Healthy planet action coalition meeting August 10, 4:30 PM EDT.
H simmens
Author of A Climate Vocabulary of the Future
@herbsimmens
HerbSimmens.com
H simmens
Healthy Planet Action Coalition meeting tomorrow August 10, 4:30 PM EDT.
rob...@rtulip.net
Healthy Planet Action Coalition meeting this Thursday August 24, 4:30 PM EDT (= 9.30 pm UK = 6.30 am Friday Australia AEST )
Meeting link is https://us02web.zoom.us/j/88954851189?pwd=WVZoeTBnN3kyZFoyLzYxZ1JNbDFPUT09
Chris Vivian: Ocean Carbon Dioxide Removal and Governance
HPAC has great pleasure in welcoming Dr Chris Vivian to present at this week’s meeting. Chris is a regular participant in discussions about effective responses to the climate crisis. His talk on Ocean Carbon Dioxide Removal and Governance will introduce these themes to open dialogue with meeting participants. Chris is a member of GESAMP, the Joint Group of Experts on the Scientific Aspects of Marine Protection. His resume below is from http://www.gesamp.org/about/members/chris-vivian
Chris Vivian has worked for Cefas, the Centre for Environment, Fisheries and Aquaculture Science, an agency of the UK Department for Environment, Food and Rural Affairs (Defra), and its predecessor since 1986. He received a BSc in Geology and Oceanography and a PhD in Marine Geochemistry at University College of Swansea in Wales, followed by an 18 months research fellowship at Imperial College, London. He has specialised in advising on the impact of human activities on the marine environment, particularly the disposal of wastes at sea. He has had a long involvement with the OSPAR Convention and the London Convention/London Protocol. He was the Chairman of the Scientific Groups of the London Convention and London Protocol from 2008 to 2011 and the Chairman of the OSPAR Convention’s Biodiversity Committee that dealt with species/habitat protection issues as well as the impacts of human activities from 2006 to 2010. Chris is a member of the Central Dredging Association (CEDA), the International Navigation Congress (PIANC), the Estuarine and Brackish Water Science Association (EBSA) and as a Fellow of the Institute for Marine Engineering, Science and Technology (IMAREST).
Hope to see you there
Robert Tulip
Jim Baird
Dr. Vivian pointed out a today’s meeting science moves on.
The thing is the paper the GESAMP claimed, its based its assessment,” that implemented at a large scale TG would be temporary, regionally heterogeneous and present the type of termination risks usually associated with solar geoengineering approaches, was a work of science fiction from the outset.
And what the GESAMP said verbatim, on page 76 of the GESAMP REPORTS & STUDIES No. 98 – MARINE GEOENGINEERING was:
“Heat pipe OTEC (also called ‘Thermodynamic geo[1]engineering’) to cool surface waters could effectively reduce warming associated with climate change but implemented at a large scale such effects would be temporary, regionally heterogeneous and present the type of termination risks usually associated with solar geoengineering approaches (Kwiatkowski et al., 2015). Large scale deployment of OTEC heat pipes for purposes of thermodynamic geoengineering would be potentially disruptive to the marine environment considering that, by definition, it would significantly reduce sea surface temperatures on a regional scale while having all the same localized environmental impacts as conventional OTEC.”
The Kwiatkowski paper modelled a vertical diffusivity in the top 1000 m of the water column at a rate of 60 cm2 s-1. Whereas Thermodynamic Geoengineering would actually upwell heat, not water, at a rate of 1 cm/day. In other words, over less than 1//5,000,000 of the rate of perturbation modelled.
Furthermore the authors of this paper where admonition in a paper An Evaluation of the Large-Scale Implementation of Ocean Thermal Energy Conversion (OTEC) Using an Ocean General Circulation Model with Low-Complexity Atmospheric Feedback Effects by Jia et al that “Kwiatkowski et al. used a fully coupled (atmosphere, land, ocean and sea ice) model, the Community Earth System Model (CESM), to explore the consequences of boosting the background vertical diffusivity of the top 1000 m in the ocean by a factor of 600. They argued that the resulting disruption of the thermocline from such greatly enhanced mixing could be regarded as a proxy for the large-scale effects of technologies such as OTEC, which rely on seawater properties from different vertical layers using pipes and pumps. Although OTEC is the first word of the article, the proposed numerical experiments may not be applicable in the context of OTEC. On one hand, the upper-ocean vertical diffusivity is altered everywhere, while OTEC could only be developed in selected tropical areas, over about a third of the whole ocean. Moreover, the magnitude of the imposed upper-ocean vertical diffusivity would preclude the production of OTEC power anywhere since the vertical temperature difference available in the disrupted thermocline is only a few degrees, far shy of the 20 ◦C typically considered for OTEC feasibility.
In spite of Dr. Vivian’s claim the GESAMP has no reason to retract its assessment of Thermodynamic Geoengineering, I submit anyone with a technology that it wishes to advance, yet is confronted by the situation in which I find myself would also no doubt scream bloody murder. Particularly if they were convinced their children and grandchildren were facing a risk that they are certain could be avoided.
Regards
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Tom Goreau
The GESAMP statement gets it ack-bassward!
They said that TG was a risk because it would lower ocean surface temperature!
That’s the biggest benefit!
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Chris Vivian
Tom,
No, we did not get is ass-backwards as very widespread significant reductions in temperature could be disruptive albeit they may seem desirable in current circumstances.
However, Jim Baird was objecting to the first part of the text ““Heat pipe OTEC (also called ‘Thermodynamic geoengineering’) to cool surface waters could effectively reduce warming associated with climate change but implemented at a large scale such effects would be temporary, regionally heterogeneous and present the type of termination risks usually associated with solar geoengineering approaches (Kwiatkowski et al., 2015)”. This text was derived from that paper where it said “Such studies have also indicated that the termination of processes bringing warmer surface waters into the deep ocean has the potential to cause near surface temperatures to rise higher than they would have if pipes had never been implemented (Oschlies et al 2010, Keller et al 2014)”.
Chris.
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Ye Tao
How surface temperature reduction is achieved makes all the difference from a planetary perspective. Helpful ways to reduce surface temperature include reducing global source rate and increasing global sink rate. Internal shuffling of heat to expose a temporarily cold surface invites more heat in. The result is a net increase in Earth's Energy Imbalance leading to an increased rate of surplus thermal energy accumulation below the top of the atmosphere. The approach is fundamentally self-defeating.
Ye
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Tom Goreau
You can’t say that TG is risky because surface temperature reduction is “disruptive”: mass mortality from heatstroke is underway in most ecosystems!
TG is needed to prevent extreme heat waves, which is measured by Coral Bleaching HotSpot analysis.
Surface temperature reduction is essential to prevent mass mortalities of sea life and imminent extinction of coral reefs.
Right now we are facing accelerating coral death from high temperatures, also of shallow water marine organisms in many other habitats, and only a method that reduces surface temperatures can save them.
See just posted below from Mexico, Florida is as bad and so are many reefs all around the world.
It is impossible to get data since dive shops won’t report bleaching because it is bad for business.
Experts: Mexican corals face massive death due to rising water temperatures
Aug 24, 2023 - 08:47 PM
TOPICS: Mexico
The massive death faced by Mexican corals due to the increase in water temperature represents a serious national problem, experts from the National Autonomous University of Mexico (UNAM) agreed on Thursday.
Mexican researchers Lorenzo Álvarez Filip and Juan Pablo Carricart Ganivet, from UNAM's Institute of Marine Sciences and Limnology (ICMyL), pointed out that the problem is due to the sum of two important factors: the climate crisis and the phenomenon of El Child.
“If we put it from our perspective, this event is being catastrophic because we are losing a lot of corals,” emphasized Carricart Ganivet, an academic at the ICML Coral Reef Sclerochronology Laboratory.
The experts explained, in the conference entitled "Mass death of corals in Mexican reefs?", that the water surrounding the corals has maintained a constant temperature of between 32 and 33 degrees Celsius for more than 15 weeks, which has caused the bleaching and death of corals in the reefs of the Pacific, Gulf of Mexico and Caribbean coasts.
Álvarez Filip said that the first cases of coral bleaching were detected off the coast of Huatulco, in the southern Mexican state of Oaxaca, at the end of May.
In this same region, large areas of the reef had died by August and they warned that the same situation is reported in other parts of the Mexican territory, such as in the states of Baja California, Jalisco, Guerrero and Veracruz.
Filip explained that only in Puerto Morelos, in Quintana Roo, in the Mexican Caribbean, "the corals were already weakened by various factors", such as the stress of enduring high temperatures for so long, suffering from a disease that caused massive deaths in past years, known as the "white syndrome", and the high levels of nutrients that human beings throw into the water daily.
The experts also stressed that the loss of corals will have a devastating impact on the environment and the economy, as coral reefs are home to a wide variety of marine life and play a vital role in protecting coastlines from storms and erosion. .
In addition, they explained that "the tourism industry in Mexico also benefits from coral reefs," with millions of tourists visiting the country each year to snorkel and dive among the colorful reefs, as well as those seeking scenic beauty, with turquoise colors in the waters and white sand.
The researchers asked the Mexican government to take measures to address climate change and protect coral reefs with greater amounts of investment in projects that allow monitoring of what is happening in the area.
In addition, they considered it necessary to make the population aware of the effects that their actions have on marine ecosystems, and supported that decisions be made based on scientific research.
Jim Baird
Global warming is trapped solar energy that can go anywhere and mostly into the ocean and towards the poles.
Thermodynamic Geoengineering passes the surface tropical heat through a heat engine to produce engine and removes 92.6% to deep water from where it diffuses back to the surface where it can be recycled at least 13 times. This is close to 3000 years of global warming respite. To that end he increases the global sink rate.
Jim
Ye Tao
When TG passes the surface heat into deep waters, upwelling IR from the surface reduces as Earth's natural Planck feedback gets artificially held back. Upwelling turbulent fluxes also reduce. Rate of heat accumulation on the planet will increase.
Hiding heat in the ocean does not create a global sink; it is
heat storage that will guarantee a future, 'explosive'
destabilization.
Ye
Anton Alferness
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Ye Tao
Does not seem likely based on a back of the envelop assessment.
Jim please check:
Assume an annually averaged mixed layer thickness of D=50m.
Assume the temperature differential is DeltaT=20C between surface
and deep waters. Assume a background water surface temperature of
T_surf = 300K. Assume a background upwelling IR_upwelling = 400
W/m2. Assume that we move 1m3~1ton of seawater down and replaced
it with cold water.
The amount of thermal energy buried equals 3850(J per kg per
degreeC)*1000(kg)*20(degreeC) = 77MJ. The reduction in upwelling
IR is independent of area over which this water mixes once lifted
to the ocean surface. This is because temperature change to the
surface layer scales inversely with the size of the final mixed
area, while upwelling IR power scales with the area, so the two
effects cancels.
For a lifted cube of cold water 1m on each side, its impact on
surface water IR emission is Delta IR_upwelling = 4 DeltaT
*IR_Upwelling/ (T_surf * D) = -2.1 Watt.
At the small scale, downwelling IR would be negligibly impacted, resulting in a net increase in downwelling energy flux. The 77MJ of buried energy is eroded away within 77MJ/(32E6 sec/yr *2.1 J/sec) = 1.1 year. If we included reduced evaporation and sensible heat, the temporary benefits erodes within 1 year.
Let's say the goal was to prevent further global warming until
other approaches ramp up, then TG would have to operate in the
nearterm at 1000TW = 1E15 Watt. This requires pumping 13 Mton of
water per second, or 420 trillion m3 of water the 1st year, which
is 100 times the total global freshwater consumption, everything
including agriculture and industry. In 10 years, one would have
to pump 1000 times the total global freshwater consumption because
the benefit erodes every year.
Ye
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Tom Goreau
Yes, precisely, cooling the surface ocean buys us centuries to restabilize CO2 at safe levels by Geotherapy.
Tom Goreau
No, because TG pumps heat downward with a working fluid, it does not pump surface water itself downward.
From:
Mike Williamson <mi...@wassoc.com>
Date: Friday, August 25, 2023 at 3:14 PM
To: Tom Goreau <gor...@globalcoral.org>, Chris Vivian <chris....@btinternet.com>, 'Jim Baird' <jim....@gwmitigation.com>, rob...@rtulip.net <rob...@rtulip.net>, 'healthy-planet-action-coalition' <healthy-planet-...@googlegroups.com>,
'Planetary Restoration' <planetary-...@googlegroups.com>, 'via NOAC Meetings' <noac-m...@googlegroups.com>, 'Healthy Climate Alliance' <healthy-clim...@googlegroups.com>, 'Carbon Dioxide Removal' <carbondiox...@googlegroups.com>
Subject: Re: [CDR] HPAC meeting with Chris Vivian on Ocean CDR: August 24, 4:30 PM EDT.
The cooling benefits of bringing deep water to the surface may be offset by the release of carbon dioxide and methane as that water warms.
To view this discussion on the web visit https://groups.google.com/d/msgid/CarbonDioxideRemoval/BY3PR13MB4994FA5085526911C707D313DDE3A%40BY3PR13MB4994.namprd13.prod.outlook.com.
Jim Baird
Wrong.
At scale TG would offset of the offgassiing of 4.3 gigatonnes of water annually per following.
From: carbondiox...@googlegroups.com On Behalf Of Mike Williamson
Sent: August 25, 2023 12:15 PM
To: Tom Goreau <gor...@globalcoral.org>; Chris Vivian <chris....@btinternet.com>; 'Jim Baird' <jim....@gwmitigation.com>; rob...@rtulip.net; 'healthy-planet-action-coalition' <healthy-planet-...@googlegroups.com>; 'Planetary Restoration' <planetary-...@googlegroups.com>; 'via NOAC Meetings' <noac-m...@googlegroups.com>; 'Healthy Climate Alliance' <healthy-clim...@googlegroups.com>; 'Carbon Dioxide Removal' <carbondiox...@googlegroups.com>
Subject: Re: [CDR] HPAC meeting with Chris Vivian on Ocean CDR: August 24, 4:30 PM EDT.
The cooling benefits of bringing deep water to the surface may be offset by the release of carbon dioxide and methane as that water warms.
From: carbondiox...@googlegroups.com <carbondiox...@googlegroups.com> on behalf of Tom Goreau <gor...@globalcoral.org>
Sent: Friday, August 25, 2023 7:13 AM
To view this discussion on the web visit https://groups.google.com/d/msgid/CarbonDioxideRemoval/BY3PR13MB4994FA5085526911C707D313DDE3A%40BY3PR13MB4994.namprd13.prod.outlook.com.
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Jim Baird
The entire premise that we move 1m3~ton of seawater and replace it with cold water is wrong.
We move zero tons of water vertically but for the diffusion of water adjacent the heat engine condenser.
The thermohaline circulation is 15 Sv.
With TG the only vertical transfer of water is the 1 cm/day diffusion of warmed water from 1,000 m back to the surface.
The leading edge of a 1 GW TG plant is an area of 26,598 m2. So, with 31,000 plants the surface area of the ocean covered would be 824,538,000 m2 (824 km2). Or an area of about 28 km on a side, which would diffuse water at a rate of .000001 m/s (1/(60sec*60min*24hrs)) which is only 0.0008 Sv. Which is statistically zero disturbance of the thermohaline circulation, or the cold water resource. But a .02 C annual cooling of the tropical surface.
I have no expertise concerning the LW radiation but this is what Douglas MacMartin had to say about it in a conversation in which you were included a few months back.
There’s zero doubt about the sign of the effect; moving heat from surface ocean to deep ocean will reduce the outgoing LW from the climate, and in the long term, that would result in a net warming of the planet. And should be no surprise that if one cooled Earth surface by of order 1C (by any means), that the effect on TOA forcing should be a big fraction of current ~3 W/m2 GHG forcing (given that we are some reasonable fraction of the way to equilibrating that forcing). So that would independently get to something of order 2W/m2 effect, which is nontrivial. As Ye points out, the distinction here is whether one is cooling the surface by reduced SW (as in SRM) or simply by redistributing heat within the climate system without actually changing total energy content.
Whether or not that matters is another question… both the question of how long-term the long-term is (which I think your logic is correct though I’m not sure about the numbers); if one can push a problem out a few hundred years that’s a big deal, and also if one is generating energy used by humans and thus reducing CO2 emissions.
Broadly speaking my reaction is that it’s something to be aware of and not pretend away, but not a showstopper unless there’s a reason why your time constant numbers are way too long.
I am talking about cooling the surface by probably 1.8C over the course of 226 years and then the status quo over the next ~2700 years.
That is how may W/m2/year?
rob de laet
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Ye Tao
Hi Jim,
Whether the molecules get moved or not is irrelevant. I have not figured any energy expenditure in that process, which is secondary whether it is an investment or a gain for human needs.
The problem is that the required energy flux is exponential in
time, given the short timescale (months to years) over which
surface cooling benefit will decay.
Ye
Jim Baird
Hi Ye,
The surface cooling is 409 TW per year which is about 7 percent of the total 6 petawatts that are transferred to the poles annually.
Only 31 TW of this annual cooling is converted to work that is undertaken on land and therefore is effectively a cooling of the ocean.
The 378 TW that are shifted into the ocean are then available to produce another 31TW with and a shifting of another 347 TW back into the ocean.
I fail to see the cooling benefit decay?
Jim Baird
From: Roger Arnold
Sent: August 25, 2023 2:30 PM
To: Tom Goreau <gor...@globalcoral.org>
Cc: Mike Williamson <mi...@wassoc.com>; Chris Vivian <chris....@btinternet.com>; Jim Baird <jim....@gwmitigation.com>; rob...@rtulip.net; healthy-planet-action-coalition <healthy-planet-...@googlegroups.com>; Planetary Restoration <planetary-...@googlegroups.com>; via NOAC Meetings <noac-m...@googlegroups.com>; Healthy Climate Alliance <healthy-clim...@googlegroups.com>; Carbon Dioxide Removal <carbondiox...@googlegroups.com>
Subject: Re: [CDR] HPAC meeting with Chris Vivian on Ocean CDR: August 24, 4:30 PM EDT.
> No, because TG pumps heat downward with a working fluid, it does not pump surface water itself downward.
It's not obvious that using deep waters as a heat sink to cool surface waters -- i.e., heat exchange via heat pipes, as opposed to simple upwelling -- is actually a good approach. Yes, if one wants to exploit ocean thermal gradients for power generation, then the alternative of artificial upwelling is no good. And yes, deeper waters do have higher concentration of CO2; the heat pipe approach does avoid bringing those waters to the surface. HOWEVER, the name of the game we're pragmatically forced to play is CROI -- Cooling Return on (materials and monetary) Investment. And there, the issues are cloudy.
Straight OTEC for power generation has never been a commercial success; its low thermodynamic conversion efficiency and other factors guarantee that it will give a very low energy return on investment.
The thermodynamic efficiency of conventional of OTEC is less than 3%. For TG it is 7.6% meaning therefore you get 2.5 times the energy at for one third the cost.
Attached is pdf showing the costs etc.
Claiming added value for cooling of surface waters is unlikely to make a significant difference. Under the current socio-economic regime, there's no way to monetize the cooling of surface waters. And if the world socio-economic system were to award enough of a monetary value to surface water cooling to make TG pencil out, TG would immediately be undercut by artificial upwelling. Artificial upwelling would be a more cost-effective way to achieve surface water cooling.
As to the supposed problem of bringing waters with higher levels of CO2 to the surface, it's illusionary. The extra CO2 in deeper waters comes from respiration and aerobic decomposition of organic matter higher up in the photic zone. The extra CO2 is accompanied by higher levels of nutrients liberated by decomposition. When the deeper water upwells, it feeds the growth of phytoplankton that convert the extra CO2 back to biomass. There's no net transfer of CO2 from the ocean to the atmosphere. In fact, there's a marginal transfer in the other direction, from the higher solubility of CO2 in cooler waters and the higher loading of biomass that the recycled nutrients support.
As to the value of ocean surface water cooling, it's a matter of life or death to many corals and other marine organisms that can't survive in the hot tub environment that our tropical oceans are headed for. It's true, as Yao Te notes, that cooler surface waters will emit a lower flux of thermal IR. If that were all there were to it, It would indeed mean that the earth's radiation imbalance would be increased. However, cooler ocean surface waters also mean lower absolute humidity in the atmosphere above. That translates to lower resistance to upward radiative diffusion of thermal energy. That expresses itself as a cooler sky temperature from backscattering of outbound thermal radiation. It's unclear (at least to me) how the balance works out.
- Roger
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Jim Baird
The effective Black Body temperature of the Earth is −18.8 °C but its atmospheric equilibrium temperature with the atmosphere is about 15C. So how can shifting surface heat into deep water be problematic in terms of IR?
In our paper Negative-CO2-emissions ocean thermal energy conversion, Greg Rau and I showed that I gigawatt of TG power would consume and store (as dissolved mineral bicarbonate) approximately 5 × 106 tonnes CO2/yr. With 31000 plants this would be 155 gigatonnes of CO2/year. Since the there about 3200 gigatonnes of CO2 in the atmosphere this total inventory could be removed in 21 years, which would then presumably bring the Earth’s temperature down to -18.8C.
The point being shifting heat into deep water isn’t the problem.
From: carbondiox...@googlegroups.com On Behalf Of Roger Arnold
Sent: August 25, 2023 2:30 PM
To: Tom Goreau <gor...@globalcoral.org>
Cc: Mike Williamson <mi...@wassoc.com>; Chris Vivian <chris....@btinternet.com>; Jim Baird <jim....@gwmitigation.com>; rob...@rtulip.net; healthy-planet-action-coalition <healthy-planet-...@googlegroups.com>; Planetary Restoration <planetary-...@googlegroups.com>; via NOAC Meetings <noac-m...@googlegroups.com>; Healthy Climate Alliance <healthy-clim...@googlegroups.com>; Carbon Dioxide Removal <carbondiox...@googlegroups.com>
Subject: Re: [CDR] HPAC meeting with Chris Vivian on Ocean CDR: August 24, 4:30 PM EDT.
> No, because TG pumps heat downward with a working fluid, it does not pump surface water itself downward.
It's not obvious that using deep waters as a heat sink to cool surface waters -- i.e., heat exchange via heat pipes, as opposed to simple upwelling -- is actually a good approach. Yes, if one wants to exploit ocean thermal gradients for power generation, then the alternative of artificial upwelling is no good. And yes, deeper waters do have higher concentration of CO2; the heat pipe approach does avoid bringing those waters to the surface. HOWEVER, the name of the game we're pragmatically forced to play is CROI -- Cooling Return on (materials and monetary) Investment. And there, the issues are cloudy.
Straight OTEC for power generation has never been a commercial success; its low thermodynamic conversion efficiency and other factors guarantee that it will give a very low energy return on investment. Claiming added value for cooling of surface waters is unlikely to make a significant difference. Under the current socio-economic regime, there's no way to monetize the cooling of surface waters. And if the world socio-economic system were to award enough of a monetary value to surface water cooling to make TG pencil out, TG would immediately be undercut by artificial upwelling. Artificial upwelling would be a more cost-effective way to achieve surface water cooling.
As to the supposed problem of bringing waters with higher levels of CO2 to the surface, it's illusionary. The extra CO2 in deeper waters comes from respiration and aerobic decomposition of organic matter higher up in the photic zone. The extra CO2 is accompanied by higher levels of nutrients liberated by decomposition. When the deeper water upwells, it feeds the growth of phytoplankton that convert the extra CO2 back to biomass. There's no net transfer of CO2 from the ocean to the atmosphere. In fact, there's a marginal transfer in the other direction, from the higher solubility of CO2 in cooler waters and the higher loading of biomass that the recycled nutrients support.
As to the value of ocean surface water cooling, it's a matter of life or death to many corals and other marine organisms that can't survive in the hot tub environment that our tropical oceans are headed for. It's true, as Yao Te notes, that cooler surface waters will emit a lower flux of thermal IR. If that were all there were to it, It would indeed mean that the earth's radiation imbalance would be increased. However, cooler ocean surface waters also mean lower absolute humidity in the atmosphere above. That translates to lower resistance to upward radiative diffusion of thermal energy. That expresses itself as a cooler sky temperature from backscattering of outbound thermal radiation. It's unclear (at least to me) how the balance works out.
- Roger
On Fri, Aug 25, 2023 at 12:17 PM Tom Goreau <gor...@globalcoral.org> wrote:
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Ye Tao
Hi Jim,
Are you saying that reducing upwelling IR radiation from the surface has no impact on top of the atmosphere (TOA) net flux? The point is exactly that shifting heat into the bottom exacerbates TOA energy imbalance.
The other hurdle is that one would need to first develop
heatpipes 2-3 orders of magnitude more thermally conductive than
the state of the art to bring the concept closer towards material
scalability.
Ye
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Jim Baird
Hi Ye,
I am not saying there wouldn’t be some impact, I just don’t think it is a first order concern.
“A Heat pipe is considered a type of thermal superconductor. They possess an extra ordinary heat transfer capacity and rate. The effective thermal conductivity of a heat pipe is up to 90 times greater than the solid copper for the same size?”
I don’t understand what you mean about material scalability? I think I addressed this in my powerpoint. One of the biggest cost would be the heat exchangers. The oceans contains 47 minerals and metals dissolved in solution, some of which are already being harvested. Thermodynamic Geoengineering platforms harvesting surface heat to produce energy would pass millions of tonnes of water through their heat exchangers, which could be adapted to extract a portion of the 50 quadrillion tons of trace elements that are dissolved in solution in the ocean. For example, 31,000 one gigawatt Thermodynamic Geoengineering plants would, move 124,000,000 tonnes of water per second through their heat exchangers, which means the 1.45 quintillion short tons of water - the total mass of the ocean’s water- would be shifted to these heat exchangers in about 370 years. The concentration of magnesium, currently valued at between $12,000 to $15,000 per tonne, is 1,272 parts per million. About 3 times the concentration of carbon dioxide in the atmosphere, which it is notionally being contemplated should be removed from the atmosphere at a cost of about $100 per tonne. The method of precipitating magnesium from sea water has been know for over a century. And magnesium alloys reduce the weight of heat-removing elements like heat exchangers used for Thermodynamic Geoengineering by a third without losing its heat transferring properties. At 1272 parts per million of the 1.45 quintillion short tons of water in the ocean, the current cost of the metal would be reduced by several orders of magnitude when produced as an adjunct to Thermodynamic Geoengineering energy producing operations.
Calcium is the third most abundant element in the ocean. Tom Goreau produces BioRock from calcium and or magnesium that is 3 times stronger than conventional concrete and sequesters CO2. This material also would be used in abundance in TG platforms.
Jim
Ye Tao
Hi Jim,
If you propose this method only as a way to produce energy, not to rectify the climate, then I would let it go and turn a blind eye to your assertion that the negative impact on the Earth's Energy Imbalance (EEI) was not of first order concern.
Calculations for why 1) the process has no climate benefit and 2) that it cannot possibly be scaled to tackle the EEI were sent to the group yesterday. Please check your email inbox. In case you cannot find them, I will forward to you in private.
Best,
Ye
Tom Goreau
The Earth energy imbalance results from the sum of global GHG and albedo effects, but local heat is determined by local energy inputs and outputs.
Downwelling heat via TG cools the ocean surface directly, and any effects on GHG and albedo are secondary via temperature effects on gas solubility and on water vapor pressure.
This gives up to one ocean circulation time, 1500 years, to reduce GHGs to safe levels and carefully test albedo modification to make sure it doesn’t have unexpected side effects.
Ye Tao
Hi Tom,
Global energy imbalance is the sum of local energy budget. Albedo effect, for instance, is clearly additive. There are of-course location-dependent impact/efficacy for any albedo modification. The same can be said of any other method that alters the local energy imbalance.
For small scale operations of TG, as is the case for small scale application of MEER or white roofs, there is not much measurable global impact. But once you start to scale, global circulation impact will most certainly emerge, and feedbacks of all kinds will start to become operational.
Best,
Ye
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Jim Baird
Hi Ye,
We have a 250 year record of the global energy imbalance.
Why would walking this history backwards be problematic?
Ye Tao
Hi Jim,
I believe you are confusing the Earth's Energy Imbalance (EEI,
power) with total accumulated energy imbalance (time integral of
EEI). Pumping heat into the deep oceans would resulting an
increase in the magnitude of the EEI, meaning that the rate at
which accumulated energy imbalance changes increases((surplus
grows faster) . It is true that there would be both negative
(e.g. less GHG from less evaporation) and positive feedbacks (e.g.
less latent heat shedding), but the overall impact would have the
same sign as the primary action.
Ye
p.s. EEI is the sum of all flux terms with positive defined as
pointing down towards the surface of the planet.Outgoing IR is
thus negative. Reducing it leads to a smaller negative
contribution to the EEI, causing the latter to increase.
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Robert Chris
Ye, Jim
Could someone do a back of the envelope
calculation to work out how much energy would need to be moved
to the deep ocean to reduce surface temperature by, say, 1C.
And then consider what impact that would have on ocean
stratification and circulation. I assume that making the deep
ocean water warmer would reduce its density and therefore cause
it to rise towards the surface. Would that be sufficient to
undermine a meaningful part of the initial surface temperature
reduction? What other biotic impacts might it have?
If the surface is made cooler by moving heat into the deep ocean this will, as Ye has noted, reduce the IR available to escape at TOA and therefore increase the EEI which would increase global warming.
There seem to be some complex feedbacks
triggered by putting climatically significant amounts of surface
energy into the deep ocean. Has anyone modelled this in a
comprehensive manner because it would seem more than a little
perilous to look at individual fluxes without taking into
account their epiphenomenal impacts.
Robert
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Ye Tao
Hi Robert,
The one-time energy displacement is 400
zetajoules (4E23J).
Let's simplify the thinking process. Consider instead a process
so magical as to move the excess heat not to the depth of the
ocean, but to outer space. i.e. let's assume for a moment that
this magical process is able to reset the thermal state of the
planet with the push of a button. As the system resets, but with
all the anthropogenic forcings kept constant, the Earth would
experience the full impact of the total effective radiative
forcing, since we would have lost Planck cooling.
This is identical to the SAI termination shock situation. And we
know from James Hansen's earlier work how the system would
respond. We would be back to square one within 10 years, the
time for transient climate response to act. Proximating the heat
reuptake process as a linear function, the average heating power
comes out to 2 pW. This is roughly the power any process needs
to deliver to hold surface at a steady state similar to the
preindustrial.
Ye
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Robert Chris
Ye
Not sure where you get the 400ZJ from that
source but in any event, paraphrasing your comments, you seem to
be saying that any reduction in surface cooling from moving heat
to the deep ocean by OTEC or TG would be reversed within very
few years, not so much from that heat coming back to the surface
but from less surface heat escaping at TOA. Have I got that
right? If so, it would seem to kill off OTEC/TG as a climate
intervention, although there may provide other benefits.
Robert
Ye Tao
Hi Robert,
I read the number from the graph in the link. You interpreted
correctly; the extra heat will come from new sunlight-generated
heat that becomes less able to escape. OTEC/TG
is not a climate intervention. It may have some local benefit
at small scale but I don't see why it would be superior to
moving the water directly for applications such as saving coral
reefs.
Ye
Tom Goreau
Pumping deep water up will kill reefs, not save them, because if you upwell deep water cool enough to cool reefs by 1 C you’ll add enough nitrogen and phosphorus to cause harmful algae overgrowth that kills corals.
From:
healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com> on behalf of Ye Tao <t...@rowland.harvard.edu>
Date: Sunday, August 27, 2023 at 9:44 AM
To: Robert Chris <robert...@gmail.com>, healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com>
Subject: Re: [CDR] HPAC meeting with Chris Vivian on Ocean CDR: August 24, 4:30 PM EDT.
Hi Robert,
I read the number from the graph in the link. You interpreted correctly; the extra heat will come from new sunlight-generated heat that becomes less able to escape. OTEC/TG is not a climate intervention. It may have some local benefit at small scale but I don't see why it would be superior to moving the water directly for applications such as saving coral reefs.
Ye
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Robert Chris
Tom, I think the idea is to move the heat
down not the water up. The schematic designs I've seen all use
a 'working fluid' (i.e. a refrigerant) to move the heat.
Robert
Robert Chris
Ye, I still don't see where the 400ZJ comes
from on that graph. My original question was how much energy to
reduce global surface temperature by 1C. That isn't what that
graph is mapping. Also the y-axis only goes up to 250ZJ and the
red area, which I assume is the accumulated positive ocean heat
content (ignoring the earlier negative fluxes) is about 3,000ZJ.
Robert
Ye Tao
Good point. Great to have a multidisciplinary group.
Ye
Ye Tao
The graph is not showing flux. It is already integrated to Joules. The difference between 2020 and 1960 is 360(+/-10) ZJ. I added 40 to account for the 3 years since latest data point.
Energy to reduce by 1C is roughly this amount, slightly lower
since we are more like 1.5C now.
Ye
Robert Chris
OK, I got it. I was reading the vertical bars as the annual increase i.e. ZJ/yr (hence my reference to flux) rather than as the cumulative total. Just had a look at the source paper and it's all clear. Thanks.
Having, it seems disposed of OTEC/TG as a
climate intervention, my earlier questions still apply in
respect to its use as an energy source. I regard the marine
environment as a highly complex system and if we were start
extracting energy from it at anything like the same scale that
we have extracted energy from subterranean carboniferous
fossils, I would expect there to be significant environmental
perturbations that would soon accumulate to be no less of a
threat to ecosphere stability than global warming now is. We
really need to proceed cautiously here and always with a systems
view.
Robert
Jim Baird
Hi Ye,
Final thought and thanks for your input.
Surface ocean heat is a use it or lose it proposition.
Tropical heat transferred out of the OTEC energy producing region becomes anergy that can never again be transformed into work but will, within one season, move from the tropics to the poles where it will melt ice.
The total warming of the ocean is about 0.0024 degree Celsius/year or 0.02 per decade., or 0.02 per year for top 500 m or so. (Or about 0.2 per year for top 5 m or so). As a consequence, the thermal stratification of the ocean is increasing about .2 degrees every year.
This is where we are headed.
What better approach fills the energy needs of 10 billion while mitigating climate change?
Tom Goreau
Artificial upwelling as widely proposed for surface cooling via OTEC could kill coral reefs by eutrophication, but cooling with TG would not.
Robert Chris
Jim
Can you provide some sense of the size and
nature of the physical infrastructure that would be necessary to
provide, say, 100EJ/yr of OTEC energy, including some insight
into its maintenance burden given that much of it is going to be
in the open ocean. That's a bit less than 25% of current total
final consumption. That wouldn't be enough to 'fill the energy
needs of 10 billion' but it would be a significant contribution
and would give a clearer idea of the scaling implications.
The thrust of my question is simply to get some feeling for its
feasibility and the timescale over which it could be built.
Robert
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Jim Baird
Robert,
Currently there is at most about 1 megawatt of OTEC being produced. I calculated, that if we doubled this every year, in about 20 years we could be producing 1000 gigawatts or 1 terawatt.
My calculation, that I believe Ron Baiman of HPAC would vouch for, the cost of this terawatt of power would $2.9 trillion a year.
The life of these plants is about 30 years, but since the goal is to produce 31 terawatts, I assume they will last 31 years, So, in total in 50 years from now, we would have 31 terawatts annually and since the life of the plants is 31 years we will start recycling and replacing the original 1000 plants every years thereafter at the same cost or less because we then will be able to obtain materials directly from the ocean and will have 50 years of development experience in our back pocket.
My understanding is before Covid, the global shipbuilding builders, mainly China, South Korea and Japan, produced about 80 major vessels a year so we would have up this 12.5 times, which it seems to me is doable. For example, how does Britain’s current shipbuilding industry compared to how things where in its hay day?
Jim
Robert Chris
Hi Jim
I'd be interested to see how the $2.9
trillion a year is arrived at. However, I'm really more
concerned at this stage to get a handle on the nature of the
physical infrastructure that would be required in order to
assess its engineering feasibility. How many plants, of what
size, where would they be located and how managed and
maintained, how long would each take to come into service, how
much steel, cement and other materials would be required, what
infrastructure is need to bring the H2 to shore and then to
insert that into the terrestrial energy system? It's practical
questions like these that I'm want to get my head round. These
will also give us a better idea about OTEC H2 could compete with
other emerging energy sources.
Robert
Jim Baird
This diagrams shows how I see TG scaling from a 3 gram lab scaled model to 1 gigawatt platforms both hydrogen producers, that are about 25% more expensive, and electricity producing greenfileds that can electrifiy all of the hard to decarbonize industries.
TG is one of the qualified entries in the MUSK entries. Per this link http://gwmitigation.com/Videos/TG5minladderpiitch.m4v it is in two parts. The first as shown in the video, demonstrates how Thermodynamic Geoengineering in a closed system can produce energy from the thermally stratified ocean which in turn cools the ocean surface preventing the offgassiing of CO2 from ocean as it warms. The prototype could also test various working fluids, including carbon dioxide for ocean thermal energy conversion. The second part would be a 10 MW ocean going plant that would sequester 1400 tonnes of carbon, thus meeting the 1000 tonne objective of the XPRIZE.
The lab scale prototype is doable within a year with assistance but to date the project has found no backers. And now it is unlikely the 10 MW plant could be operational in time to win the XPRIZE which has an end in the first quarter of 2025. But the XPRIZE is just a stepping stone to the real prize, which is a sustainable world.
This is a dated breakdown of the cost of these plants with $2010/kW costs from the literature. TG plants are a third the cost of conventional OTEC and each doubling of the capacity of the plants reducing the unit cost by 22%.
The $2.9 trillion for greenfields plants was based on mid Covid costs for materials.
In our paper Negative-CO2-emissions ocean thermal energy conversion transportation we estimated the delivery cost (1000 km) of hydrogen was $0.07/kg. But Rau et al. in a 2013 paper estimated the capital, operational, and maintenance costs of energy for hydrogen was $0.20/kWhe, which is for what I get from the OTEC literature?
My breakdown of the bill of materials for TG is shown here Appendix A - Cost.xlsx but I want to impress on this group that this information is proprietary and when the financing allows I will be filing patent applications to replaced the ones I have lost over the last 13 years and the various improvements that have been developed over that span.
Regards,
Jim Baird
According to the IMF, globally, fossil fuel subsidies were $7 trillion or 7.1 percent of GDP in 2022, reflecting a $2 trillion increase since 2020 due to government support from surging energy prices.
This is 189% higher than the cost of TG producing hydrogen and 240% higher than the cost of TG electricity.
Tom Goreau
Interestingly only about a tenth are direct cash handouts to polluters, around 90% are indirect subsidies like tax exemptions and deductions.
Robert Chris
I think this focus on cost is unhelpful. From a systems perspective a more critical set of concerns revolve around the real world practicalities of building this new energy infrastructure from scratch and how doing so would impact other existing activities and systems. The current global energy infrastructure was built over a period of more than a century and its existence today creates a degree of resistance to change, not for any nefarious reason but simply because like a flywheel, it's whizzing round at speed and its natural momentum carries it forward. A discussion about a whole new infrastructure can't take place without simultaneous consideration about what happens to the existing one with all it long-established associated interrelations deeply entrenched throughout the economic and social fabric of global society. It is precisely because of all that systemic inertia that change on the scale now required is so challenging.
Taking Doug's calculations at face value, a way needs to be found to incorporate TG into a systems change programme that looks way beyond what's needed for TG and takes into account an orderly and low risk transition of all the multiple economic, social and political interrelations within the fossil fuel economy.
In short, no one is going to get excited
about a promised land of milk and honey unless they can see a
credible pathway to it.
The technology is central but so are any number of other elements of the system of which it is part. This is why we're in the fix we are, because managing this fiendish complexity is so bloody difficult!
Finally, just to round off another depressing message from me, we have to recognise that when you cut to the chase, this is all about power - not physical power, but political power. That power is in the hands of relatively few people and they are very good at holding onto it and keeping others from getting their hands on it. Scientists and engineers can have all the ideas they like but the only ones that'll go anywhere are the ones that those with political power decide in their narrow selfish wisdom have some merit. Having merit here is a simple concept that stems from the idea of Realism. A proposal has merit if it benefits some but only so long as those in power believe it benefits them more. If that condition were not there, their power would diminish and that's a no no. That's the world we live in. Very occasionally, the internal contradictions with the system undermine its capacity to adapt and then it becomes an accident waiting to happen - and sooner or later that accident always happens. But just like a great TV series, even when it all seems to have ended, magically there's always more to come. So no need to be downcast, everything happens for the best in this the best of all possible worlds (Voltaire), so cover your bets by not leaving it too late to start planning for after the deluge. TG may be a critical part of that new world.
The practical lesson here is that our message will not get
purchase unless we have a charismatic articulate young leader able
to straddle both sides of the argument, the science and
engineering, and the politics. Who in our realm is up for that?
Robert
Jim Baird
This is why I think the first acters will be those that are the most vulnerable to fossil fuel prices like the small island developing states and the areas of the asia pacific who have limited resources.
It is in their interest to take the first steps which then will leave the fossil fuel laggards in the dust.
Just saying.
Jim Baird
Another thought. In my opinion Brian Von Herzen, would be an excellent spokesman for the brave new world.
From: Jim Baird
Sent: August 29, 2023 6:29 PM
To: 'Robert Chris' <robert...@gmail.com>; 'Ye Tao' <t...@rowland.harvard.edu>; 'Tom Goreau' <gor...@globalcoral.org>; 'Roger Arnold' <silver...@gmail.com>
Cc: 'Mike Williamson' <mi...@wassoc.com>; 'Chris Vivian' <chris....@btinternet.com>; rob...@rtulip.net; 'healthy-planet-action-coalition' <healthy-planet-...@googlegroups.com>; 'Planetary Restoration' <planetary-...@googlegroups.com>; 'via NOAC Meetings' <noac-m...@googlegroups.com>; 'Healthy Climate Alliance' <healthy-clim...@googlegroups.com>
Subject: RE: [CDR] HPAC meeting with Chris Vivian on Ocean CDR: August 24, 4:30 PM EDT.
This is why I think the first acters will be those that are the most vulnerable to fossil fuel prices like the small island developing states and the areas of the asia pacific who have limited resources.
It is in their interest to take the first steps which then will leave the fossil fuel laggards in the dust.
Just saying.
Brian von Herzen
http://www.climatefoundation.org/
NASA modeling has determined that carbon levels above 350 ppm are incompatible with sustaining a planet similar to that on which civilization has developed and to which life on Earth is adapted (James Hansen). In April, 2023, the Keeling curve exceeded 422 ppm for the first time in recorded history.
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