Climate tipping points: real and present

The planet has changed. This is Iceland’s Skaftafellsjokull glacier in 1989 and 2020:

As reported in Al Jazeera, Christiana Figueres, one of the architects of the Paris Agreement, was stunned speechless when:

    She was told by leading climate scientist Johan Rockström, the director of the Potsdam Institute for Climate Impact Research, that we have already gone beyond some key tipping points. Losing the resilience of the planet was the nightmare that is keeping scientists awake at night, Rockström said.

He was referring to (1) the Arctic summer sea ice (2) West Antarctic glaciers, and (3) tropical coral reef systems.

Back in 2009 when Rockström worked at the Stockholm Resilience Centre he developed with Will Steffen and others the Planetary Boundaries concept, (see also my Climate emergency – ecological sustainability within planetary boundaries, and a safe climate).

When researchers did a systematic review in 2019, Rockström said he was personally shocked by how much the planet had deteriorated in 10 years.

David Spratt summed up the state of play in a talk RESET.21 | MATTERS OF FACTS: THE SCIENCE OF GETTING IT RIGHT ON CLIMATE with this slide:

The slides from Spratt’s talk which contain a mass of information are posted at Climate Code Red as Matters of fact that we ignore at our peril.

Spratt points out that reducing emissions by 5% annually would have no statistical effect on warming for more than two decades. Aerosols from burning fossil fuels, which provide around 0.5°C cooling, would only last 10 to 15 years in the atmosphere if we stopped emitting.

He points out that our current greenhouse gas levels imply a Pliocene climate of 3-5 million years ago, when we had temperatures of 2-4°C higher than pre-industrial and sea levels of 20 to 25 metres higher. Equilibrium would be achieved over centuries to millennia, but our current commitment could give us 2°C or more by the end on the century together with multi-metre sea level rise.

I was surprised to read that the US government already uses 2.5 metres as the upper bound of sea level rise this century, and the Pentagon uses 2 metres. Karl Braganza from the BOM says business as usual could see a tidal surge of 3.08 metres in Cairns this century.

James Hansen estimates that if we want to restore Arctic ice, then we should aim for 300 t0 320 ppm.

On fairness, Spratt does the sums going by the IPCC playbook for 2°C to find that because of our high per capita emissions we would use up our carbon budget by July 2025.

So the situation is dire, requiring maximum effort. Spratt thinks we should aim for zero emissions by 2030. Here are two slides from the end of his talk:

Rockström’s talk was part of a podcast series Outrage + Optimism hosted by Christiana Figueres, Tom Rivett-Carnac and Paul Dickinson. It’s not search-friendly, but it may be possible to find 86. The Scientific Case for The Race to Zero with Johan Rockström. In it he says that scientists should not spare people’s feeling, or worry about frightening them into inaction. People have the right to know the truth.

He says rapid climate action will certainly help. Effectively we should halve emissions every decade and hope it works.

Last November in Our beds are burning I went into tipping points in more detail, including an important article by Timothy Lenton, Johan Rockström, Owen Gaffney, Stefan Rahmstorf, Katherine Richardson, Will Steffen & Hans Joachim Schellnhuber Climate tipping points too risky to bet against.

That article was published in December 2019. If Figueres had seen it, Rockström’s news should have been no surprise.

The Lenton paper emphasises the interactive nature of the various tipping points, and a cascading process leading to a point where humans lose control. This cascading process may have already begun. However, this does not mean that humans lose all agency and should just prepare for the worst. There is hope.

Lenton et al think that three decades to reach zero emissions is about the quickest that can be achieved.

They also indicate that whatever we do matters. For example, current levels of GHG may give us 10 metres or more in sea level rise. If we stabilise at 1.5°C that may take 10,000 years, but if we allow the temperature to reach 2°C that time-frame may be shortened to 1,000 years. Moreover, the higher warming goes above 1°C the more likely we will get existentially threatening runaway heating beyond our control.

So we have reached the ‘age of consequences’. We already have dangerous climate change which is impinging on lived experience. Leaving aside bad weather (droughts, floods and storms, heat waves etc), chronic wildfires, and bleaching events on Great Barrier Reef, alarming news about the die-off and extinction of plants and animals and sea life, we are getting daily stories about the impact of sea level rise.

In Vietnam Ho Chi Min City, with a population of around 9 million, sits in a flat delta region where 40 to 45 per cent of the city is less than one metre above sea level. So we have Under siege by climate, man-made problems, a sinking Ho Chi Minh City fights to survive.

Sea levels are rising at 45mm per annum, about 50% above the global average. Furthermore, the city is sinking, in large part but not totally through groundwater extraction.

There is a proposal to build a 33 km sea wall, but apart from the cost:

    In South Korea, the 33-km Saemangeum sea dyke and land reclamation project has taken 30 years since construction began, cites Ky. The sea wall itself needed almost 20 years to construct.

Meanwhile there is an active business in raising buildings. Construction engineer Nguyen Van Cu whose specialty is raising homes raised a 6,000-tonne church a few years ago.

In Florida some homes could lose 15% in value this decade, a report finds 35% by mid-century. For further reading see McKinsey Global Institute Will mortgages and markets stay afloat in Florida? That report is part of McKinsey’s broader series Climate risk and response: Physical hazards and socioeconomic impacts.

Melting sea ice in the Arctic may seem far away, but Rockström says:

    We’ve passed the point of no return there, which is, as you know, affecting weather systems in the northern hemisphere with heat waves and droughts and forest fires. It is impacting the entire Gulf Stream, is even impacting the monsoon system that provides the rainfall for the Amazon rainforest. And it’s even causing warmer surface temperatures that accelerate the melting of the West Antarctic ice shelf.

If it’s affecting the monsoon, it is affecting us directly.

While the area of Arctic sea ice is in trend decline, the volume is collapsing rapidly:

    Since 1979, the ice volume has shrunk by 80% and in just the past decade the volume declined by 36% in the autumn and 9% in the winter.

It is time for our politicians to seriously engage with the science and decide what they must do.

Clearly, though, 1.5°C is neither safe nor stable. As such it is not a longer term resting point. Our only path to a sustainable and safe future lies in no more than 1°C, of warming. Spratt and Ian Dunlop say make that 0.5°C. Either way we need to think seriously about emissions drawdown, where there are debates to be had.

Is any politician talking about it?

See also Temperature pushes Great Barrier Reef to tipping point.

50 thoughts on “Climate tipping points: real and present”

  1. Brian: Some humans and other species will benefit by further warming of the planet. Others may benefit from cooling. The speed with which this happens may be relevant in some cases. Species that cannot move fast enough to neutralize the effect of climate change (or have reached the limit of possible movement) will face extinction without human interference.
    Our ability to deal with climate change will be diminished by growing population.”
    “Global human population growth amounts to around 83 million annually, or 1.1% per year. The global population has grown from 1 billion in 1800 to 7.8 billion in 2020. It is expected to keep growing, and estimates have put the total population at 8.6 billion by mid-2030, 9.8 billion by mid-2050 and 11.2 billion by 2100. ”
    The damage done by the growing human plague may turn out to be more important for the future of humans and other species than global warming.

  2. John, I wouldn’t put one ahead of the other. If the globe warms it will reduce its carrying capacity.

    Fom the Paul Hawken drawdown post:

      His top solution is educating girls and family planning. In combination they would see 1.1 billion fewer people on the planet come 2050, and will save more emissions than on- and offshore wind power combined. Together educating girls and family planning could reduce 120 gigatons of CO2-equivalent by 2050 — on- and offshore wind power combined would come in at 99 GT.

    Rockström has 5 transformational policies for a prosperous and sustainable world. His last two are:

      Fourth, a redistribution of wealth. What if we could [agree] that the richest 10 percent could not allow themselves to amass more than 40 percent, maximum, of national incomes — a drastic redistribution of wealth, reforming the ability of equity across regions?

      And finally, fifth, a radical increase in more education, health, access to work, contraception, investing largely in women across the world, allowing us to deliver on SDGs on gender, inequality, economics and urban development.

    Most who know about this stuff say we have the knowledge and technology to make a safe, sustainable planet where nature and homo sapiens can flourish.

    The trick is in first deciding where we want to go, and then the policies, cooperation and social/political/economic renewal to get there.

    There are arguments about the ideal human population for the planet which vary quite a bit. I think I read somewhere that the ideal temperature for biological diversity on the planet was cooler than the Holocene, but this would take into account the oceans, which I understand is where 99% of the living space is, and most of it is effectively desert.

  3. Brian: “John, I wouldn’t put one ahead of the other. If the globe warms it will reduce its carrying capacity.” That is why we need to reduce the human plague to a level that gives us room to move if necessary. AND , among your suggestions: “Fourth, a redistribution of wealth. What if we could [agree] that the richest 10 percent could not allow themselves to amass more than 40 percent, maximum, of national incomes — a drastic redistribution of wealth, reforming the ability of equity across regions?”
    My guess is that this would increase emissions as the purchasing power of those whose expenditure is limited by income increases.

  4. John, you could be right in your guess about emissions increasing.

    Don’t quote me, but there has been a lot of talk about the share of emissions stemming from the top 1%, and I think about 100 companies producing most of the world’s emissions. The other day I heard someone complaining about Bill Gates doing 93 trips in his private jet while lecturing the world about giving up air travel. I tried to fact check it, but Google wouldn’t take the question seriously.

    We led the way in turning back refugees coming by boat. The worry is that the rich will adjust to climate impacts, and the poor won’t be deemed worth saving. There are millions already being displaced, and this will become more problematic from now on.

  5. Science writer Graham Lawton has an article in the New Scientist Net zero has taken the world by storm in a rare climate win .

    He charts where the world was a year ago wrt to zero net emissions by 2050 and where it is now.

    A year ago it was marginally held and had a tenuous grip on the public mind.

    Now it is everywhere. He talks about ‘tipping point’ as a concept in climate science. Then:

      More recently, though, the tipping point concept has found a new application in climate science as a way to explain, and possibly engineer, social change. The way changes in attitude creep along at a glacial pace before suddenly bursting forth to take root across society is a classic tipping point. This process is useful because it moves ideas that were once on the fringes of mainstream opinion rapidly to the centre; ideas such as the need for deep economic and technological changes to avoid a real-life climate disaster movie.

      Whether by accident or design, we recently passed one such social tipping point. In narrow terms, it is the sudden, widespread embrace of net zero. In broader terms, it means final realisation from all levels of society that we must take radical action or face dire, possibly terminal, consequences.

    That’s progress.

  6. Thanks, bilb. Forward looking, but still short-term in terms of our baked in commitments to warming, sea level rise, tipping points, multi-centuries and such.

  7. That is my point, Brian. As far as Labor thinking goes it is “we’ll rethink health and education (again), and do complete rework of workers and LBGTQ rights, we’ll talk about the economy and do another grant scheme for first home buyers,… and then we’ll begin negotiations on a carbon pricing mechanism.

    NO. Doing those things these 20 years later is pointless as the economy will collapse from a crescendo of Climate Callamities.

    Australia has to be a global partner as a resource for an urgently installed global solution at this stage, but Australia doesn’t have politicians with anything like the vision Europe is demonstrating. Denmark is making its wind resource available to the entire European Union, under its management.

    What would such a plan look like for Australia?

    The Australia Government can barely manage a country picnic, though it seems like Twiggy Forest might be able to.

  8. Bilb: The ACT’s Labor/Green alliance government has driven the ACT to “100% renewable electricity” This figure is calculated on the basis of renewables produced in Canberra and renewables produced by ACT owned renewable power plants outside of the ACT. The investment has been driven by renewable energy auctions, not a price on carbon. (These auctions are a common feature in many countries.)
    Somehow federal politicians seem to be able to fly in and out of Canberra without ever bothering how a long lived Greens/Labor alliance can acheive these things.

  9. John, I’m not arguing the merits of the case, and I’ll try to dig up links later, but three points.

    First, there is a price on carbon in the EU which is being traded, from memory at US$46 per tonne, and Biden is setting a price also to be used in US government planning called SCC (the social cost of carbon) which I believe is to be US $42.

    Our companies will have to expect to pay border taxes for exports into those areas in the future unless we conform with credible plans to reach zero by 2050, which is fast becoming the international norm.

    Second, we have since the Gillard days a Commonwealth Government’s Emissions-Intensive and Trade-Exposed (EITE) scheme where carbon credits are bought and sold. There was an article recently in the AFR saying some firms are buying up credits they don’t need now, but will expect to pay more for later on.

    Third, when state governments use reverse tenders to commission power generation the state is deciding what power generation is built, and to some extent where. Now in NSW we have the Commonwealth also doing the same thing through the UNMI (Underwriting New Generation Investments), through harrassing AGL about Liddell, and intervening directly through Snowy Hydro as a Commonwealth owned generator.

    That’s at least for the NEM (National Electricity Market) in the eastern states.

    My preference would be for the states to be in charge of generation and transmission, with coordination of operation and planning already set up through AEMO, AEC, AER, co-ordinated by the ESB (Energy Security Board), which was answerable to the COAG Energy Council, meaning the state energy ministers, chaired and supported by the federal minister, within the framework of a national energy policy.

    Reverse auctions would work well in this situation.

    Now we have no national energy policy, COAG Energy Council has been replace by a National Cabinet subcommittee, chaired by Angus Taylor who apparently tells no-one what he is really up to, and if he did you would be a fool to believe him.

    AEMO has done an Integrated System Plan:

      that provides an integrated roadmap for the efficient development of the National Electricity Market (NEM) over the next 20 years and beyond.

    It seems that Angus Taylor is doing his own plan.

    Now we have Energy Security Board chair Kerry Schott warns against state energy intervention and saying Time for decisive action as the NEM is “no longer fit for purpose”.

    Actually Kerry Schott believes the ESB planning can be responded to by market operators, and that there is no need for governments to intervene at all even with coal’s rapid decline.

    That’s arguable, but I think the states are going to act. What we don’t need is Angus Taylor and the states butting heads.

  10. JohnD, while the ACT’s achievement is excellent, the ACT is just 2% of Australia’s population. South Australia is a better achievement example.

    Let me point out thought that you brought up the prospect of powering the world’s shipping with renewable ammonia fuel in order to avoid using Nuclear energy for that role. I demonstrated that in order to achieve your ambition for renewables it would require new renewables capacity over 400 times greater than the capacity Australia has achieved over the last 15 years.

    That Canberra has done a good job for their local inhabitants is irrelevant in the global CO2 emissions challenge.

    While Australia does have the insolation to solve much of the world’s energy needs, it totally fails to achieve a determination to do so due largely to its wildly vacillating political ideologies and political participants.

    From a global perspective Australian’s attitude to their solar resource is as bad as an authoritarian leader who refuses to use the enormous wealth of the treasury to relieve the starvation of that country’s people.

  11. Sounds a fair assessment to me, bilb. BTW, SA is not much bigger than Tasmania in its grid electricity usage.

    Apart from the brief Rudd/Gillard years Australia has been a rogue state on climate since the Kyoto protocol in 1997.

  12. Bilb: “JohnD, while the ACT’s achievement is excellent, the ACT is just 2% of Australia’s population.” This doesn’t mean that others couldn’t learn from what they did. Renewable energy auctions are widely used these days. The ACT was one of the leaders.
    Brian: “First, there is a price on carbon in the EU which is being traded, from memory at US$46 per tonne, and Biden is setting a price also to be used in US government planning called SCC (the social cost of carbon) which I believe is to be US $42.” This doesn’t mean that it isn’t a relatively inefficient way of driving climate action.

  13. JohnD,

    Putting a price on Carbon on its own will not resolve the CO2 emissions Global Warming problem. What will solve the emissions problem is utilizing the cash accruals from the Carbon Price to fund and build alternative energy solutions.

    The Carbon Price on its own is only a marginal deterrent to the use of Fossil Fuel simply because they represent a marginal component of most peoples weekly budget. A good case to study is the cost of cigarettes and people’s persistence with the product despite a twenty fold increase in the price of the item.

    People will only structurally change their behavior when there is a substantially better alternative readily available.

  14. BilB

    What will solve the emissions problem is utilizing the cash accruals from the Carbon Price to fund and build alternative energy solutions.

    Yep, but that won’t happen. A prime example is the US “Covid Relief Bill “ that only a tiny fraction is directed at covid relief.

    I would support a modest carbon tax if a redirection of 20% of established scientific research funds went directly toward alternative energy solutions along with it.

    Surly they wouldn’t complain if it’s to fix the greatest threat to mankind.

  15. Good on you Jumpy.

    You do realise that the heroes of what’s you are calling for are Jimmy Carter who kicked of and drove wind energy research and Barak Obama who supercharged battery research. George Bush deserves a mention for his ethanol production support.

  16. Bilb; “Putting a price on Carbon on its own will not resolve the CO2 emissions Global Warming problem. What will solve the emissions problem is utilizing the cash accruals from the Carbon Price to fund and build alternative energy solutions.” I have no problem adding a carbon tax to our tax mix but it is not a price effective way of driving climate action.
    Somehow we seem to be surging ahead with climate action without a carbon tax. In terms of providing a stable renewable energy system it makes more sense to use auctions or the competitive tender system that the construction industry has been using for yonks to control what is built where.
    If you must trade, offset credit trading has the advantage of controlling average emissions. (It is the logical way to drive down vehicle emissions.)

  17. OK, JohnD. Again you have completely ignored the issues raised and carry on with fixed notions. You are completely oblivious to the scale of the situation and refuse to challenge your own views quantitatively. However sincere your intentions, your hand waving use of fanciful solutions and failure to explore a field of solutions puts you in the same tent as the LNP, and are therefore irrelevant to the broad discussion.

  18. To crudely quantify how far Australia has progressed towards energy sustainability over the last 15 years, the factor is one sixth of the way.

    Every Australian uses 7 kW of fossil fuel energy continuously. This figure is Australia’s total electrical equivalent fossil fuel consumption times the population. An easy figure to verify. As we are comparing that to the electrical equivalent we will assume an electrical equivalent efficiency of 25%, so divide by 4.

    So far Australia’s total installed solar capacity is 13 gigawatts which we divide by 2 (day and night and windy or not). So 7 gigawatts or 7 million kW capacity times 24/365 is 61.3 billion kWhrs versus 368 billion kWhrs of electrical equivalent fossil fuel consumption. Fossil 368 versus Solar 61. Hmmm.

    I don’t call that “surging ahead”, I call that a “Must try much harder” result.

    Energy auctions are not going to save us.

    The essential point is that this is before you consider Australia’s responsibility to the world, Australia being such a significant solar collecting land mass, matched only by the Sahara Desert, and perhaps the California Desert areas.

  19. Bilb: “Energy auctions are not going to save us.”
    They have been the tool that got the ACT to 100%.
    “Renewable energy auctions are an increasingly popular tool for governments to procure renewable electricity at moderate cost. IRENA’s report, Renewable Energy Auctions in Developing Countries, describes various types and aspects of renewable energy auction schemes, drawing on the actual experiences of five countries: Brazil, China, Morocco, Peru and South Africa.
    In well-designed auction schemes, the competitive bidding allows unbiased “price discovery” by the authorities, resulting in greater cost efficiency for electricity from renewable sources, IRENA’s policy team found. Auctions can also include local content requirements to ensure the development of industries and creation of jobs in the renewable energy sector.
    Not all auctions work the same way, and different methods offer varying degrees of complexity, speed and transparency. Streamlined administrative procedures, fairness to all bidders and transparency are essential to the success of an auction scheme, the report adds. ”
    (I got 104 million hits when I googled “What countries use renewable energy auctions.” Renewable energy auctions are not just a JD brain burst.)
    Renewable energy auctions are essentially the same as the competitive tendering that is the bread and butter of the large scale construction, contracting and mining industries I spent most of my working life in.
    The trouble with put a price on is that nothing happens until the price is high enough to justify action. Even then many people will find that it costs less to do nothing and put up with paying the increased price.

  20. JohnD, I am not arguing against Auctions. Auctions are great if they get the projects moving. Nails are great too, but nails are not the answer to “We need a new City next year”.

    To the reality “We need 400 times our existing Renewable energy installed capacity” the answer is not “Auctions”. Auctions may be part of the answer, they are not where this discussion or process starts, at all.

    Shallow focus will be the death of Australia as we know it. The LNP have been successful at narrowing the focus then beating down the scale of the solutions considered to the point of irrelevance.

    Labor need to broaden the argument to engage solutions for the world, not just one small part of our local problem.

    Look at Twiggy Forest’s approach. He had an idea then he walked it round the world to come back and make the bold statement then (presumably) got on with the planning and the project.

  21. Interesting comments, bilb

    I keep an eye on Nem Watch, so I’m under no illusions as to how much coal we are burning. Not so much gas as we used to.

    I think the ACT is folded into NSW, and SA is not big, and often imports power. Qld, Victoria and Tasmania consistently over-produce, but only Tasmania is pure.

    John, I’m not here arguing the merits of carbon taxes, or of reverse auctions, but it seems likely that everyone will use both sooner or later. The backbone of the NEM is coal, which is mostly going broke, so the system will need to be rebuilt.

    You’ve probably seen Quiggin’s piece No point complaining about it, Australia will face carbon levies unless it changes course at RenewEconomy or The Conversation.

    There are people who argue for carbon pricing as a main strategy, but I’m not sure any country puts all their eggs in that basket.

  22. Brian: If most of Australia’s major customers carbon tax countries intend to charge a carbon tax on imports from companies that use some other method to drive climate action it will probably make sense to charge a carbon tax and either use the income from this tax to do things that need doing or reduce other taxes. The fact that this is being forced by countries that want to use carbon taxes doesn’t necessarily make it good policy. The bottom line should be how fast a country is driving down its fossil carbon emissions, not how this is being driven.
    As an engineer/operation manager I took the effort to understand the detailed cashflows of the plants I worked in. Helped a lot with decision making. I also had a lot to do with technical issues in the plants where I worked as well as design, commissioning and economic evaluation when I moved to the construction industry.
    I see things like the production of clean electricity as an engineering problem because the system has to be managed to maintain voltage, phase and frequency in an environment where both demand and capacity can change rapidly.
    Unfortunately the marketers have been allow to take over and and drive the system using a crude system based varying output based on spot prices. (“Markets are the answer: What was the question.)
    We need contracts based on availability where central controllers manage demand and output to avoid disruptions. It is about management and engineering, not economics and marketing.

  23. John, I have no disagreement with your last comment in so far as it applies to the management of the electricity system. Before we became possessed with privatisation and competition, dating from the end days of the Keating regime we had some of the cheapest electricity in the OECD, and the lights stayed by and large, apart from storm and tempest etc.

    We are still infected by the privatisation and competition ideology, with the added complication of global warming fact and fossil fuel fixation and lobbying, which makes it difficult to get agreement on a way forward.

  24. “ We loved this sunburnt country,
    This land of sweeping plains,
    With its ragged mountain ranges,
    Just not droughts and flooding rains.
    So we left the far horizons,
    And moved to beaches and the sea,
    The beauty and the terror
    Was way too much for a
    Family of three and Me!

    As decades passed
    World changes vast
    New dangers to endure
    Sun, sweeping plains and flooding rains
    Others came, great wealth the allure
    Vast Solar fields, Canals and energy yields
    “Our” land transformed, World saved to be
    All out of sight and out of mind
    We gave it up for free”

    Just as the rush for Gold became the purpose for being in this barren land of “ours”, Solar energy is the new, but perpetually replenished, wealth resource of this massive and largely barren land. The notion that we can keep it to ourselves while not utilizing it at a time of great need, is totally Trumpean.

  25. Interesting bilb.

    So I guess it depends on where you live. Where I live I think the dominant use of electricity is in cooling.

  26. 1. Every body uses hot water to a greater or lesser degree. This reflect the number PVT’s you install in your system. The PVT’s that I have been talking about for years now (it always amazes me how little people take in) use oil circulated through the panels and circulated directly to the water cylinder. This eliminates the problem of steam formation on hot days with no circulation.

    2. Solar airconditioning is possible in a two stage system. It requires a temperature above 110C for an effective Ammonia or Lithium Bromide evaporative chiller system to solar cool your house. This can be achieved using the PVT as a preheated and a separate heat only panel to boost the temperature to above the 110C, again using a small circulation pump and oil to transport the heat around.

  27. bilb, thanks. If I can’t carry a lot of technical stuff in my head. Never could. If I could I would have ended up with a different life, probably.

  28. Brian, not you specifically, it is all of the other people including industry players, the government, and the public at large. I have trouble understanding how increasing energy efficiency from 20% to 80% isn’t instantly attractive. I know full well though that part of the reason is that the grid energy industry have cleverly manipulated domestic solar into a position where they command all of price, returns and usability. The whole thing is a scandal with government incompetence being the pivotal enabler.

    The fact is that households do not benefit from their rooftop solar.

    The systems are set up so that all of the rooftop solar is sold to the grid at 6 cents per unit, and people buy all of the electricity they use at the retail rate. You cannot benefit from the electricity that you produce at the retail offset rate as you should be able to because you do not have the correct inverter or system to make that possible.

    For the time being this is a minor problem. As batteries become more accessible the situation will change.

    The hot water part of the system is the best improvement to be made. For both energy production and energy storage. Charging a 200 liter water cylinder requires around 10 kWhrs of electricity which at off peak rates is a cost of just 50 cents to two dollars a day.

  29. bilb it is hard to imagine why an idea like that would not be taken up.

    On a personal level, we are probably not going to be in this house long enough to make significant investments. The real estate guy we consulted said whoever owned it next would spend half a million to make it into a 5-bedroom house. The front has to be retained because it’s pre-1946.

    He thought the swimming pool had value, but the solar panels, zip.

  30. Bilb2: “Solar airconditioning is possible in a two stage system. It requires a temperature above 110C for an effective Ammonia or Lithium Bromide evaporative chiller system to solar cool your house. This can be achieved using the PVT as a preheated and a separate heat only panel to boost the temperature to above the 110C, again using a small circulation pump and oil to transport the heat around.”
    40 yrs ago AMIR, the no for profit I worked for supported a cooperative review of air conditioning options for hot mining towns. Can’t remember the details but the sort of thing you are talking about was not competitive.
    If you are interested in reducing the cost of cooling and heating it is worth thinking about the use of phase change materials to store heat or cold. Phase change materials allow the generation of heat or cold to be done off peak (Cheap power) or when the ambient temperature is low (cooling) or hot. (Heating) In many parts of Australia the daily temp range is often enough to allow heat or cold to be stored without the need for heat pumping. For background information see:
    For my ReviewEconomy article on the subject see:

  31. I think that you are confused, JohnD, which means that you did not understand the substance of my comment. Neither of your linked articles talk about utilizing heat to create cold.

    As to the economics of absorptive chillers I invite you to consider the information here in.

    You should notice that the equipment in this 2017 (4 years ago not 40 years ago) article covers industry scale commercially available chillers used today throughout cities to cool buildings, and used for their economics.

    The main advantage of using ammonia chillers over Lithium Bromide is that Ammonia can chill to -30C whereas Lithium Bromide cannot. This means that the Ammonia Absorptive system can utilize heat above 110C to freeze water (phase change) for later (off peak) cooling of buildings utilizing both phase change and thermal mass in various ways for best effect.

    The ammonia system is not new. Look up the famous Australian Icey Ball fridge. Most old fogies like us will remember the kerosene fridge, and the more modern gas heat powered fridges in caravans, etc.

    I suspect that the AMIR review you are talking about was comparing absorptive chillers of the time to fossil fuel powered compressor chillers. However it is certain that in the intervening 40 years technologies have developed and improved in many fields.

    We are all working on the same team so please lets not beat each other up for egotistical information dominance. Lets try to combine our information, grow our technologies and discuss the benefits to achieve more advanced solutions.

  32. When I was considering ways to make low cost housing for outback and aboriginal communities I was looking at the potential for non moving part Quonset hut style roofing panels that utilized concentrated heat on their upper surface to produce cold air on their lower surface utilizing molded in ammonia absorptive chillers. I’m pretty sure this is workable, it just comes down to people wanting for their to be solutions rather than assuming things are impossible.

    One thing Google has proven is that the more and better questions one asks, the more and better answers there are to be found.

  33. Bilb: I need some hard figures comparing the absorbtion cooling processes you are talking about with alternatives. Keep in mind that absorbtion cooling works by applying the heat at the bottom of the system so I am not quite sure how you intend to use heat falling on the roof.
    Traditional buildings in places like the middle east are built to have high thermal inertia with people sleeping on roofs at night to take advantage of the large differences between day and night temperatures. Clothing was often about protecting the body from direct sunlight. Phase change materials provide a mechanism for storing heat or cold in a limited amount of space while avoiding the need for thick walls.
    By contrast, warm moist environments encourage the use of low thermal inertia that allows buildings to cool quickly after sunset. (Think traditional Qld house.) Minimal/zero clothing is more common than it is for hot dry because it allows the breeze to cool the body.)
    I have lived for years in both environments.
    The hot dry was very hot. I worked and walked outside all year round. Kidneys adjust.

  34. It is all spelt out here ……. ,JohnD.

    You should be noticing that this is actually a phase change machine with the additional feature that the energy on the cold side can be organized to be collected and stored remotely from the mechanism. On the hot side heat can be transported with an additional phase change process called heat piping.

    You are demanding, Jumpystyle, hard figures delivered to you so you don’t have to think? As with everywhere engine efficiency is a variable highly dependent on the available heat gradient, and the particular thermo chemical process.

    Absorptive chillers are usually a co generation energy component used to convert otherwise waste heat to useable level ie heat to cold or low grade heat to a higher grade or a combination of both.

    If sufficient electrical energy is available then the compressor chiller system is more efficient by 4 to 7 times, however where large surface areas are being baked in solar radiation the absorptive chiller has the advantage of have no moving parts and requiring no maintenance.

    Domestic solar airconditioning systems are used in Italy

  35. Bilb: “You are demanding, Jumpystyle, hard figures delivered to you so you don’t have to think? As with everywhere engine efficiency is a variable highly dependent on the available heat gradient, and the particular thermo chemical process.”
    A serious insult on this blog but, yep, I didn’t really want to spend the time finding comparative data.
    I knew from my childhood that absorptive systems work for refrigeration but ended up not competing with compressor style heat pumps.
    I also know from the AMIRA study that I was familiar with that bromide based absorptive air conditioning was not found to be cost competitive with heat pump based systems in the Pilbara.
    This doesn’t mean that absorptive systems won’t compete under some circumstances .
    The phase change materials I talk about could be thought of as “ice with a different melting point to that of water.” Their inclusion in cooling or heating systems can save power cost by doing the heating/cooling at times of the day when electricity is cheap and/or reducing the power needed by doing the cooling/heating when ambient temperature is close to target temperature. (In some places where ambient temperature gets below target cooling temp at some times of the day there may be no need for heat pumping at times.)
    Try googling “Use of phase change materials in Australia” for more information.
    Asked a similar question for absorptive cooling. Got the following comment in one of the links I followed up:
    “The main market barriers for solar cooling in Australia have
    been identified as: [7, 8]
    – Low electricity prices
    – Low-cost conventional air conditioning
    – Cross-subsidy of conventional air conditioning system by
    all electricity customers who have to pay for network and
    generation infrastructure
    – Most components manufactured overseas and imported
    – Low number of installed systems
    – System complexity
    – Professionals involved lack training and experience with solar
    – Australia’s large climatic variety makes it difficult for a
    standardised solar cooling system to be implemented.
    There are no major unsolvable technical issues for the
    implementation of solar cooling. The main barrier for
    implementation is economic, not technical. There are sufficient
    installations in Europe where the technology has been proven
    feasible but the low electricity cost and cheap conventional AC
    units in Australia make competition difficult. Nevertheless,
    economics for solar cooling can become much more favorable
    for a range of building applications and locations with higher
    electricity cost, such as islands, remote locations and off-grid
    It is not all about these ignorant Australians rejecting this amazing technology.

  36. That is a better appreciation of the Solar Air Conditioning JohnD, but you lost track of the original point that I was making and in “it is not all about these ignorant Australians rejecting this amazing technology” you amplify this.

    I was pointing out that those ignorant Australians are rejecting this amazing energy opportunity in continuing to heat water electrically. This point will only become evident when Twiggy Forrest calls for all of the available off peak energy for his hydrogen for steel production and the grid operators say “but we have contracts to use this energy for heating water”.

    The fact is that heating water from grid electricity is just plain stupid when a huge percentage of houses have hardware on their roofs that should be filling that role and becoming more efficient in the process. We are talking about raising the efficiency of solar panels from 21% to 80% efficient.

    To go one step further is that energy utilization gap that makes solar airconditioning via absorptive chillers worthwhile considering. For a roof with 4kW electrical capacity there is a further 12kW of available energy going to waste. 4kW of that wasted energy should be heating water, but the further 8kW could be, however inefficiently, cooling absorptive. And that is before you consider the possibility of a hybrid absorptive solution including a compressor in system.

    The country with the most to gain from solar energy is doing the least to take advantage. Why? Because they are lazy on the one hand, and have minimal production capacity or knowledge on the other, not to also nation that they are intellectually blocked by an automatic presumption of inability and failure.

    Does that sound harsh? I hope so, because it is all unnecessarily true.

  37. Bilb: Australians have been using solar hot water heating for yonks. The heating comes direct from the sun with no conversion to electricity in the middle. See for example

    Some people in Australia are investigating absorptive building systems and claim that these systems will be competitive in some cases.
    It is worth noting that most people buy reverse cycle air-conditioning because they want heating during the winter as well as cooling during the summer.
    I think your dump on Australians is a wee bit extreme.

  38. Facts and figures, JohnD.

    “Despite an excellent solar resource, the penetration of solar water heaters in the Australian domestic market is only about 4% or 5%, with new dwellings accounting for most sales.”

    Had Solar PVT’s been an essential component required by government this 5% solar water component would have been nearer to 23%.

    Looking at the incentives for installing solar water heating the full cost of the water heating system I designed would be covered by that amount when installed with a solar PVT system.

    Back to you, JohnD. Tell me again how Australia is an energetic user of solar for water heating.

  39. Bilb: We had solar hot water in the Pilbara (Power source diesel generators) and solar panels in Brisbane. Did the sums in B’bane and decided that the panels were a more cost effective way of reducing carbon emissions. The power used for hot water was off-peak.

  40. That is the calculation every one does, JohnD, and the outcome is the same because that is what the government at the time wanted. However if 6 of your 16 solar panel set cost an extra $200 and that provided most of your hot water then the calculation would be very different.

    The system I designed requires no header tank on the roof and there is no visible evidence of its existence other than several small tubes leading from the roof installation to the water cylinder, wherever that is placed in the house.

    This system circulates oil through very thin flat tubes that are bonded to the back of the glass panel of the solar cells. The oil is circulated via a very small 60 watt pump powered by the solar panels to a vertical heat exchanger standing beside the water cylinder. Oil circulates down through the heat exchanger and water thermo syphons up. The heat exchanger is just an externally insulated 40mm diameter stainless steel pipe with several smaller tubes inside top to bottom to circulate the hot oil.

    When the water cylinder is fully charged the oil pump stops and the whole system is safe to just sit till it is required to circulate again.

    The only negative with this system is that there is a small amount of potentially flammable oil on the roof of the house, but this is quite small and there are non flammable oils for high risk situations. But the real advantage is that there is no requirement to allow for the boiling of water in the system and all of the problems that creates.

    The positive of this system is that it turns the household water cylinder into a solar energy battery of 10 to 20 kW capacity, it improves the efficiency of the solar PV panels it is attached to, and it reduces the size of the required installed capacity of residual fossil fuel grid energy system by as much as a third.

    Why is this system not available?

    Because our government and the solar energy industry don’t know how to ask the question “if we wanted to make rooftop solar 2 to 3 times more effective with out consuming more material how would we go about it?”

    Once I have my whole energy system installed on my boat I will look at converting 2 of the Panasonic panels to include the thermal function, which would give me about 1kW of thermal capacity for my energy system and minimize to near zero the amount of diesel I use for heating.

    For interest the special minimum profile Stainless Steel heat collection tubes are made in the Czech Republic for VW.

    So that choice you made however long ago was probably the right choice for time as your off peak electricity bill is probably only $350 per year, but in CO2 emissions it means 3.83 tones of CO2 released every year
    ( )
    , and would take 4 years to save the $1200 extra cost of the PVT’s. But over the course of the next 20 years it means a loss of $5600, which as a saving would be enough to pay for your funeral.

    NB: 3.83 tonnes of CO2 (heating 300 Litres per day) as emissions over 20 years makes about 77 tonnes, the probable weight of your whole house.

  41. It is of no interest to me JohnD, other than it being a lost opportunity which you should appreciate as keenly as I do.

    Your lack of interest, though, tells me you fail to understand it.

    By the way did you discover with eutectic energy storage that the substance with the highest phase change energy storage capacity is actually water?

    My interests going forward involve improving anchoring systems for boats, developing a system to properly protect my electronics and boat energy system from lightning strikes (at least as best as possible), managing waste when at sea, experimenting with a device to alleviate sea sickness when below decks, and learning how to make alcohol using driftwood as an energy source.

    Humans are incapable of saving themselves. Just as in the movie Forbidden Planet the enemy were “monsters of the Id” who could draw on the immense energy system developed by the Krell, the real enemy to us in our time preventing progress is simply Ego. Ego driven greed, which we have recently learned can draw on the immense negative capacity of miss information and stupidity. The power of the big lie over science.

  42. Bilb2: “By the way did you discover with eutectic energy storage that the substance with the highest phase change energy storage capacity is actually water?” Yes and cheap too.
    However, the key thing of interest is the phase change temperature. For example, if you want to keep a house cool you might use a phase change material that melts at say 25 deg C to store cold that is produced when the cost or production is low. (Maybe off peak at night.) In many parts of Australia this might be done at night without having to run anything.

  43. The exact temperature doesn’t matter, what does is the thermal mass or thermal ballast. You control the temperature with the energy draw rate. The fact that your ballast is subzero and you are drawing off the latent heat of liquefaction mixing the colder air slowly with room air for comfort just gives your system greater endurance. That is the advantage of the Ammonia cycle in a passive or even hybrid solar system, it gives much lower temperatures. Having said that I really like this version .

    For interest one visible use of eutechtic salts for cooling was the Peters Ice Cream mobile vending carts which were made in Portugal. These had something like a 17 hour subzero endurance after a 24 hour charge period.

    You might be interested in what the CSIRO are doing in this field. Google CSIRO solar house for a browse.

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