1. OCAU Merchandise is available! Check out our 20th Anniversary Mugs, Classic Logo Shirts and much more! Discussion in this thread.
    Dismiss Notice

Consolidated Climate Change/CO2/Global Warming Thread

Discussion in 'Science' started by hlokk, Feb 12, 2007.

  1. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    To determine how long anything will last "accelerated aging testing" is used. For that to be effective though you need to know what will cause the damage / degradation.

    From the little I know the actual PV cells should last a very long time with a gradual degradation in efficiency as the article says. Then there's the problem of their housing and interconnections. I've seen reports of some having issues within a few years but that's because of improper curing of some polymer inside the housing causing acetic acid to be released.

    The housing and interconnections are probably the biggest concern and that depends on the environment. I'm on the sidelines of a largish remote install close to the ocean. The suppliers want us to use marine grade panels because of the salt. The housing for these is fibreglass but I'm not very confident about how well that will hold up under the UV load. I'd prefer they used marine grade stainless but that's expensive.
     
  2. adamsleath

    adamsleath Member

    Joined:
    Oct 17, 2006
    Messages:
    20,314
    Location:
    Sunnybank Q 4109
    did australian coal fired stations bother to put in scrubbers to take out so2 and toxins like that?

    seems like coal power in aus has gotten away with being one of the dumbest and dirtiest in the world. eg hazelwood perhaps they should receive a special award just for that.
     
  3. power

    power Member

    Joined:
    Apr 20, 2002
    Messages:
    68,300
    Location:
    brisbane
    Oh dude we have clean coal, no scrubbing necessary.
     
  4. adamsleath

    adamsleath Member

    Joined:
    Oct 17, 2006
    Messages:
    20,314
    Location:
    Sunnybank Q 4109
    Last edited: Jul 31, 2016
  5. dr_deathy

    dr_deathy Member

    Joined:
    Apr 27, 2007
    Messages:
    2,962
    Most large scale installs will not be near the coast and anything is like that. Lets not compare commercial systems to a consumer system, i dont think an consumer grade thermal plant would last 60 years while it looks like a consumer grade PV system can.
     
  6. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    To the best of my knowledge the older ones no, the newer ones yes.
    Don't laugh, on one contract there was an award for building a cleaner unit and I was told you could see the difference in what was coming out the stack.

    As for the life expectancy of solar PV:
    What Is the Lifespan of a Solar Panel?

     
  7. Walshy

    Walshy Member

    Joined:
    Feb 13, 2002
    Messages:
    353
    Location:
    Brisbane
    Ah, high UV = faster degradation. We can expect relatively short lifespans for panels in Aus, then, what with our very high UV levels.

    Still, 1% per year means you should be getting quite useable amounts of power out after 30 or 40 years.

    Indeed, the 2012 Australian Energy Technology Assessment[PDF] lists a useful life of 30-40 years for solar PV.

    And while the panels last a long time, one of the biggest ongoing costs for PV is replacement of inverters, which are assumed to have about a 10-year life, though I'm sure we've all heard stories of cheaper models that struggle to make it to five...

    As for overall cost - the chart on page 57 of the 2013 AETA Update [PDF] gives a cost for non-tracking Solar PV of $60-190 / kWh, compared to ~$60-105 for black coal, and $70-120 for brown coal. At the bottom end, solar PV is price-competitive with coal, on a raw LCOE basis (Levellised Cost Of Electricity, which includes capital costs, operating costs, fuel costs, interest on loans to build it, etc etc). However, that doesn't account for transmission networks needed (many renewables need to be built in remote areas), or value of dispatchable capacity, on which basis coal & gas are far 'superior' to solar & wind - you can always keep a stockpile of fuel available to keep the turbines spinning, but you don't have that luxury with solar or wind (which is where storage like the Tesla or Redflow solutions come into play, but they add significantly to cost - last time I took a quick look at the numbers, it was up to $500/MWh on the LCOE, which makes it more expensive than any other electricity source examined in the AETA, but I'm quite prepared to admit I got my maths wrong if someone has done a proper assessment for that kind of storage).
     
  8. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    Batteries don't last, that's the problem. Even Redflow needs to be taken offline for regeneration once per month for an hour. Fine if you've got a lot of units. Claimed life is 10 years but can be refurbished at 50% cost of buying new.

    Going by published figures for 90% DoD and 80% capacity retention: Lead Acid is good for 200 cycles, Li-Ion 500 and LiFePO4 2,000. That's not just expensive, it's a lot of resources and energy needed. I see no reason to doubt your figures.

    The original plan to avert catastrophic warming was to use fission as a stop gap until we got fusion to work. A few accidents have impacted that plan. So the fusion effort has been accelerated and those working in the field are worried about this because we do not have the knowledge to make reliable predictions about what happens in a burning plasma. Two centuries of work and fluid dynamics is still a dark science. So ITER, our most expensive science experiment is a shot in the dark forced on the scientific community by the politicians but for the right reasons, we're running out of time.

    By comparison the LHC was a trivial machine to design, a very high level of confidence it would work as intended. All that was needed was Maxwell's equations. Maxwell's equations also apply in a hot plasma but in a Tokomak there's many modes, constructive and destructive interference etc.. It's the same as trying to predict the weather, Boyle's laws are all that's needed but...
     
  9. ernie

    ernie Member

    Joined:
    Dec 2, 2002
    Messages:
    17,103
    Location:
    Brisbane
    Yet Tesla quote 100% DoD, daily cycle, and 10 Year warranty.

    https://www.tesla.com/en_AU/powerwall

    That's way better than what you are quoting.


    - Ernie.
     
  10. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    Here's the specs from the people who make the cells:

    http://industrial.panasonic.com/cdbs/www-data/pdf2/ACI4000/ACI4000CE17.pdf
    At 1C discharge over 500 cycles capacity drops to 80%.
    Tesla's specs imply discharge is limited to around 0.5C. Panasonic don't have any data for other than 1C but if life was better at lower discharge rates I'd think they'd give data showing that.

    Tesla's specs do not say what you think they say. It's an all too common trick with specifications, each one is true but not all in combination. Think of it this way. 10 years of daily full charge / discharge is around 23 MWH. If my calculations are correct that's around $0.025 / kWh assuming $10K for the Powerwall. If that were even remotely possible our problems are over, I'll take 10 NOW for load deferral, no need for solar panels.


    Tesla Powerwall: What's the verdict from the family who installed Australia's first unit?

    If what you're saying was correct Mr Martin is wrong, I could get payback on a Powerwall in under 2 years.
     
  11. RnR

    RnR Member

    Joined:
    Oct 9, 2002
    Messages:
    17,367
    Location:
    Brisbane
    I believe your number is wrong - I get $0.43/kWh (10k / 23k?). Last time I looked at storage costs for utilities, a few years ago now, the price was somewhere around 1c/kWh. I would fully expect a mass produced recent tech to beat this value.
     
  12. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    Well I was using a different cost price, assuming no loss of capacity over 10 years and rechecking I think I was getting the cost per watt hour :(


    Even at 5c/kWh for commercial in Sydney load deferral would be very attractive. I don't understand how apart from pumped storage utilities could be paying only 1c/kWh. I've looked at a few options both for load deferral in a commercial building here in Sydney and for an off grid system in a remote location where power costs 56c/kWh and I couldn't get close to a viable alternative to just buying power off the grid. The only thing that does look viable is grid tie solar PV on a commercial building with a large roof without storage.
     
  13. RnR

    RnR Member

    Joined:
    Oct 9, 2002
    Messages:
    17,367
    Location:
    Brisbane
    I think you are right mate. I have searched on my own posts and found a 1-2c/kWh statement in 2011, but no links unfortunately :rolleyes:

    The figure of 43c/kWh compares well with the rough price for the redflow home battery.

    http://reneweconomy.com.au/2016/redflows-hackett-were-better-than-teslas-home-battery-storage-13405


    Anyways... should we lock this thread? It has massively derailed into renewable energy discussion. Back in the day when the thread started there was alot of new threads being started about the various climate change discoveries, but thats nearly 10 years ago now. I think the frequency of new threads with climate change discoveries would be ok now to coexist in the main ebb and flow of the Science forum.

    Thoughts?
     
    Last edited: Aug 6, 2016
  14. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    I think the way this thread gets diverted reflects the flow of the discussion in the community. There's certainly no shortage of new science but it certainly doesn't seem to attract the media or public attention that it should. I try to fathom the psychology at work here. It's not a problem like what's happening to a past prime minister but it seems that's where it's now being relegated.

    As for closing this thread, yes, probably. The number of new discovers has dwindled, most of the science news seems to only confirm what was already predicted. Much of it seems to only surface on slow news days.
     
  15. antipody

    antipody Member

    Joined:
    Jul 28, 2001
    Messages:
    5,039
    Location:
    Small World
    Wow... heard this on the radio last night and had to try super hard to not choke on my own vomit.

    Politics in Australia is plumbing new lows...

     
  16. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    Unfortunately it's not just Australia. One comment from I cannot remember who summed it up by saying "we're in a post factual period".
     
  17. ernie

    ernie Member

    Joined:
    Dec 2, 2002
    Messages:
    17,103
    Location:
    Brisbane
    Robert's was from the mining industry, so he is going to try and protect and promote those jobs in QLD.

    His claim that there is no evidence that human use of hydrocarbon fuels effect climate, will be controversial. There are many people that don't believe CO2 causes climate change. It certainly hasn't been proven to my satisfaction, though I will admit that it's possible.

    Malcolm has spent the past 8 years studying and writing about the political scams in climate science eg. climate gate, carbon tax etc. He is not some n00b that's just jumped onto the climate debate band wagon like a lot of politicians, he is quite passionate about it, and very well informed, probably more so than any other politician in Australia atm. Being from an engineering background, he is not as smooth a public speaker as most politicians who trained for politics are.

    One thing I noticed about that speech, is when he makes a claim, he often doesn't cite the source, that is not a good thing if you are going against the popular viewpoint. I am familiar with most of the sources of the claims, but the average viewer isn't, so it doesn't go down well.

    It will be interesting to see if he has any impact on the climate debate.


    - Ernie.
     
  18. Walshy

    Walshy Member

    Joined:
    Feb 13, 2002
    Messages:
    353
    Location:
    Brisbane
    Some might say "very well misinformed"...

    I rather suspect he doesn't quote sources, because pitting a bunch of right-wing climate denial blogs or retired coal industry consultants against a few thousand climate science PhDs just doesn't cut it when it comes to 'bolstering credibility'...

    As for the CO2/climate link not having been proven to your satisfaction - well, you must have a very high bar. So high, you really should stop taking advice from anyone without at least a few decades of training & experience in the field you're looking at, with a track record of being almost 100% correct in their predictions...

    Needless to say, that excludes all politicians! :lol:
     
  19. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,251
    Location:
    Sydney
    I wouldn't tar all ex mining industry people with the same brush. Ian Dunlop is past chair of the Australian Coal Council and very, very outspoken on this topic and scathing in his attack on both of our party's lack of commitment to action.

    There's two "classes" of deniers, those who deny our planet is warming and those who deny it's anthropogenic.

    The first are on very shaky ground, it's so easy to prove, no need for a PhD. Just drill a hole through a mass of homogenous bedrock and plot the temperature. Once you're deeper than a few metres the plot should be a straight line and it isn't. Do the maths and you find very positive proof that our planet has been warming for a century.

    The "not our fault" or "not CO2's fault" mob are admittedly harder to prove wrong without getting them to accept the work of science. The more reasonable position and one that I held for some time is us humans seem puny compared to the size of our planet. Then one day it really dawned on me that whilst our planet is indeed so massive we're irrelevant the biosphere isn't. Roll the entire biosphere up into a ball and against the size of our planet it's tiny.

    The second realisation is that our planet's climate whilst it cannot change much over a human lifetime due to its mass it is a very unstable system, tiny pushes over time can tip it either way and once it starts to shift it will swing a long way making human habitation very challenging. Even if one were to argue it's not anthropogenic you cannot deny that we're racing headlong into a massive problem.

    To me it comes down to this: If we knew that at the end of this century an object of significant size was going to collide with our planet would we all not be demanding dramatic action? Perhaps an asteroid crashing into our planet sounds too dramatic but one only needs to read the news of unprecedented floods, droughts, cyclones, wild fires and ice masses retreating to get the sense that something is inexorably happening. Who or what's to blame seems a second order consideration to me. What's alarming is our lack of any action, we still seem trapped in some dream that we can continue along the same trajectory and I cannot find a single indication that supports that reasoning. Even the current state of the global economy says something is happening.
     
  20. MR CHILLED

    MR CHILLED D'oh!

    Joined:
    Jan 2, 2002
    Messages:
    162,096
    Location:
    Omicron Persei 8
    Dire predictions for the next 1000 years.

    So if world conflict doesn't get us, then the climate changes certainly will.

    "Today's greenhouse gas levels could result in up to 7 degrees of warming"

    http://www.smh.com.au/environment/t...-to-7-degrees-of-warming-20160926-grojp8.html

     

Share This Page

Advertisement: