number of problems across a wide spectrum of industries in the cleantech and energy technology fields. If your company is working to solve these issues or you just have an interest, I would love to connect.
