What is sustainable aviation fuel and e-fuel and how sustainable are they? My conversation with AI.

What is sustainable fuel, and how can you say it is sustainable while carrying the same Carbon backbone? Sustainable fuels are a class of fuels designed to significantly reduce net greenhouse gas emissions compared to traditional fossil fuels. While they may still have a "carbon backbone" (meaning they contain carbon and release CO2 when combusted), their sustainability lies in the carbon cycle and the source of the carbon. Here's how it works: What is a Sustainable Fuel? Sustainable fuels are broadly categorized into two main types, both of which avoid extracting new fossil carbon from underground: 1. Biofuels: These are derived from biomass, which is organic matter from plants or animals. o Examples: Sustainable Aviation Fuel (SAF) made from used cooking oil, agricultural waste, forestry residues, or algae; biodiesel from vegetable oils or animal fats; ethanol from corn or sugarcane. o Sustainability Mechanism: The key idea is that the carbon released when these fuels are burned was recently absorbed from the atmosphere by the plants during their growth through photosynthesis. This creates a closed-loop or biogenic carbon cycle. While CO2 is released, it's considered to be re-releasing carbon that was already part of the active carbon cycle, rather than adding "new" carbon from fossil reserves that have been sequestered for millions of years. 2. E-fuels (Electrofuels / Power-to-Liquids - PtL): These are synthetic fuels produced using renewable electricity, water, and captured carbon dioxide. o Examples: E-kerosene (a type of SAF), e-diesel, e-methanol, e-ammonia. o Sustainability Mechanism:  Renewable Energy: The electricity used for production (e.g., for electrolysis to produce hydrogen from water) must come from renewable sources like solar, wind, or hydropower.  Captured Carbon: The carbon dioxide used as a feedstock is either captured directly from the atmosphere (Direct Air Capture - DAC) or from biogenic sources (e.g., from industrial processes that already release CO2 from biomass). By removing CO2 from the atmosphere to create the fuel and then re-releasing it when the fuel is burned, it aims to achieve a circular carbon economy where no net new carbon is added to the atmosphere. How can it be sustainable while maintaining the same carbon footprint? The crucial distinction lies in the origin of the carbon and the overall lifecycle emissions: • Fossil Fuels: Extracting and burning fossil fuels (coal, oil, natural gas) introduces geological carbon that has been stored underground for millions of years into the active atmospheric carbon cycle. This represents a net increase in CO2 in the atmosphere, contributing to global warming. • Sustainable Fuels (Biofuels & E-fuels): o Biofuels: The carbon in biofuels originates from the atmosphere (captured by plants). When the fuel is burned, this carbon returns to the atmosphere, and then new plants can absorb it again. If managed sustainably (e.g., avoiding deforestation, not competing with food crops, minimizing the impacts of land-use change), the net carbon emissions over the fuel's lifecycle can be significantly reduced or near neutral. o E-fuels: The carbon in e-fuels is actively captured from the atmosphere or from biogenic sources (which themselves are part of the biogenic cycle). When the e-fuel is burned, that same captured carbon is released back into the atmosphere. The key is that the total amount of carbon in the atmosphere doesn't increase due to the combustion, because the carbon was already taken out of the atmosphere (or prevented from being released from a biogenic source) to make the fuel in the first place. Important Considerations and Debates: While the concept aims for sustainability, the "net-zero" or "carbon-neutral" claim for sustainable fuels often relies on a lifecycle assessment (LCA). This means considering all emissions from feedstock production (e.g., fertilizer for crops, energy for capturing CO2), processing, transport, and combustion. • Land Use Change (for Biofuels): A significant debate surrounding biofuels centers on the impact of land use change. Suppose forests are cleared or land used for food production is converted to grow biofuel crops. In that case, it can lead to significant "carbon debt" (emissions from deforestation) and other environmental issues, potentially negating the sustainability benefits. • Energy Intensity (for E-fuels): Producing e-fuels is very energy-intensive. Their sustainability hinges entirely on using genuinely renewable electricity throughout the entire production chain. If fossil fuels are used to generate electricity, the carbon savings are diminished or lost. • Availability of Feedstocks: The scale-up of sustainable fuels faces challenges regarding the availability of sustainable feedstocks (e.g., waste materials, renewable energy for e-fuels). In essence, while sustainable fuels still involve carbon and produce CO2 when burned, their sustainability is based on the principle of a circular carbon economy where the carbon is repeatedly cycled between the atmosphere and the fuel, or on using carbon that was recently removed from the atmosphere, rather than adding new carbon from ancient fossil reserves. Sources The fundamental chemistry of Carbon and its contribution towards GHG and global warming remains the same, irrespective of the origin of Carbon, whether it is biological or synthetic. You are correct in that fundamental chemical principle: the chemical properties of a CO2 molecule, and thus its ability to absorb infrared radiation and contribute to the greenhouse effect, remain the same regardless of whether the carbon atom within it originated from a fossil fuel, a plant, or was captured directly from the atmosphere. CO2 is CO2. Its molecular structure and interaction with radiation don't change based on its history. The crucial distinction, as highlighted in the previous explanation about sustainable fuels, lies in the carbon cycle and the net impact on atmospheric CO2 concentrations over time. Here's why the origin does matter in the context of climate change: • Fossil Carbon: o Fossil fuels (coal, oil, natural gas) are formed from ancient organic matter that was sequestered underground over millions of years. This carbon was effectively removed from the active, fast carbon cycle for geological timescales. o When we extract and burn these fossil fuels, we are introducing new carbon into the active atmospheric system that has not been part of that system for a very long time. This is a net addition of CO2 to the atmosphere. o The natural carbon sinks (oceans, land) cannot absorb this massive, rapid influx of "old" carbon fast enough, leading to a continuous increase in atmospheric CO2 concentrations, which drives global warming. • Biogenic Carbon (from Biofuels): o Biogenic carbon originates from living organisms (plants, algae, etc.) that absorb CO2 from the atmosphere through photosynthesis as they grow. This carbon is part of the "fast" carbon cycle, meaning it cycles relatively quickly between the atmosphere, biosphere, and oceans. o When a biofuel derived from recently grown biomass is burned, it releases CO2 back into the atmosphere. However, the theoretical premise is that this CO2 was just recently taken out of the atmosphere by the growing plants. o Suppose the biomass is harvested and regrown sustainably (e.g., replanting forests, using agricultural waste, avoiding land-use change that releases more carbon). In that case, the net addition of carbon to the atmosphere over the lifecycle of the fuel can be significantly reduced or theoretically close to zero. It's a continuous cycling of existing atmospheric carbon, rather than adding new carbon from underground. • Captured Carbon (for E-fuels): o For e-fuels, the carbon feedstock is actively captured from the atmosphere (Direct Air Capture) or from biogenic sources, such as a bioethanol plant's CO2 emissions. o This means the carbon used to make the fuel was either directly removed from the atmosphere or was already part of the biogenic cycle. o When the e-fuel is burned, it releases this captured carbon back into the atmosphere. Again, the idea is that you're not adding new carbon to the atmosphere from geological reserves, but rather circulating carbon that was already there or prevented from being released from a biogenic source. The overall carbon footprint depends on the energy source for the capture and conversion process (must be renewable). In essence: You are right that a CO2 molecule from burning coal behaves identically in the atmosphere to a CO2 molecule from burning corn ethanol or an e-fuel. The chemical identity of CO2 and its greenhouse gas properties are invariant. However, the climate impact differentiates because of the source of that carbon and whether its release represents a net addition to the active carbon cycle that the Earth's natural systems can't rapidly reabsorb. Burning fossil fuels is like continuously pumping new water into a bathtub that already has a blockage; burning sustainable fuels (when done correctly) is more like recycling the water that's already in the tub. Sources In fact, water vapour is a potent greenhouse gas (GHG), and its role is much more intensive than that of CO2. When acting in conjunction with CO2, the combination of CO2 and H2O is particularly deadly. You are absolutely right. Water vapor (H2O) is indeed the most abundant and potent greenhouse gas in Earth's atmosphere, and its role in trapping heat is more significant than that of CO2 on a molecule-for-molecule basis. When acting together, the combination of CO2 and H2O is indeed potent in influencing Earth's temperature. However, the critical distinction that climate scientists emphasize is the difference in how CO2 and water vapor behave in the atmosphere and their roles as drivers versus feedbacks in the climate system. Here's a breakdown: 1. Water Vapor as a GHG: o Water vapor accounts for the most significant portion of Earth's natural greenhouse effect, contributing to roughly 60-70% of the warming that keeps our planet habitable. o It absorbs and re-emits infrared radiation very effectively across a wide range of wavelengths. o Its concentration in the atmosphere varies significantly with temperature, location, and time. Warm, humid regions have much more water vapor than cold, dry regions. 2. CO2 as the "Control Knob" or "Forcing" Gas: o While less abundant than water vapor, CO2 is the primary long-lived, non-condensing greenhouse gas. This is a crucial difference. o Unlike water vapor, CO2 does not condense out of the atmosphere at normal Earth temperatures. It has a significantly longer atmospheric lifetime, ranging from hundreds to thousands of years. o Because its concentration is not directly dependent on temperature in the way water vapor is, CO2 acts as a primary control or forcing on Earth's temperature. Changes in CO2 levels directly lead to changes in global temperature. 3. The Water Vapor Feedback Loop (The "Deadly" Combination): o This is where the "deadly" combination comes into play, as you mentioned. Water vapor is a positive feedback in the climate system. o How it works: 1. When CO2 (or other long-lived greenhouse gases like methane) is added to the atmosphere, it traps more heat, causing the Earth's average temperature to rise. 2. Warmer air can hold more moisture (water vapor). This is a fundamental physical law. 3. As the air warms due to increased CO2, more water evaporates from oceans, lakes, and land, increasing the amount of water vapor in the atmosphere. 4. This increased water vapor, being a potent greenhouse gas itself, traps even more heat. 5. This further warming leads to even more evaporation and more water vapor, creating a self-reinforcing cycle. o Scientists estimate that this water vapor feedback roughly doubles the amount of warming that would occur from CO2 alone. So, a 1°C warming from CO2 could become a 2°C warming once the water vapor feedback is accounted for. Why CO2 is the Primary Concern for Human-Caused Climate Change: • Humans directly control CO2 emissions: We release vast amounts of CO2 from burning fossil fuels and deforestation. We do not directly control the global atmospheric concentration of water vapor in a way that would alter the climate. Any water vapor we emit (e.g., from power plant cooling towers, combustion) is tiny compared to natural evaporation and cycles out of the atmosphere very quickly through precipitation. • CO2 sets the baseline temperature; it acts like a thermostat. It determines the base temperature, which then dictates how much water vapor the atmosphere can hold. If you were to remove all CO2 from the atmosphere, the Earth would cool significantly, leading to a massive reduction in atmospheric water vapor and potentially plunging the planet into an ice age. • Long Atmospheric Lifetime: CO2 persists in the atmosphere for centuries to millennia, leading to long-term warming. Water vapor, by contrast, cycles in and out of the atmosphere in days. So, while water vapor is quantitatively the most potent greenhouse gas, CO2 is the primary driver of current anthropogenic climate change because its increase initiates and sustains the warming, which is then powerfully amplified by the water vapor feedback loop. This combination creates the significant and concerning warming trend we observe.

WHY CRT?

Why CRT (Carbon Recycling Technology)? 1. CRT is the only technology that generates a baseload (24 x 7) power, without using any fossil fuel or battery storage, and without emissions. 2. It not only eliminates Carbon emission but also replenish the depleted Oxygen in the atmosphere, which is vital for human survival. Oxygen is a valuable by-product for medical and industrial applications which adds, economic value for the project. 3. CRT is the only technology that will accelerate emissions reduction, to limit the global temperature within 1.5C before 2030 as projected by IEA and UN. 4. How can Carbon emission be eliminated while continuing to use fossil fuel and subsidising fossil fuel? 5. If CO2 is allowed, carbon capture technologies will thrive but will not solve the core issue of climate change unless the captured Carbon is eliminated from the system. 6. How future energy demands be met without baseload power generation (24 x 7) technology? Power intensive industries, electrical vehicles, and Hydrogen cars (Fuel cell) all require only electricity. Our focus should be on baseload (24 x7) electricity generation without fossil fuel but with zero emissions. Even water vapour and Oxides of Nitrogen are GHGs and to be eliminated. 7. Only a renewable fuel such as RSMG (renewable synthetic methane gas) with zero emission can save baseload electricity generation and only CRT can solve the electricity generation problem without using a fossil fuel and with zero emissions. 8. Renewable energy sources are low efficient, requires vast land and huge investment with the lowest rate of return on investment. The power tariffs are slashed, export to the grid increased but power tariffs in energy exchanges are still high. A sudden massive inflow of renewable energy into an age old grid will overwhelm the grid. It is a disadvantage for both renewable power generators well as large and continuous power users. But they are valuable and inevitable in this transition of decarbonisation 9. Renewable energy by itself will not solve electrical demand of the future. 10. Similarly, Hydrogen (whether green or blue) alone cannot solve the electrical demand of the future. 11. CRT require large upfront investment, but the rate of returns are high and payback periods are less and markets are readily available and growing. CRT Highlights: • UNIQUE VALUE PROPOSITION : • CEWT offers a distinct advantage over conventional nuclear or other power proposals by achieving near-zero emissions and minimizing reliance on fossil fuels through our innovative Carbon Recycling Technology. • • THE ENVIRONMENTAL Leadership: • CRT is well aligned with global best practices and the growing imperative for sustainable energy solutions. This can be a significant differentiator for a large multinational company that is likely sensitive to its environmental image and long-term sustainability goals. • • Long-Term Vision: CRT is a future-proof technology that addresses immediate power needs and provides a pathway to a truly circular carbon economy within their operations. • • Addresses Climate Change Concerns: • CRT directly tackles climate change by capturing and reusing CO2 emissions, unlike traditional nuclear which, while low-carbon in operation, doesn't address the carbon lifecycle of fuel production or potential reliance on fossil fuels for other parts of the energy system. • Potential for Green Premiums/Incentives: • In some regions and markets, electricity generated from near-zero emission sources can command a premium or benefit from specific incentives. This should be a part of the Indian Electricity landscape.

The Chemistry behind CRT ( Carbon Recycling Technology)

Electricity is generated using a gas turbine by converting mechanical energy into electrical energy and it can be explained by the following chemical reaction. 1.CH4 + 2O2 => CO2 + 2 H2O _ 890 KJ / mol (exothermic reaction) generating heat of combustion with the evolution of CO2 (Carbon dioxide) and H2O (water vapour) both greenhouse gases along with oxides of Nitrogen. The above fuel methane ( CH4) is the major constituent in natural gas and O2 is supplied in the form of compressed air (O2 +N2). The above heat of combustion is the source of thermal energy. 2. IN CRT (carbon recycling technology), the above process of combustion is reversed as described by the following equation: CO2 + 2 H2O => CH4 + 2 O2 +1038 KJ/mol endothermic reaction, regenerating CH4 (methane gas) and pure O2 (Oxygen). The energy required for the second reaction is more than the first reaction, which can only be supplied by an external source. In CRT this energy comes from renewable energy sources. CO2 emitted by reaction 1 is captured and stored under pressure. The water vapour (H2O) is split into H2 (Hydrogen) and O2 (Oxygen) using an electrolyser using renewable energy such as PV solar and wind. Both Hydrogen (H2) as well as Oxygen (O2) are stored under pressure separately. Oxygen is a valuable by-product. In CRT we use desalinated seawater as the main source of water for electrolysis as well as for CO2 capture and recovery. Since we use Hydrogen (H2) as a reducing agent to convert CO2 into methane (CH4) the following reaction is applicable. CO2 + 4 H2=> CH4 + 2 H2O (endothermic reaction). It regenerates both CH4 as well as H2O used above thus completing the cycle as a circular economy. The entire process of CRT uses Renewable energy in the form of renewable Hydrogen (RH). It uses only sun, wind, and seawater all natural resources available in abundance. The economics and profitability : The major investment will be in renewable energy sources such as PV solar, Wind, Hydro, Geothermal etc. Therefore, CRT can be easily integrated with existing solar farms and Hydrogen hubs. Since CRT uses desalinated water as the main source of water the plant will be located invariably on the seashore. 1. Oxygen (Hospital grade) is a valuable by-product as a major source of revenue catering to a wide range of markets and exports in the form of liquid Oxygen as well as compressed Oxygen. 2. Since CRT uses LNG only as a start-up fuel as a source of Carbon, there will be no external fossil fuel requirement for the entire life cycle of the plant for 30 years. The fuel savings will be of enormous value. 3. CRT convert CO2 emissions from the gas turbine internally into RSMG (renewable synthetic methane gas) there will be zero emissions of GHG (greenhouse gas emissions) thus eligible for Carbon credit. It is also a major source of revenue. 4. CRT is a baseload power generation plant selling power 24 x7 generating large sales revenue. All the above four sources of income make CRT the most attractive technology with high rates of return on investment and a short payback period, often less than 2-3 years even for a few billion dollars of investment. Only renewable energy projects such as solar and wind irrespective of their sizes (maybe several GW capacities) will not be able to meet the growing electricity demand in the future. It requires storage batteries thus increasing the investment substantially. Only Hydrogen generating projects irrespective of their sizes will not be able to meet the growing electricity demand in the future. Moreover, such large-scale projects require massive investment upfront with a long repayment period making it unattractive for private investments. CRT will be the only technology that can comprehensively and holistically address all the above issues in the future.

CARBON RECYCLING TECHNOLOGY

( A zero emission and zero fuel baseload power technology)" "The entire plant will run on Solar and Wind only." "Pitch for CRT (Carbon Recycling Technology) Headlining the Pitch: • CRT is a revolutionary closed-loop system that captures carbon, converts it into fuel, and uses that fuel to continuously power itself, all while generating no emissions fulfilling all the requirements of a “circular economy”. • CRT addresses two major challenges facing baseload power plants: fossil fuel dependence and carbon emissions. CRT eliminates both these concerns simultaneously. Key selling points: • Fossil fuel freedom: CRT offers complete freedom from fossil fuel after start- up, offering enormous cost savings and environmental benefits. CRT is a ""self-sustaining"" and ""perpetual fuel generation"" technology with Zero emissions advantage: With zero emission emissions, including compliance" "with regulations, and eligibility for carbon credits, CRT is setting a standard for ESG compliance in power industries. • CRT offers enormous cost savings from eliminated fuel purchases and potential carbon credit revenue. Countries like India which are fully dependent on imported fossil fuels can save substantial foreign exchange outflow. CRT can be scaled up to large capacities and set up in various locations of the country enabling emission targets to be met as a signatory of the Kyoto protocol. India can lead the world on zero emission power technology using advanced gas turbine technologies as the world is preparing for Electrical vehicles and Hydrogen (Fuel cell) vehicles, • Technology leadership: CRT offers the unique advantages of using alkaline water scrubbing of CO2 and membrane contactor degasification/stripping compared to other technologies. The capacity of the baseload combined cycle power plant: 370 Mw Electrical efficiency: 56 % Fuel consumption: 2254 mmBtu/hr Cost of natural gas: $11/mmBtu Power tariff: $ 0.15/kWh Annual fuel cost : $ 24,974/hr x 8760 hrs/yr = $ 217.20 mil Plant cost: $ 15.00 billion. Total project cost: $ 16 billion. First-year operation: 1. Power sales revenue: $ 486 mil/yr. 2. Oxygen sales: $ 8-10 billion/yr. 3. Carbon credit: $130 mil/yr 4. Fuel savings: $ 217.20 mil/yr." "Total revenue : $ 8-9 billion/yr "The life of the plnts 25 years. Since there will be no fuel usage after start-up (only initially natural gas is used as the fuel). For subsequent runs, the plant generates its fuel and power itself with zero emissions. The cost of production for power will be $447/yr. assuming SNG price @$11/mmBtu for 25 years for the life of the plant. The sales revenue will be $ 8 billion/yr. Gross profit/yr. will be:$ 7 billion ROI will be: Less than 2-3 years depending upon Oxygen price. The rate of return will be nearly about 80-85 % The power tariff is fixed at $ 0.15/kwh for the life of the plant of 25 years. With the incremental increase in tariff @ 5% the sales revenue and profitability will sharply increase!

CARBON RECYCLING PROCESS TECHNOLOGY Carbon Recycling Technology (CRT) is a process technology that uses the thermodynamic law of conservation of mass, which states that ‘ matter is neither created nor destroyed’. The Carbon atom in a fossil fuel such as coal, oil and gas remains constant irrespective of various transformations it undergoes such as combustion, reformation, gasification etc. In CRT the Carbon atom on combustion with oxidant such as air or pure Oxygen generates thermal energy emitting CO2 gas. The CO2 can be converted into CH4 (SNG) by methanation. Using renewable Hydrogen. Renewable Hydrogen can be derived from desalinated seawater by electrolysis using renewable energy sources such as solar and wind etc. However, the Carbon atom remains the same in the form of CH4 (SNG). The SNG can be subject to combustion in a gas turbine to generate power emitting CO2 once again. The CO2 can be captured and used as described above thereby continuing the cycle of power generation with zero emission into the atmosphere. The above process technology is known as Carbon capture and reuse (CCU). In our CRT process, the CO2 emission is absorbed in an alkalised seawater using a contact membrane generating Sodium carbonate (Na2CO3) solution. The resulting Na2CO3 solution is further acidified with sulfuric acid using the contact membrane similar to the above and degasified to recover CO2 in the gaseous form, which is compressed and stored for further use. The stored CO2 under pressure is further methanated using renewable Hydrogen as described above in an adiabatic reactor using proprietary catalysts. It is a highly exothermic reaction releasing large amounts of heat, which is removed using the appropriate mechanism to complete the reaction. The waste heat is used to generate superheated steam by evaporating the water which is a by-product of the methanation reaction which can be used for further use. The resulting SNG is dehydrated and stored under pressure which has a higher heating value (HHV) of 53 MJ/kg for further combustion in the above gas turbine. The CO2 emitted from the gas turbine is captured as described above completing the cycle. The above-described process is known as CRT. In normal power generation using gas turbines a readily available fossil fuel is used to generate power emitting CO2 into the atmosphere. In CRT the fuel SNG is generated internally using CO2 emission from a gas turbine. It is a power generation technology with a ZERO CO2 EMISSION AND ZERO EXTERNAL FOSSIL FUEL REQUIREMENT. By replicating CRT in various parts of the world, the CO2 along with H2O emissions can be eliminated while no fresh fossil fuel will be burnt, fulfilling the world’s abatement requirements. The initial investment for CRT will be much higher than a normal power plant with emissions but when considering the Carbon credit available and no fossil fuel will be further required and burnt the initial capital can be easily recovered in a shorter period justifying the high initial cost." "For example, a simple gas turbine with a power generation capacity of 1.20 MW emits about 960 kgs/hr of CO2 constituting less than 7% of the emission by volume at 510C. The waste heat is utilized to generate steam for internal use in the CRT process. What are the process steps involved? 1. It involves the generation of Syngas with an H2:CO ratio at 3:1 using a steam methane reformer. IT will use regasified LNG to start with. It is a well- established technology. 2. Hydrogen generation using desalinated sea water using PEM electrolysis. The process will generate sufficient Hydrogen with Oxygen as a by-product. Oxygen can be a valuable product for hospitals and industrial applications. It is a well-established technology. 3. Seawater desalination using the SWRO process with an alkalised feed for further recovery of CO2 from gas turbine exhaust to generate electricity. The waste heat will be utilized for steam generation using desalinated seawater (DM water). It is a well-established technology. 4. The CO2 emitted from gas turbines is absorbed using the above SWRO permeate which is alkaline in nature forming a solution of Sodium carbonate which will be further acidified using commercial-grade H2SO4 to release CO2 from a Sodium carbonate solution and degasified using a contact membrane. The recovered CO2 is compressed and stored for further use. 5. The above Syngas along with Hydrogen and captured CO2 will be methanated in multiple tubular reactors using proprietary catalysts adiabatically, generating renewable synthetic methane gas (RSMG) along with superheated steam as a by-product. It is a commercially established technology. The methane gas pipeline is rated with LHV at 50 MJ/kg and free from sulphur compounds. 6. The renewable synthetic methane gas (RSMG) thus generated will be recycled to the gas turbine for further power generation eliminating fresh LNG requirements. 7. Since CO2 emission is captured and converted into RSMG and recycled internally there will be zero emissions. The above-described CRT process will be a ‘Zero emission baseload power plant and zero fossil fuel usage’."

How desalination plants contribute to global warming and solutions to address them?

How desalination plants contribute to global warming and solutions to address them? I posted the following article in my blog www.clean-energy-water-tech.com in 2014. We are now addressing this problem by setting one the largest integrated membrane-based sea water desalination plants in India using renewable power without using oil and gas. Highly contaminated and concentrated effluent discharge from existing and operating desalination plants around the world have greatly contributed to global warming according to world’s leading research institutions in marine science and oceanography. https://www.clean-energy-water-tech.com/2014/02/desalination-plants-contribute-to.html The ocean’s circulation which acts as conveyor belt distributes the increasing salinity and temperature of the sea across the globe. Several companies are researching on solutions to address the above problem and to achieve a Zero Liquid Discharge (ZLD) concept. Concepts such as FO (forward osmosis), OARO (osmosis assisted RO), NF pre-treatment with EDR, recovery of minerals such as Potassium chloride, Magnesium chloride (a precursor for extraction of Magnesium metal), Lithium chloride, Bromine etc. Theoretically all these solutions are encouraging but when to come to practise there are several hurdles to get over. Currently the most popular SWRO process is to recover 40% fresh water from seawater and discharge the balance 60% with twice its salinity and contaminated chemical are discharged in the sea. Such practice is going on since sixties when RO membranes were introduced. SWRO is an energy intensive process along with thermal evaporation they contribute to a great amount of green house gases. Despite several improvements in energy conservation in membrane processes the emissions of GHG was never addressed till date. Meanwhile several large-scale desalination plants are planned and implemented to overcome severe shortage of fresh water especially in African countries and pacific island and many arid regions of the world. We in CEWT are introducing CAPZ (clean water at affordable price with zero discharge) desalination a proprietary technology that not only achieve the highest recovery of fresh water from sea water but also generates simultaneously a highly value added ultrapure saturated Sodium chloride brine that serves as feed stock for chloralkaline industries substituting ‘solar evaporated salt’ as a source of Sodium. The pure saturated Sodium chloride brine is the feedstock to produce Caustic soda using membrane electrolysis as well as to produce Soda ash using Solvay process. Modern chloralkaline plants are very large in scales of operation which requires large quantities of solar salts. Due to climate change and unseasonal monsoon rains that have severely affected the solar salt production world-wide leaving a large gap between demand and supply. It has sharply increased the price of solar salt in the international market. Bulk of the solar salt is also used in ‘de-icing’ road due to severe snow in the industrialised countries. CAPZ desalination can recover up to 72% fresh water as well as 4.70% saturated sodium chloride brine simultaneously. Directly from seawater. Our current proposed plant in India will produce about 10,000 Mt of saturated Sodium chloride brine per day or 3150 Mt/day of high-quality salt along with 80,000 m3/day of fresh water from a seawater intake of 182,000 m3/day achieving zero liquid discharge (ZLD). We can also retrofit OARO system in our process to further increase water and salt production making it the most effective and economical and environmentally desalination technology in the world!