User:Lorenzorosa92/sandbox

Look at Meghna's Sanbox for CCS Projects Article: https://en.wikipedia.org/wiki/User:Meghnar11/sandbox

Lorenzorosa92 (talk) 16:35, 3 May 2017 (UTC)Make up extra credit

Water-energy nexus

Water may limit energy production both from renewable sources and through the extraction of fossil fuels. Water availability is a major factor constraining the ability to meet energy production by the growing human population. The rising importance of the water-energy Nexus has been recognized by International Energy Agency in two special sections in the World Energy Outlook in year 2012 and 2016. Moreover, the impact of climate change on the hydrological cycle is an increasing concern in the energy sector, where more than three quarters of the world top energy companies indicate that water is a risk for their business operations .

While so far most of the energy demand after the industrial revolution has been met with conventional fossil fuels that require relatively low water costs for their extraction  − in addition to renewable energy such as hydropower that has a water consumption to offset evaporative losses in reservoirs − the near future will see an increasing reliance on unconventional fossil fuel deposits − such as oil sands, shale oil and shale gas − that require greater amounts of water.

New energy technologies implemented to decarbonize our economy are increasing our reliance on water-intensive fuels further exacerbating the interconnection between energy and water. Bioenergy policies (US Congress, 2007; EU Parliament, 2009) have mandated a certain degree of reliance on renewable energy, stimulating the development of the biofuel industry with a direct competition between food and energy uses of crops and embodied water. Solar power production needs water to clean panels from dust deposition. Actual technology implemented to capture and store CO2 relies on large amounts of water.

Carbon Capture and Storage (CCS)
Carbon capture and storage (CCS) is a promising technology to holding-back climate change while reducing CO2 emission from fossil fuel.

Post-combustion carbon capture
Coal and natural fired power plants, refineries, steel, cement and fertilizers production plants can be retrofitted with a carbon capture unit. Actual post-combustion carbon capture technology is based on absorption capture units, which rely on large volume of water to separate CO2 from the flue gas. Carbon dioxide is absorbed using a solvent of monoethanolamine (MEA) in aqueous solutions. Current facilities with CCS absorption units increase water withdrawal by 25%–40% and water consumption by 50% to 90%. According to the National Renewable Energy Laboratory, a coal plant with CCS technologies requires roughly 3,785 liters (1,000 gallons) of water for every megawatt-hour of electricity generation. The increase in water usage from an absorption unit with MEA is because of a decrease in the overall energy efficiency of the plant and because it has a number of cooling sub-processes that require water.

The water requirements associated with current MEA technologies for carbon capture are attributable to solvent regeneration or stripping process. The water and energy intensity of currently available CCS technologies underscore the importance of pursuing less water-intensive and more efficient options for carbon capture technologies. Improved materials are key in developing post-combustion capture. Research is currently developing adsorption and membrane technologies that could be implemented to capture carbon dioxide reducing the water requirements of MEA absorption. However, research remains at pilot scale to prove the technical and economic feasibility of absorption CO2 capture.

Bioenergy Combined with Carbon Capture and Storage (BECCS)
BECCS involves growing biomass, burn that material to produce energy, capturing the CO2 emitted during combustion and store in underground. Despite BECCS is a viable technology, there are multiple challenges to its implementation at large scale. Land use and water consumption would create a strong competition with water and land required for food production needed for the burgeoning global population.

References