1. Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
    Dismiss Notice

Solar Concentrator

Discussion in 'Renewable Energy' started by crashsite, Jan 5, 2008.

  1. Pommie

    Pommie Well-Known Member Most Helpful Member

    Joined:
    Mar 18, 2005
    Messages:
    10,022
    Likes:
    317
    Location:
    Brisbane Australia
    Unlike Ammonia, a Lithium systems runs in a vacuum.

    Mike.
     
  2. rjvh

    rjvh New Member

    Joined:
    Dec 20, 2007
    Messages:
    863
    Likes:
    6
    Location:
    cambodia
    and how much is your underpressure??
    vacuum is just negative pressure
     
  3. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

    Joined:
    Nov 17, 2003
    Messages:
    39,231
    Likes:
    641
    Location:
    Derbyshire, UK
    ONLINE
    Two points - first I live in the country, and always have done, second, air-con is extremely rare in the UK - I certainly don't have it, and probably don't know more than one or two people who do?.

    If you would prefer me to be more accurate, it's not 'financially' viable - if you live in the middle of nowhere financial viability isn't a concern - just something that works is.
     
  4. dave

    Dave New Member

    Joined:
    Jan 12, 1997
    Messages:
    -
    Likes:
    0


     
  5. rjvh

    rjvh New Member

    Joined:
    Dec 20, 2007
    Messages:
    863
    Likes:
    6
    Location:
    cambodia

    england what about a sollar water heater for your hot water supply :D
    the problem with england is the same as holland (where i am orriginaly from) lack of sun hours
     
  6. Pommie

    Pommie Well-Known Member Most Helpful Member

    Joined:
    Mar 18, 2005
    Messages:
    10,022
    Likes:
    317
    Location:
    Brisbane Australia
    You should never ever exceed 1 bar of vacuum or the whole universe will be sucked in.:D

    Mike.
    P.S. what is negative pressure?
     
  7. crashsite

    crashsite Banned

    Joined:
    Nov 20, 2007
    Messages:
    725
    Likes:
    3
    You make some good points. I suppose that once you make the ice you could use it to cool the house the next day but, you are right. The amonia system doesn't work in "real time".
     
  8. Pommie

    Pommie Well-Known Member Most Helpful Member

    Joined:
    Mar 18, 2005
    Messages:
    10,022
    Likes:
    317
    Location:
    Brisbane Australia
    Ammonia systems do work in real time. Check out any gas powered fridge, they use a small gas flame to run the refrigerator.

    Mike.
     
  9. crashsite

    crashsite Banned

    Joined:
    Nov 20, 2007
    Messages:
    725
    Likes:
    3
    Using ammonia as the working fluid in a refrigerator does work in real time but, the ammonia chloride system (that was referenced and was described in a link from an earlier post) cycles, with the cooling being done in off-sunlit hours. Sorry, I probably didn't put in enough, or the right, parts of the quote to clarify.
     
  10. rjvh

    rjvh New Member

    Joined:
    Dec 20, 2007
    Messages:
    863
    Likes:
    6
    Location:
    cambodia
    negative pressure is suction

    and for the ice storage it can cool your house but do it properly you have to think about it with the building design of your house
    water walls or piping with water circulation is a good option but a head ache in an exsisting house
     
  11. Pommie

    Pommie Well-Known Member Most Helpful Member

    Joined:
    Mar 18, 2005
    Messages:
    10,022
    Likes:
    317
    Location:
    Brisbane Australia
    There is no Ammonia Chloride system.
    All systems cycle.
    All systems can be made to work in real time. They just get a bit more complex.

    Mike.
     
  12. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

    Joined:
    Nov 17, 2003
    Messages:
    39,231
    Likes:
    641
    Location:
    Derbyshire, UK
    ONLINE
    There have been various solar water heating schemes over many decades, the problem (as always) is down to how viable they actually are!.

    The 'Centre for Alternative Technology' (C.A.T.) in Wales does a lot of work in that line, and is well worth a visit if you're ever in the UK - makes for a great day out.
     
  13. crashsite

    crashsite Banned

    Joined:
    Nov 20, 2007
    Messages:
    725
    Likes:
    3
    Calcium Chloride

    I went back and looked at the referenced article and here's a paragraph. It's actually "calcium chloride" (my faulty memory):

    "Our intermittent absorption solar icemaker uses calcium
    chloride salt as the absorber and pure ammonia as the
    refrigerant. These materials are comparatively easy to
    obtain. Ammonia is available on order from gas
    suppliers and calcium chloride can be bought in the
    winter as an ice melter."
     
  14. rjvh

    rjvh New Member

    Joined:
    Dec 20, 2007
    Messages:
    863
    Likes:
    6
    Location:
    cambodia
    i am familiar with your reference article
    but this article is published a few years ago and this guy is from canada
    plenty of calsium chloride there but in cambodia it's not that easy to obtain
    i bet in brisbain it's also not a common good that you buy on every street corner
    amonia is again a different story
    in a country with some industry it will be availible but after 9/11 people ask a lot more questions what you gona do with it
    it's still nasty stuf which you can use in manny nasty ways

    as for the sollar shemes in overcast windy and rainy parts of europe
    i class england in that category
    that is just showing the will to do somthing about it than that it makes sence
    max energy what the sun deliver on 1 square meter is 4.8KW a day (12hours)
    thats in quatar, sahara, texas and australia
    your are extreemely good to build a sollar colector with an efficiency 65%
    you can tweek it but to get 10% more cost you 50% more
    that leaves you a bit more than 3 KW:12 Hours = 250watt an hour
    how manny sun hours you have in england ? (holland is 51% sunny of the total sun hours a year)
    but temp is a lot cooler and the chill factor is also a problem because i tend to be always windy
    this can be tackled severals ways but it ad on the cost of making the colector
    a sollar collector is by far the most efficient way to get energy from the sun but is comecialy only intresting if it is heavely subsidized (which is in europe the case)
    or in sunny parts of the world year round
     
  15. Pommie

    Pommie Well-Known Member Most Helpful Member

    Joined:
    Mar 18, 2005
    Messages:
    10,022
    Likes:
    317
    Location:
    Brisbane Australia
    Calcium Chloride is readily available as damp absorber in most supermarkets. If it isn't available then Calcium Carbonate is available as ground up sea shells. Mix Calcium Carbonate with Hydrochloric (muriatic) acid and you have the Chloride. Ammonia is also available in the cleaning section - it's weak but can easily be strengthened. Ammonium Sulphate is available as fertiliser, mix it in solution with Calcium Hydroxide (slated lime - builders supplies) and you have weak Ammonia solution (+Calcium Sulphate as a precipitate).

    As you can see most chemicals are available, you just need to know where to look.

    Mike.
     
  16. rjvh

    rjvh New Member

    Joined:
    Dec 20, 2007
    Messages:
    863
    Likes:
    6
    Location:
    cambodia
    you've ever been in cambodia ???
    the outback in australia is better stocked then here

    if you know what we have to do to get the simplest things here you would be supriced
    it's now much better than 7 years ago but still a big hassle
    i never came acros ammonia here not even the weak one for cleaning
    everybody is talking about pic ic these days
    i can't buy even a simple opto coupler, +/- 7 different numbers of the Cmos 4000 family is availible here not more
    solenoid valves 12V and 220V availible only in one size (to small where i need them for)
    ect ect
     
  17. crashsite

    crashsite Banned

    Joined:
    Nov 20, 2007
    Messages:
    725
    Likes:
    3
    Christmas Morning

    We (especially us Americans...although I know that will irk a few other "first-world" users here) often do not appriciate that every day, for us, is like Christmas morning when it comes to having/obtaining material things.

    But, I would comment to you that there is a famous saying in the selling business: "Adversity brings opportunity". Cambodia is pretty hot. I've never been there but, I've been to Singapore and, that zone is just hot every day!

    Some enterprizing Cambdian will likely find a way to take advantage of that tropical sun and make a pile of cash. Perhaps selling "low cost cold" could be one of them?
     

Share This Page