Negative Emission Technology: STEP
By Omar Lux (4/29/2019)
What is becoming increasingly obvious is the fact that negative emission technologies (NETs) must complement emission reductions and natural carbon sink enhancement, if the planet is to become restored. I want to bring your attention to one particular scientifically peer-reviewed Negative Emission Technology (NET) called Solar Thermal Electrochemical Process (STEP). It is a highly efficient and scalable technology designed to remove carbon dioxide (CO2) directly out of the air. It stands out as perhaps being the most viable NET option for the following reason:
1) Scaling it up will not result in a loss of efficiency; STEP’s creator, Dr. Stuart Licht, calculates that a fully scaled operation is capable of reducing today’s CO2 concentration to preindustrial within a decade.
Powered by renewable energy, the STEP concept takes place in an electrochemical reactor, where a vat is filled with lithium carbonate (LI2CO3), along with two electrodes submerged in it. Electricity is passed through the electrodes, which results in one electrode splitting the Li2CO3 into carbon (C) and lithium oxide (Li2O) and the other releasing oxygen (O2). CO2 in the surrounding air is attracted to the Li2O and combines to form Li2CO3 again, resulting in a constant supply of Li2CO3 and therefore a continuous process. STEP never requires CO2 pre-concentration in order to operate efficiently.
The C produced as a result of the CO2 splitting can take a few forms, the most valuable of them being carbon nanofibers (CNFs). CNFs can be made hollow, thereby becoming carbon nanotubes (CNTs). CNTs have multiple industrial applications, including the components of renewable energy devices. Thus, STEP supports its own expansion by creating a raw material needed to produce its power source. STEP offsets any CO2 associated with the production of its components.
A Manhattan Project-level of commitment, or about 130,000 participants, is required to expand STEP to a degree that will mitigate climate change. An initial $20 million is needed before the technology will likely become self-funding, assuming the value of its carbon byproducts is fully exploited.
One possible way to expedite the process of scaling STEP up is to contact the official body who established the Paris Agreement and persuaded over 100 countries to sign it. If you have any other suggestions of the most responsive groups to get a hold of, please contact me via my email attached below.
Contact info: firstname.lastname@example.org
NET:STEP Q & A
The molten electrolysis gets as hot as 770 C. The process is heated by the thermal component of the sun during the day and efficient thermal energy storage at night (such as solar power towers); that’s why areas of very high insulation (Sahara Desert, Mojave Desert, Australian Outback) are ideal for the process. The CO2 splitting efficiency is maximized by utilizing both the light energy (concentrated by heliostats & harvested by concentrator photovoltaics) and heat energy of the sun. The CPVs operate at 37% efficiency, and the added thermal component increases their efficiency even more.
It requires 7 MWh per ton CNTs. Voltage ranges from 0.8V to 2V, depending on Li2O concentration and current density
Carbon is removed from the molten solution by extracting, cooling, or uncoiling the cathode from which it originates.