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  1. Renewable Energy

    1. Starting In Solar? Feel free to introduce yourself

      Starting in Solar? New Comers Feel Free to Ask- There is no such thing as a silly question.

    2. General Discussion

      General discussion & Latest renewable energy news

    3. Questions & Answers?

      Unrelated To Renewable Energy. E.g. How To Prepare A Wall For Painting?

    4. Off Topic

      Off topic discussion, World News & Current Affairs

    5. Product Opinions & Reviews

      Renewable energy product opinions, reviews & questions

    6. Member Installations Showcase

      Please feel free to showcase your renewable energy installation, share, upload images & installation descriptions

    7. Solar Power

      Solar power discussion

    8. Wind Power

      Wind power & Wind turbine discussion

    9. Batteries

      Batteries, battery monitors, chargers, accessories & battery care

    10. Inverters

      Off Grid & Grid Tie inverters

    11. 160
    12. Accessories

      Cables, Circuit Breakers, Fuses, Electrical Accesories

    13. Water Heating & Pumping

      Water heating & water pumping solutions

    14. Hydropower

      Hydropower or water power is power derived from the energy of falling water or fast running water, which may be harnessed for useful purposes

    15. Sustainable Landscaping

      A sustainable landscape is a stable and productive ecosystem that conserves the physical and biological processes occurring on that landscape. Designed and managed sustainable landscapes maintain hydrological function, plant and animal diversity and biomass, soil integrity, and contribute to human wellness. Utilizing nature and landscape to promote energy efficiency and energy saving.

    16. Energy Use & Conservation

      Saving energy, energy saving appliances & tips

    17. Electric Vehicles

      An electric car is an automobile that is propelled by one or more electric motors, using electrical energy stored in rechargeable batteries or another energy storage device

    18. Alternative Fuels

      Some well-known alternative fuels include biodiesel, bioalcohol (methanol, ethanol, butanol), chemically stored electricity (fuel cells), hydrogen, non-fossil methane, non-fossil natural gas, vegetable oil, propane, and other biomass sources.

    19. The Internet of Things

      The Internet of Things (IoT) is the network of physical objects—devices,other items embedded with electronics, software, sensors, and network connectivity, that enables these objects to collect and exchange data. Such as : Raspberry Pi, Arduino

    20. Fundamentals Of Electricy

      Principles of Electricity, Theory , Calculations

    21. Industry, Product Hypes, Fads & Rants

      Hypes, Scams, Rants, Unproven Tech, Does it really work?

    22. Useful Resources

      Share Useful Resources

    23. Design Software

      Software to aid in the design of Renewable Energy Systems.

    24. 211
    25. Electronics & Tools

      Gizmo's , Ipads, Tablets, Smart Phones, Tools, Power Tools

    26. 59
    27. Group Buys

      Buying as a group local or abroad.

    28. Hobbies

      Gadgets, Electronics, Fishing, Cars, Remote Controlled Vehicles, Drones, Photography, Camping, 4x4, Boating. Anything Goes :>

    29. Classifieds

      For sale and Wanted
      Commercial Suppliers Please make use of the Commercial Supplier Section

    30. Job Centre

      Post job opportunities here, or upload a copy of your CV if you are seeking employment in the renewable energy sector.

    31. Commercial Suppliers

      Suppliers to sell goods on the forum as part of a business. Companies, Sole proprietors and anyone who wishes to advertise products for commercial purposes are most welcome. To apply please visit  http://powerforum.co.za/subscriptions/

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    32. Forum Suggestions & Support

      Suggestions & ideas are always welcome to improve Power Forum

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      Get your broadband and tech questions answered and share your thoughts on gadgets, SA’s Internet and cellular networks.

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    • Hi,  Ok, some info re "life expectancy".   A manufacture regard 80% capacity as end of life.  Most lithium packs do about 500 - 3000 cycles (2-10 years) if you partial cycle them (50-80%), then after those cycles you have 80% capacity left..  Now also, remember lithium gets damaged when fully charged , the opposite of lead acid that get damaged when not 100% charged Now we go buy "dead" laptop battery with "80%" capacity left and they have  not seen any charge for years (so no extra damage really occurred).   You test each cell by charging/discharging them and then sit them one side to see if they self discharge.  Any cell below 4.0v after month go to the use for something else pile.  If they get hot on charge, they go in bin immediately. Now the cell might have been 2500mah  when new. Now its a 2000mah after 5-10 years of use (80%).   That is still a lot for what we need, we don't care about weight etc, so can simply add more cells.  Even 1000mah is perfectly fine if they don't self discharge and don't get hot on use.  Its just double the amount of work (or triple of new cells).  I used anything above 1300mah tested capacity . So our cells should give us  another 5-10 years of use with only a reduction of 20-30% of capacity (of course, will only know that in 5-10 years). So in theory we will then still have 70% of our current capacity, which is still more than what we need.  If I can get 5-8 years out of this pack, its same or more than  Lead acid in real world  and at 2% of the price with no worry making sure water levels are right, room is ventilated its a no brainer.    There article somewhere about Tesla cars (same battery tech) and there battery life expectancy is 25 years with daily use, or more than the life of the car.   
    • Tisk Tisk Tisk, we expect more from people like you in this day and age, just getting with the times I guess
    • Great to see someone getting a DIY pack up and running, well done. My only issue with laptop batteries (and please correct me if I am wrong) is that you are using Li-Ion (3.7/4.2V) and not Li-Iron (LiFePO4 - 3.2/3.7V) - My problem with Li-ion is that the average life expectancy is 300-500cyc when the battery is new. The laptop batteries that you are using are used, and although I assume that you are testing them and discarding the dodgy ones, the ones being used are probably 1/2 life by now. So have you allowed for the fact that the pack may die within 150-250 days, or am I getting this all wrong?
    • Seeing that eksdom forced my hand, Had to install my pack this weekend ..   Its about 180ah usable capacity at 1C and easily handles our 500w continues load and I ran the  aircon few times , 1800w 80A at battery level, to check cable tempts etc.   What the nice part is … after power came back on, took 40 minutes to fully recharge at 0.1c .  I increased the charge level to 0.25 and we had  a ~3 hour power failure last night and recharged fully in 1hr  when power came up.  The  Pack is set to charge to 4.05v per cell (Lithiums don't like being charged to full capacity). Float at 4v. I also ordered a Batrium battery management system (cost double the price of the battery bank, but need a balancer that plug and play with inverters , no time to build own now) so will see how goes then.  Then its to solder the other 500 cells to get pack to final size. Will also try do a full discharge to see what true capacity of the pack is , should be about 30% more than the 1A discharge tests as each cell now only see a load off about 0.05c at normal load .. so in total its should be about  ~R 11k  with management for a usable(not total) 10Kwah bank. So thats same as about 30Kwah lead acid bank (if my calcs are right ).          
    • On the side of the defence: This is the off-topic section of the forum... :-) On the other side: One must be careful what one says, for things can easily be misconstrued. Especially in this day and age of SJWs. Oh look, I just used a term I detest (day and age). No consistency either.
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