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Poll results and the discussions: A recent poll conducted in Linkedin and the results discussed as follows:

1.According to the poll recently conducted 73% of people said, “decarbonization” means to reduce Carbon emission. How to reduce CO2 emission when every time we switch our lights on or start our car engine CO2 is automatically emitted? It is possible only when the electricity we use (lights or Electric car) have zero or substantially reduced carbon footprint. Each individual house can have roof top solar panel with storage battery just for their consumption so that they can achieve zero carbon footprint. Alternatively small house holds (hundreds to thousands) can collectively install fully automated micro grids for their power generation and distribution network using solar and wind with battery storage and not to export or import from the centralized grid meant for large power generators for industrial applications. They can also have their own gas network (mixture of 80% natural gas + 20% renewable Hydrogen) for individual CHP applications. The centralized grid should have a zero emission or substantially reduced Carbon emission highlighted in the following paragraphs.

2. Zero percent people said Carbon should be substituted entirely by Hydrogen. The top 10 GHG emitting countries can use either EV or Fuel cell vehicles or a combination of these two for transport applications provided the electricity supply have a zero or substantially reduced Carbon footprint. For power and heating/cooling requirements individual houses can install their own CHP units using gas network (a mixture of 80% natural gas + 20% renewable hydrogen). Fuel cell cars can use renewable Hydrogen generated using PV solar/ wind turbine.

3. 13% of the people voted for adding Hydrogen to carbon. A distributed power system using syngas (a mixture of CO and Hydrogen) as a fuel to generate electricity and district heating and cooling using waste heat can be installed. The resulting CO2 emission along with water vapor can be captured and recycled in the form of syngas using PEM or SOFC electrolyzers.

4. 13% of the people voted for Carbon to disappear. I guess they prefer Carbon capture and use or storage (CCUS) or Carbon capture and sequester deep underground. This technology is yet to be proven commercially on large scale especially by power plants using coal. But “making carbon disappear” is impossible because it violates the fundamental law of physics (matter can neither be created or destroyed). It can be stored temporarily deep underground, but I question the technical feasibility and economic viability of such a scheme. Coal has been used for power generation due to its cheap availability and cheap cost of power generation despite a low electrical efficiency at 32%. But CO2 content in the flue gas is only around 11% and recovery of CO2, compression, long distance transportation and sequestration may substantially increase the cost of CO2 disposal making electricity very expensive. It will be simply unviable.

Top 10 GHG (greenhouse gases) emitters in the world

(Source: World resources institute)

The top three GHG emitters- China, EU and USA contribute 41.5% of the total global emissions while the bottom 100 countries account for only 3.6%. Collectively the top 10 emitters account for over two third of the global GHG emissions according to WRI.

Chart, sunburst chart

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Summary of Life cycle GHG emission intensity (Source: World nuclear association report) 

Technology  Mean  Low  High  
tones CO2e/GWh  
Lignite  1,054  790  1,372  
Coal  888  756  1,310  
Oil  733  547  935  
Natural Gas  499  362  891  
Solar PV  85  13  731  
Biomass  45  10  101  
Nuclear  29  2  130  
Hydroelectric  26  2  237  
Wind  26  6  124  

About 84% % of the world’s energy in the year 2020 was met only by fossil fuels according to Forbes based on BP’s annual review.  Therefore, CO2 emission reduction should be targeted mainly by power generation and transportation industries two major users of fossil fuels.

Various methods of using fossil fuels for power generation and their CO2 emissions are shown below assuming Oxy combustion and gasification are used.

Fuel                  Process                      Reaction               CO2 emission by wt. percentage 

  1. Coal           combustion              C + O2 => CO2           100% 
  • Coal            Gasification        2C + H2O + O2 => CO +H2 +CO2.       97.30% 
  • Natural gas  Combustion        CH4 + 2O2 => CO2 + 2H2O              52 % 
  • Diesel   Combustion     C13H28 + 20 O2 => 13 CO2 + 14 H2O.     69.4 % 

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Note: 

THE OXIDANTS USED IN ALL THE ABOVE PROCESSES ARE PURE OXYGEN AND NOT AIR

(Air oxidation will show low CO2 emission by weight percentage due to large portion of Oxides of Nitrogen, Nitrogen and excess oxygen present in the flue gas)

1.By simply closing all coal operations and switching over to natural gas for power generation the CO2 emission can be reduced by 48% compared to coal and by 17.4 % compared to Diesel.  It is critical top 10 emitters of GHG emission should close all their coal fired power plants by 2022 or impose Carbon tax at the rate of $250/Mt to force such closures. CCS or CCUS can be allowed by coal fired power plants provided such technologies are commercially proven and verifiable. Otherwise, Carbon penalty should apply retrospectively.

2 All gas fired power plants can use either natural gas or Syngas (H2 +CO mix) using Oxy combustion to generate power and achieve an electrical efficiency of at least 65% by bottom cycling with sCO2 power cycle using waste heat or 85% using CHP application. Synthetic natural gas (SNG) can substitute natural gas (fossil origin) by using DIC dissolved inorganic in the form of CO2 recovered from seawater and renewable Hydrogen so that SNG will be Carbon negative. Alternatively, CO2 recovered directly from air can be used to synthesize SNG using renewable hydrogen. Carbon pricing will encourage such Carbon negative fuels.  Fuels synthesized from captured CO2 from natural gas fired power plants and hydrogen should be treated as “Carbon neutral’ till 2022 and it should attract carbon tax beyond 2022.

3.Oxy combustion closed super critical CO2 power cycle using natural gas is to be encouraged by enabling pipeline CO2 to be recycled in the form of renewable synthetic methane gas (RSMG) using renewable Hydrogen thus achieving zero emission. It should be confined to individual location and RSMG should not be allowed to be exported but recycled within the premises.

4.CO2 emissions by transport can be reduced by 17.8% by substituting diesel vehicles with CNG by countries other than the top 10 emitters. Top emitting countries can use Fuel cell using renewable Hydrogen banning IC engine using fossil fuels or allow Electric vehicles with Fuel Cell extenders.

5. Deployment of largescale renewables such as solar and wind as well as biomass technologies substituting coal fired power plants will be the key. However renewable energy is only intermittent and will require large scale battery for energy storage. Even battery production emits 150-200 kgs of CO2 per kwh based on the energy consumption @97-181 kwh per kwh battery production (Nearly 200 times more CO2 emission than coal fired power plants). Therefore, utility scale batteries should be justified. Therefore, Bioenergy can play a major role in countries like Australia, African countries, Indonesia, India and Brazil in decarbonization especially biocrude can be converted into renewable synthetic fuels as Carbon neutral fuels.

6. Renewable energy such as solar and wind can be stored in the form of syngas by electrolysis of CO2 emissions from Oxy combustion of natural gas or by gasification of coal as shown above. Low temperature electrolysis using PEM or high temperature electrolysis using SOFC (solid oxide fuel cell) can convert CO2 into syngas. Both the processes have been already demonstrated. Syngas can be stored under pressure, and it can be used as a fuel for a continuous production electricity using Oxy combustion such as sCO2 Brayton cycle and recycling CO2 in the form of Syngas.

CO2 + H2O => H2 + CO (by electrolysis using PEM or SOFC)

7.Using Oxy combustion of natural gas in closed super critical CO2 Bryton power cycle and recycling CO2 internally in the form of RSMG using renewable Hydrogen, ZERO EMISSION base load power can be achieved. The advantage of this system it requires natural gas only for the start-up and it can generate RSMG internally using renewable Hydrogen. It can generate baseload power with zero emissions. And the electrical efficiency of such as system can be up to 65%. It runs completely using only renewable energy sources such as solar and wind. Water electrolysis using PEM or Alkaline Electrolyzer have been commercially proven.

It does not require any energy storage at all. The power can be directly exported to the centralized grid as well as imported from the grid for hydrogen generation. 

By adopting CRT (Carbon recycling technology) outlined above it is possible to achieve zero emissions by power plants and supply power to all industries including transport industries. 

By the introduction of Electric vehicles and Fuel cell vehicles replacing petrol/diesel vehicles the electricity demand will sharply increase in some countries which will proportionately increase GHG emissions. CRT can eliminate GHG emissions as shown above.

The best option is to generate base load electricity with zero GHG emissions using CRT using sCO2 power cycle and recycling CO2 in the form of RSMG and converting waste heat into electricity by bottom cycling using sCO2 power cycle thus increasing the electrical efficiency to more than 70-75%. Advanced bioenergy to convert biomass directly into biomethane can play a major role in decarbonization. It will require massive plantation of high CO2 absorbing short life plant varieties all over the world but unlikely to happen.

Implementation of the above technologies will require massive amount of water especially for renewable hydrogen and for biomass production and gasification and the major source will be the sea. Advancement in seawater desalination such as high recovery, low energy consumption, better concentrate management by recovering value added chemicals and minerals and substituting solar salt by high purity brine directly from seawater desalination will be required, achieving zero liquid discharge in SWRO plants will be critical to eliminate global warming by highly concentrated effluent discharge. All SWRO plants should use only renewable energy sources sch as solar and wind or Hydro.

The above suggestions are purely based on the author’s assessment based on his personal experience in the industry for the past 40 years.

Energy industry is at a crossroad. It must now find a new direction to address the climate issue while to continue to supply energy to the world. The options are very clear. It can find new ways and means to genuinely address some of the mistakes of the past by inventing new methods to address the problem irrespective of the cost involved because time is not in our favour. Alternatively, one can redirect the issue using new terminologies and jargons and temporarily buy some time till finding an alternative and lasting solution to the problem. The first option will take time and cost more, and the second option may not take time and cost less. It seems most of the companies are choosing the second alternative. But how?

Renewable energy is defined as “a source of energy that is available from the nature that can be constantly replenished”. This will guarantee the sustainability. But we are used to Carbon based fuels and technologies and therefore we also need a renewable Carbon that can substitute fossil fuels so that existing technologies for power and transportation can be used. Biomass is also derived from plants and animals like fossil fuels, but it is different in terms of time scale, and it can be replenished quickly unlike fossil fuels. It is basically made up of Carbon, Hydrogen and additionally oxygen, like fossil fuels such as coal, oil and gas but free from sulphur. Therefore, one can use the same technology such as combustion, gasification and pyrolysis etc and convert a biomass into energy, chemicals and fuels while claiming them as “renewables”. It will require oxy-combustion and gasification methods and unfortunately usage of pure Oxygen will be inevitable.Therefore, both Carbon as well as Hydrogen derived from biomass becomes “Green” and “renewable”. In addition “Green Hydrogen” using renewable energy sources such as solar and wind by water electrolysis will help decarbonisation by capturing and converting CO2 emissions into a Syngas. It requires a steep fall in the cost of renewable electricity to less than $20/Mwh and Carbon emission to be taxed at least @ $250/Mt to discourage fossil industry. Once we establish green and renewable Carbon and Hydrogen then it is only a matter of generating a syngas, combination of Hydrogen and Carbon monoxide with various ratios to synthesis various chemicals including bio crude oil that leads to refineries to produce petrol, diesel and aviation fuels. We will be back into the game but with different brand called “Green and renewable”; it is “an old wine in a new bottle” Everybody is happy and politicians can now heave a sigh of relief and feel comfortable. One can also use “blue hydrogen’ as a mix to green hydrogen and synthesis various downstream chemicals such as Ammonia, urea etc.

Thus they can use them to decarbonise the fossil economy. In either way there is still an issue of CARBON EMISSION that needs to be addressed. They may claim biofuel as Carbon neutral, but it will not stop the increasing concentration of GHG into the atmosphere or climate change. Therefore Carbon tax will be inevitable. Bioenergy and renewable energy may increase the sustainability but will not address the issue of global warming and climate change. Nature does not discriminate between ‘bio-carbon’ and ‘fossil carbon’. Only “Carbon Recycling Technology” can address the problem of global warming and climate change. In our process of CRT we neither use “bio-Carbon” or “fossil Carbon from coal, oil and gas but CO2 derived from DIC (dissolved inorganic Carbon) from seawater.That is why the Hydrocarbon derived in our process is called Carbon negative fuel. Moreover it recycles the CO2 emission resulting from such hydrocarbon within the sCO2 (super critical CO2) power system with Zero CO2 emission.The simplest method for transport will be to to collect CO2 emission from all petrol and diesel engines in a liquid form using a retrofittable device in the vehicle and convert them in a centralised facility to Syngas using renewable Hydrogen .The syngas can be converted into renewable crude using F-T reaction hat can be processed in a refinery for recycling into petrol, diesel and aviation fuel so that we can eliminate technologies such as large batteries and Fuel cells. By this way we can ensure the CO2 level in the atmosphere is stabilised and existing infrastructures are utilised. The availability of biomass for a radical change will be an issue especially in Asia where growing population requires more land for agriculture and deforestation is a common problem. It is absolutely clear that the same old fossil industry will promote Hydrogen in a much bigger scale so that oil and gas industry will re-brand itself as “Green and Renewable” and continue to grow along with their CO2 emissions unabated.

Australia energy mixcost of living not skrocketed by Carbon taxCHP plant CO2 reductionTaxing Carbon pollution is already paying the dividends according to the National Energy Market of Australia. Such a tax will encourage fossil fuel fired power plants to review   the way they generate power and emit the Carbon into the atmosphere. For example, black and brown coal power plants can switch over to gasification technology from their existing combustion technology  which can cut their Carbon emissions. Coal fired power plants can switch over to gas-fired power plants and cut their emissions by almost 50%. By employing CHP (combined heat and power) the gas-fired power plants can cut their Carbon emission as much as 75%. Taxing Carbon will encourage efficiency and reduce pollution. Australian Carbon tax is a good example which has clearly shown the way to cut Carbon pollution and to encourage renewable energy. The following is an excerpt from Climate Institute of Australia:

“Emissions from electricity are falling:

Annual carbon emissions from the National Electricity Market fell by over 12 million tonnes (CO2-e) between June 2012 and May 2013. They fell by only around 1.5 million tonnes over the previous twelve-month period. Carbon pollution per megawatt-hour has also fallen: from 0.86 to 0.81 tonnes per unit of output, or a little over 5 per cent.

According to the National Energy Market (NEM) data released in June this year, Australia’s electricity supply is becoming cleaner: electricity from renewable sources has risen by nearly 23 per cent and natural gas power by more than 5 per cent since the previous twelve months to May 2012. At the same time, the use of brown coal has fallen by about 12 per cent and black coal by more than 4 per cent. Generation by Australia’s seven biggest coal-fired power stations has fallen by over 13 per cent. Structural changes driven by the high Australian dollar, rising electricity prices, introduction of energy efficiency measures, increased home installations of solar photovoltaic (PV), and the Renewable Energy Target are key drivers of this change. However, early indications are that the carbon price is playing a supporting role by make renewable energy even more competitive compared to fossil-fuel generation. As the price becomes more embedded in longer-term investment decisions the role of the carbon price will increase.

Electricity price-rises—perception and reality:

For businesses and consumers alike, electricity prices have risen sharply for several years—more than 40 per cent in the last few years. On average, more than half of this rise is the result of network upgrades, including the replacement of aging infrastructure. Despite the recent increases, however, when adjusted for inflation, electricity prices are about the same as they were a generation ago.

Yet, according to the Australian Industry Group, there is still a false perception amongst many in business that the carbon price is the biggest contributor to rising prices.

The biggest of [the] …pressures [on prices] is the rising cost of electricity networks, the poles and wires that deliver power. The high-profile of the carbon tax appears to have led to some over-estimation by businesses of the specific impact of the carbon tax on energy prices…

For residential retail customers, the carbon price accounted for around 9 per cent of power bills in 2012–13, or between about $2 and $4 extra per week, depending upon the state or territory. It should be noted that the carbon price is unlikely to materially increase bills any further in the next few years, although prices will continue to rise for reasons that have nothing to do with the price on pollution.

An upshot of recent price rises—and scare-campaigning by some in politics and industry—may be the spread of a more energy-efficient ethos: in 2012, approximately 90 per cent of Australians did something to minimize their power bills, according to the Australian Bureau of Statistics. Such changes in consumer and business behavior are likely to help cushion the impact of any future price-rises.

The cost of living has not skyrocketed:

 Before 1 July, 2013, the Australian Treasury predicted that the carbon laws would add 0.7 per cent to the Consumer Price Index, while CSIRO and global consulting firm AECOM conservatively predicted inflation at 0.6 per cent, given 100 per cent cost pass-through. This was part of a study for The Climate Institute, Choice, and the Australian Council of Social Service (ACOSS). The impact of the carbon price on particular prices is barely discernible. Indeed, the ABS has said it is unable to discern any impact against normal variability in consumer prices. One estimate, by Westpac Economics, suggests the reality is that the carbon price has added just 0.4 per cent to the Consumer Price Index.

For the vast majority of Australian households, the increase their cost of living has been very small and this will be covered by the assistance package associated with the scheme. According to independent analysis, for a low-income family of four, for instance, assistance is, on average, around $31 per week; for a single pensioner, it’s a little over $19 and for a middle-income family of four, it’s about $13. Federal assistance was projected to leave the large majority of households better off.

 Looking forward

The hyperbole that characterized the twelve months to 1 July 2013 has largely given way to reality. The carbon laws have not undermined Australia’s economic performance nor have they raised the cost of living substantially.

What is more, the package of carbon laws is contributing to emissions from electricity falling, the energy mix shifting in favor of renewable and cleaner fuels, and energy use is becoming more efficient. Low-carbon investment is flowing—the carbon price at work using money raised by the price on pollution, over six years, $946 million is committed to maintain stocks of carbon in bush land, and to enhance the resilience of natural systems to climate change. In the first round of the Biodiversity Fund, around $270 million has been allocated to more than 300 landscape rehabilitation and restoration projects around the country.  Hundreds of firms are investing in energy efficiency, cleaner manufacturing, and innovative renewable energy projects, such as geothermal and solar-thermal. Many have received grants drawn from monies raised by the carbon price. Federal clean technology funding programs total $1,200 million over the next few years. Already, companies with household names like Arnott’s, Bundaberg Sugar, Bega Cheese, CSR, and Coca-Cola, together with many others, have received public grants leveraging considerably more private investment.

Meanwhile, the Carbon Farming Initiative is seeing the big end of town investing new money in regional and rural communities. Between them, BP Australia, CS Energy, CSR, and Energy Australia have purchased more than 322,000 Australian carbon Credit Units, representing more than $7 million in low-carbon projects, such as sustainable forestry, cleaner livestock production, better landfill operations, and savannah management. Overall, Australian Carbon Units and ACCUs purchased by fossil-fuel power stations were worth $39 million in June 2013.”

President Obama has recently outlined his policy on climate change and Carbon pollution reduction measures.US and the rest of the world can learn lessons from Australian experience on how low Carbon economy can be achieved without compromising an economic and industrial growth. In fact low Carbon economy can create millions of jobs and a sustainable future. The same polluting Carbon can become a source of cheap Hydrogen by innovative gasification technology. Innovation is the key to achieve a sustainable energy mix between renewable and fossil fuels.

 

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