Interesting question...

https://www.huffingtonpost.com/entry/why-renewable-energy-will-replace-fossil-fuels_us_596cad4de4b022bb9372b313

https://developmenteducation.ie/feature/the-energy-debate-renewable-energy-cannot-replace-fossil-fuels/

https://alternativeenergy.procon.org/view.answers.php?questionID=001244

https://worldview.stratfor.com/article/when-renewables-replace-fossil-fuels

http://www.ecology.com/2011/09/06/fossil-fuels-renewable-energy-resources/

https://www.friendsofscience.org/assets/documents/Renewable-energy-cannot-replace-FF_Lyman.pdf

Thank you Prof.

http://www.debatingeurope.eu/2017/02/15/can-renewables-ever-replace-fossil-fuels-100/#.WnlB4byWa1s

link may useful ..

Pulling all countries together towards rallying to replace fossil fuel is an impossibility. As you are already aware, some of them are questioning the science linking global warming to releases of CO2 from fossil fuels. How do you covert such doubting Thomas' towards the common goal of transiting to renewable fuels. Irrespective of my skepticism, however, the cause my not be lost. Since there are many nations that believe in transition to renewable energy sources, hope exists that rallying the nations with such a common mind, shall help foster the zeal towards the renewals. And, such is what is needed, for, remember: the goal is towards reducing CO2 emissions, but, not necessarily eliminating the emission. As such, if some countries -and very many of them, come together towards the said transition objective, then the goal to reduce the emissions, can be achieved.

Thank you Prof. you are absolutely correct. All inventions and technology is the efforts of human being from stone age to present. All nationalist wants comfortable and easy way to live including growth of national GDP. The fact is that for good result for protecting natural environment for future generation we can also sacrifices the bed result. So, if all people come ahead in this field with first priority rather than the political, economic and social benefit may be the case will be nearer the result.

Thank you very much

I don't think so it is going to be happened in near future. Yes, but of course it will contribute and will have it's role. The renewable energy resources are not so persistent like fossil fuels are. The utilization of renewable energy will not only fill the energy gap but will be the solution towards many environmental problems. So as to ultimately, renewable energy will make it's place and would become necessary to hang on there.

Asim.

Thanks

Dear Ramesh and colleagues!

I have a contribution in this issue of challenges in the transformation from conventional to renewable energy. I proposed a road map and a growth law of renewable compared to that Moore Law for the growth of the transistor count in the integrated circuit.

Please follow the link:https://www.researchgate.net/publication/320613839_From_conventional_to_renewable_energy_transformation_challenge

to see the paper.

I am sure that you will like it.

Best wishes

Thank you Prof.Your contribution in this issue is quite useful and relevant.

Thanks

It seams impossible to have a situation in which there is no emission of CO2 (we would have to stop breathing o leave a mask that absorbs CO2). The aim is that global emissions not increase, and be reduced where possible. This must be done by alternative and renewable energy, biofuels produced from sources who reabsorbe the same amount of CO2 as produced and do not interfere with edible crops production or are not obtained as a result of deforestation, CO2 capture followed by sustainable underground storage and/or circular systems reconverting CO2 into useful products (the tendency should be that for example every coal power plant would have a CO2 capture and reuse system), energy efficiency and savings of any type of energy consuming process or private use, etc., etc.

Correct, Thanks prof.

I think so but it needs more efforts on the scientific, economic and politic planes and also it needs some time to replace the energy systems working nowadays in many developing and poor countries with the new systems depending on the renewable energy which need to build infrastructure systems.

Yes thanks a lot but developed countries are more responsible for much GHG emmission

Hello,

I guess we all know that the full reliance on the renewable and semi-renewable (nuclear) sources seems to be the only feasible choice for significantly reducing the human caused GHG emissions due to burning fossils. These emissions have severe impacts on the ecological system of the Earth. With the depletion of fossil fuels, it seems that we have no other choices provided that feasible bulk energy storage will be available. On the other hand, do we really expect that stopping the use fossil fuels will stop climate changes or restore its desired conditions?

Please let us analyze the causes of the climate changes. The causes include high GHG levels, and the surrounding space of the Earth. The GHG emissions are partially caused by human activities, while the rest of emissions are produced naturally due to, for example, volcanic eruptions and similar phenomena. Some studies show that the postion of the Earth within the galaxy and within the universe has significant impacts on the Earth ecological system and its climate. Therefore, extremely long term cyclic changes affect the earth with the changes in its position. Probably, we are facing a destiny! As a conclusion, we need to shift to renewables for energy security and for enhancing the environment, but the strong impacts of that shift on the climate is somewhat doubtful.

Best regards

Thank you Prof. for your valuable suggestion. It is correct and all should ensure to shift to renewable s for energy security.

I dont think so. There are so many things to be done before every country reach such a stage. I think technology will limit some of the countries to completely replace fossil fuel. Much as I agree with you that renewable energy is the way to go but we have to develop the right and friendly technology for each country and then think of replacing fossil fuel. Think of the Poor countries who rely heavily on biomass cooking energy, what is happening is not sustainable and will never be sustainable without a friendly energy technologies. The population in these countries are increasing very fast so is the demand for the biomass from the forestry which leads to deforestation and degradation. Unless we innovate proper technology in these countries we will never replace fossil fuel completely.

Definitely Prof. until and unless we must innovate renewable more renewable to replace fossil fuel.

Thanks

Why to reduce fossil fuel combustion COMPLETELY ?

Until the beginning of the industrial revolution, 3 centuries ago, CO2 went up and down between 180 and 280 ppm, and every peak corresponded to the end of an ice age and he beginning of a warm age.

https://upload.wikimedia.org/wikipedia/commons/1/1c/Carbon_Dioxide_400kyr.png

The last 100 centuries were at the peak of CO2 and of temperature, which favoured the development of civilization. In the next age, without the buildup of CO2, we would assist to a new drop of CO2 and of temperature, and a new ice age which would stop our civilization.

We could stop the increase of CO2 without letting it drop again. Some CO2 content seem desirable, to keep the present climate stable

On 12 December 2015, the 21st Session of the Conference of the Parties to the United Nations Framework Convention on Climate Change in Paris (COP 21) ended with an agreement ratified by 55 parties among the 197 participating, with the commitment to make their best efforts to avoid that the global temperature would increase 2C or more above the pre-industrial era by reducing their emissions to the atmosphere, and to report regularly on their emissions and implementation efforts. On 20 April 2017, 143 parties had ratified the Paris Agreement.

It does not mean that CO2 must disappear. It means that where economically possible it should be reduced. This is and will be done by substituting progressively fossil fuels by biofuels and renewable electric power. Also that high CO2 emitters like coal power plants should install CO2 capture for reuse (for example transforming it into chemicals in a circular economy) or underground storage. And in a general way by improving energy efficiency in all sectors.

Yes thanks Prof. countries are not quite serious for implementing the agreement.

Capturing CO2 from stack emissions is expensive (and it creates the problem of where to put it). Since coal is the cheapest fuel, we will keep using it and emitting CO2 until it will be forbidden.

For the moment, we could start using natural gas, which cuts by half CO2 emissions. I am proud to say that my country is ahead on that route.

Definitely Prof. In our country our source of electricity depend on hydro power. 97% source of electricity is from hydro power but use of fossil fuel is havoc in transport sector. Use of diesel, petrol, biomass is on the route. 67% rural area is depend on forest resources for cooking and heating purpose. Electricity is only used for other purposes. Thus use of renewable energy is also essential to reduce CO2 combustion.

Not all countries dispose of sufficient natural gas and transportation over long distances is costly and energy consuming, and increases the risk of leakage. Natural gas has a much stronger greenhouse gas effect than CO2. Some interesting results of research demonstrate that CO2 Capture can be made more economically (for example research at the University of California, Berkeley) and more recently that it is possible to convert it again in useful chemicals. (see my publication: Innovative Chemistry is required to fight Climate Change, René Aga Van Zeebroeck, Dr.Sc. (SECOT), Industria Química, Nº 23, 2015, Achema 2015 edition.)

Attesting a yes will be a hypocritical. Majority of global south nations depend on fossil energy. Many skeptics find it as a strategy to open up uptake of green technology to curb emission of CO2. Equally we can harness equitable and sustainable use of clean coal and renewables.

Thanks

At last, we will be obliged to rstrict dramatically our use of fossil fuels and to recur to hydrogen made by renewable energy, unless we find a way of getting rid of CO2.

A way will be found to store hydrogen in a practical way, e.g. recyclable chemical compunds like bortes.

Or CO2 could be kept as an intermediate stage to more practical fuels, e.g. combined with hydrogen to higher hydrocarbons (CO2+4H2=CH4+2H2O), but CO2 produced by combustion shall be recovered from car exhausts and chimneys and recycled. We must get used to it.

Thank You Prof.

Eventually some form(s) of renewable energy will replace fossil fuels but it will take at least 30 years and the form of renewable energy that will replace fossil fuels is yet to be determined. CO2 capture could be a reasonable bridge to a renewable future - or we may keep burning fossil fuels - and suffer the consequeces.

Thanks Prof. It could be?

Ramesh, What I meant by " CO2 capture could be a reasonable bridge to a renewable future " is that it will only be a viable option if society is willing to fund it. So far there has been very little interest in developing sequestration sites and no interest in building pipelines to move CO2 from where it is captured to where it will be sequestered. Sequestrtion of CO2 is a necessary step to make electric powered vehicles "clean'. Electric powered vehicles are only "clean" if the source of electric power is also clean.

Yes Sir off-course, I think developed countries are more responsible for more emission of CO2 rather than serious implementation of CO2 sequestration. Most of developing countries are depending on traditional source of energy and depend on electricity generated through hydro power as green revolution. COP 21 however addressed to the issue lightly with allocation of funding also; but parties interest and implementation is very poor. As your concern nobody are serious in this issue; all scientist and interest of groups are running for impacts assuming temperate increase, polar ice issues, glacier and sea level rise and also somewhere arsing future assumption and predictions. But for mitigation it become negligible. So combining the issues with strong mitigation country by country focusing on plantation, reducing use of fossil fuel and promotion of green energy seriously could be fruitful for future generation and degrading natural ecosystem.

Ramesh, Yes indeed developed countries are most responsible for ghg emmissions and coastal/poor countries will most likely disproptionately suffer the consequences.

https://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions#/media/File:Co2_cumulative_emissions_1970-2013.svg

Thanks

Thanks

Any solution to avoid new CO2 emissions is expensive. Most reasonable and richest governments will have to finance extra costs involved, so accepting a burden to their economies. Few will accept that.

One solution could be reducing the cost of energy by renewable sources, so that fuels produced from electrolytic hydrogen become competitive.

The goal is not far.

Absolutely, cost of renewable is more expensive for example generation of hydroelectricity from remote locations

I think cost competitive electrolytic H2 is a long way off. Producing enough eletricity to eliminate coal fired power generation should be the first objective. H2 is actually produced quite effciently (70-80%) by Steam Methane or Autothermal Reforming and all of the CO2 produced can be captured relatively easily - if there is a proper incentive to do so.

Thank you Prof. Yes that could be.

In fact, it is much easier to produce hydrogen from fossil fuels.

But it creates the problem of getting rid of CO2, a huge quantity of CO2.

Fixing it with vegetables seems insufficient (I am thinking of how much CO2 I generate each year with my car and heating my home).

Maybe the only possibilitiy is capturing CO2 as clathrate and sinking it deep under sea. But would environmentalists agree ?

Or we should adopt a hydrogen economy. Maybe combining hydrogen from renewable energy sources with nitrogen to ammonia, a practical fuel. Ammonia is more dangerous than liquid hydrocarbons, but safety problems can always be solved.

CO2 capture and use is object of much research around the world. New solvents and adsorbents are being developed. Storage is not the ideal solution. It is useful for enhancing oil recovery from oil fields. The best solution is to reconvert CO2 into valuable chemicals and is object of research. Solutions will come from "green chemistry". CO2 capture and use will be part of an article I am preparing and will be published in the Spanish magazine Industria Química, special edition in English for ACHEMA 2018, the International Fair of the Chemical Industry in Frankfurt, Germany. After it is published I could make it available on Research Gate.

If we could afford to sequster "large "quantities of CO2; how much would we need to remove from the atmosphere to level out the concentration? Say there is 407 ppm CO2 in the sky today, and I wanted to remove 10 ppm. Am I far off in my calculation to estimate the quantity to remove is 1.2 x10^14 kg of CO2?

... Do you have a place to store that?

About 30 years ago all H2 plants caputured the CO2 they produced with a Benfield , CatacarabMerox or some other min based srubbing. Unfortunaelty the vast majority of this CO2 was released to the atmosphere. The carbonated beverage industry was the largest actual user of this CO2 and some of it wasused for enhanced oil recovery. Capruring CO2 from an SMR reformer is easy. Transportatation and storage is a problem at most locations.

Chris, the calculation is easy, but I would be afraid of results.

There is 1 kg of atmosphere over each square cm. of ground.

Figure to absorb 100 ppm of CO2 from the atmosphere (not more, to avoid a new Ice Age); it means 0.1 gr. of CO2 absorbed for each cm² of ground, 1 kg every m², 1000 tons every km². And the diameter of Earth is 12000 km...

Giorgio, interesting... So if the surface area of our planet is 5.10 *10^14 m^2, then to remove 100 ppm we need to handle ~5.10 *10^16 kg of CO2.

Hmm... That is alot. And unless we use nuclear power; we will create alot of CO2 trying to recover that.

What would be the volume of CO2 gas at say.... 10 Atm?

Hmm..

So, Rick Manner, per your comment above - to replace coal generating power is easy. We have that technology now; with no CO2 emissions. Should that not be the first priority? I have not heard one popular Global Warming advocate make this a priority. Are there some calling for different energy generatng technology?

Chris,

Actually replacing coal generating power is not easy. Here is the EIA projection of coal use for th next 20 years. It levels off but it does not go down by much. Coal is abundent and will most likely continue to be used to produce electricity unless there is a major breakthrough and/or policy change that significantly reduces the cost and increases the availability of renewable power.

https://www.eia.gov/outlooks/ieo/pdf/0484(2017).pdf

The science of the thermodynamics for the renewable energy will not be ready for the world in the next 40 years. Because, the science of materials and electronics has to change .

Rick, I understand that.. but wind and solar will never substantially replace steam-turbine generated power. People know this. There is a technology that currently works (24 hours a day). Why don't climate change enthusists make this a top priority? Obama could have made a policy change to move this forward, and start to eliminate fossil fuels. Most people would back it.

Federal policy and regulation changes can make this happen quickly - like the race to the moon.

I feel that they are not sincere if they don't back a sure thing... Unless they have other priorities.

As they say, "the clock is ticking".

Chris

Obama made some progress but he did not have control of congress long enough to do much more. The Republican party has found that denying climate change and embracing racism will get them a lot of votes.

Also there is no clear solution yet. Solar and Wind are not the complete solution - at least not yet. All of the potentially viable solutions are still extremely expensive and would likely cause a recession if implimented quickly. The clock is indeed ticking. It is probably time to get serious about mitigation and adaptation.

Well, I think it is better to program for a summer house in Greenland...

House prices should be low there. And white bears should be extinct by then.

Actually I was refering to nuclear power to run steam turbines. I agree with Ayodele that the technology is not cost effective and cannot produce 24-hr energy for manufacturing. Racism doesn't have anything to do with the Climate Change debate or renewables. The issue is whether the "science" is settled, and the competing technologies are viable and cost effective. Natural gas is better than coal in a number of ways, and the market place has been using it more and more. Nuclear power is the cleanest alternative, but really should not be built close to a fault line.

Thanks, This is best alternative but developing countries are unable to plant nuclear power

Nuclear Fission has lost the race and fusion never got out of the starting box. It may have been different if the iming of "The China Syndrom" Book/movie, Three Mile Island and Cherbobyl was better but unfortunately the US and probably most of the world gave upon Nuclear Fission power generation around 1979. However, China and India (and Russia I think) are sill building nuclear power plants and there is some activity in Europe as well so there is still some hope that nuclear will contribute to future energy supply but the cost may still too be too high

Here is the unfortunat 2009 conclusion of the MITEA study regrding the future of nuclear:

Conclusions The central premise of the 2003 MIT Study on the Future of Nuclear Power was that the importance of reducing greenhouse gas emissions, in order to mitigate global warming, justified reevaluating the role of nuclear power in the country’s energy future. The 2003 study identified the challenges to greater deployment and argued that the key need was to design, build, and operate a few first-of-a-kind nuclear plants with government assistance, to demonstrate to the public, political leaders, and investors the technical performance, cost, and environmental acceptability of the technology. After five years, no new plants are under construction in the United States and insufficient progress has been made on waste management. The current assistance program put into place by the 2005 EPACT has not yet been effective and needs to be improved. The sober warning is that if more is not done, nuclear power will diminish as a practical and timely option for deployment at a scale that would constitute a material contribution to climate change risk mitigation.

http://web.mit.edu/nuclearpower/pdf/nuclearpower-update2009.pdf

Thanks Prof.

When compared to nuclear, renewable energy sources are safer and less expensive.

No need of huge solar fields, just grow palms and burn their oil.

Yes Prof. but all countries are unable to plant nuclear power i.e. developing countries

Interesting MITEA study. Thank you.

So the policy decision to advance under-developed and expensive solar and wind, has delayed the solution to the problem. So engineers can't help where there is no will, and no desire to really solve the problem. The space shuttle Challenger launch failure is like this... To avoid the disaster a technical person should have been the final authority to approve the launch, not the program managers.

France dirives 75% of its power from nuclear. We only do about 19%. We could easily boost our use by a factor of 2, and then replace that capacity in 30 years (if and) when the other technologies mature. I don't think fear is a good way to drive policy since nuclear is the "greenest" solution to CO2 reduction. If you can't remove the CO2 (plants do that) we need to stop making it. The US can do it, so we shouldn't let advocacy groups select the "best" technology.

Tick, tock...

Just a comment. There are not enough uranium mins to cover our energy needs for a long time

Oil from palms, OK. But not by quiting forests or eadable food lands.

In November 2016, the European Commission proposed a revised Renewable Energy Directive which includes updated sustainability criteria for biofuels used in transport and bioliquids, as well as solid and gaseous biomass fuels used for heat and power. The reason was to ensure that the use of biofuels and bioliquids is done in a way that guarantees real carbon savings and protects biodiversity. Only biofuels and bioliquids that comply with these criteria can receive government support or count towards national renewable energy targets. The criteria are also used to authorize the import of biofuels from non member states. 

Then why did the US approve the sale of 20% of our resurves to Uranium One corp.??

Chris, Here is some information about Uranium One:

https://www.factcheck.org/2017/10/facts-uranium-one/

Chris, Re- the MIT study. To be fair fear wasn't the only issue that prevented the development of Nuclear energy. Cost was also a major factor. Although you could reasonably argue that fear is a major contibutor to the high cost.

Rick, I grew up in New England, near the Seabrook Nuclear plant. Contsruction was between 1976 and 1986, and was marked by an explosion of federal regulations for the design of these types of facilities which resulted in design changes and contruction change orders. This caused massive delays and cost over runs (final cost was 2x estimates). Fear and environmental activism slowed completion and added sinnificantly to the cost of completion. Meanwhile the cost of electricity spiked since all the regional power companies had stock in Seabrook and were buying power off the Canadian grid till it came on-line. My bill was about 40% or more compared to other parts of the country.

"Seabrook Station generates approximately 40 percent of New Hampshire's total electricity, and its emission-free operation helps avoid the emission of nearly 4 million tons of carbon dioxide annually, which is the equivalent of taking almost 700,000 cars off the road." info from : https://en.wikipedia.org/wiki/Seabrook_Station_Nuclear_Power_Plant

Chris,

I remember the Seabrook protests very well. I was living in Boston at the time (1975-78) . New Hampshire governor MeldrimThompson was a lighting rod for the protesters because he claimed at one point that he also wanted the New Hampshire national guard to have nuclear weapons.

In the Seventies nuclear power (and wapons) were a real promise and renewable sources of energy were just a chapter in books. (I have a collection of books of that kind, written when oil price was high, and atmospheric pollution too). The situation has changed since then. Today speaking of nuclear power is almost blaming.

But the recent development of electric cars caused a competition: will renewable sources be able to supply enough energy for electric traction, or will somebody begin to propose again nuclear plants ?

Anyway Chinese are buying lithium mines around the world.

(Personally, I do not love batteries; too heavy and expensive. I prefer hydrogen and fuel cells, But the problem remains)

Giorgio,

I agree both electric cars and hydrogen vehicle have both promise and problems. One or both of them have a chance to replace gasoline/diesel powered vehicles. But will take at least 20 years for it to happen and it is too early to give up on either technology.

I would like the hydrogen alternative also, except it generates CO2.

But if you charge your electric car with power produced by a fossil fuel plant, are you not creating a carbon foot print? Nucler power to an electric car is without a carbon component. Coal power electricity to an electric car is just like driving on coal.

There are pros and cons for both H2 and electric vehicle. Incremental H2 and electricity are both currently produced by fossil fuel. CO2 capture can be performed at both H2 plants and power plants. I believe saftey is more of an issue for H2 than electric vehicles. I think electric powered vehicle are currently ahead of H2 vehicles but that could change,

As far as I think, it is not completely possible to remove the use of combustion of fossil fuel and to use only renewable energy in all circumstances. There are some problems:

1. Most important problem is the feasibility. All the circumstances like all types of combustible vehicles, Jet engines can be handled by renewable energy.

2. The cost of using renewable energy is comparatively higher than fossil fuel.

3. The use of renewable energy depends on environment. So, it is uncertain.

4. Large amount of power production is very hard by using renewable sources.

Hi Ramesh

This is interesting. You may have a look at the following publication:

Article Assessing the potential of CO 2 utilization with an integrat...

The article does take into account the scenario when fossil fuels like gasoline/diesel are replaced by green fuels like methanol/DME.