A Dynamic Solution for Sustainable CO2 Regulation
There is increasing pressure for restricting CO2 emissions in the United States, coming from within and from our international allies and trading partners. However, real concerns exist as to what can be done to control CO2 emissions. Carbon free energy is critical, but wind, solar, geothermal, and nuclear all have environmental and economic issues limiting their deployment. For the foreseeable future, fossil fuels will be used to provide energy, further releasing CO2 into the atmosphere.
Even casting aside mobile source control, no one answer apparently exists to manage emissions from stationary sources. Separation of CO2 from the flue gas (mostly nitrogen) at a point source is very expensive, in terms of both capital cost and operational expense, limiting the ability of smaller industrial operations to implement separation. Once separated, the CO2 must be pressurized and piped to a source. The long term viability of CO2 piping from sources that generate water (which means any combustion source) is unknown, and the safety concerns of corroding pressurized CO2 pipelines is potentially enormous. While using the CO2 for enhanced oil and gas recovery is a well established and creates economic value, there is a very limited capacity for real sequestration of CO2 via these routes. And terrestrial sequestration, while a good near term way to reduce CO2 emissions, can only reach a steady state, and then there will be no more net “sequestration.” When other options are rapidly exhausted, deep-saline aquifer sequestration is considered our best option and even then, the long-term viability is questionable. The primary pathway for long term sequestration, namely the formation of carbonate “rocks” requires time scales of hundreds, if not thousands of years. Few people actually expect supercritical CO2 injected at pressures higher than 5,000 psi to remain entirely sequestered for such a long time, because supercritical CO2 is an excellent solvent.
"Algae offer one of many potential paths to reduce the emissions of CO2. In fact algae can sequester carbon in the longer term, through high-value bioplastics, as well as avoidance of fossil fuel use by producing fuel from carbon already in or headed to the atmosphere." Dr. Foster Agblevor
Dr. Foster Agblevor
There is urgency to the overall situation beyond implementation of actual CO2 control. Industrial and utility concerns are facing significant economic difficulties stemming from uncertainty over CO2 abatement and sequestration, resulting in the disruption of capital allocation in the energy sector. One critical example is coal-based utility electrical power generation. While coal remains our lowest cost fuel option, new coal plants, even “clean coal” plants that are virtually sequestration ready, are not going forward. One reason is that the capital markets want assurances that the plants will meet future CO2 regulations and no assurances can be given because options for sequestration are not clear. As a result, utilities are increasing opting for natural gas plants with no possibility of future CO2 control. So while natural gas plant emits less CO2 than coal, without control, they will emit significantly large quantities that will continue for years and years without abatement. Meanwhile, natural gas, which has higher value uses in the production of fertilizer and in home heating, will rise in price as demand increases, resulting in higher food, home heating and electrical prices across the board.
Algae offer one of many potential paths to reduce the emissions of CO2. In fact algae can sequester carbon in the longer term, through high-value bioplastics, as well as avoidance of fossil fuel use by producing fuel from carbon already in or headed to the atmosphere. However, there is high degree of uncertainty about algal-based CO2 mitigation. Large scale algal CO2 mitigation has not been done. As a result, questions exist about many things.