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About hakonnissen

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    Somerset West, Cape Town

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  1. hakonnissen

    Turbines - Where to Start?

    Thanks@PaulF007. I've dealt with ZM before. They gave me very helpful input. @Tim in my research and experience your 15% is WAY off the mark. I typical micro hydro system operates at about 50% efficiency, but can increase dramatically with scale (ie large hydro generators could be 75-80%). A hydro system is complicated. The first loss of efficiency is to friction in your feedstock (pipeline). This varies greatly depending on pipe size & type. My pipeline is running at about 98.9%. The 95+% which ppl generally quote is the efficiency of the turbine itself in converting the linear flow of water out of the nozzle into rotational energy on the turbine shaft. Then u loose efficiency to friction in the shaft (negligible), electrical conversion (about 65% efficiency, if memory serves) and lastly electrical transmission (about 98%+ efficiency). This will give you about 50-60% efficiency to get AC electricity. You will have further losses if you need to rectify to DC (theoretical 80% efficiency), and battery storage is a separate issue which also has inherent losses in storage turnaround. My rule of thumb for my system is 50% efficiency. Sent from my HUAWEI GRA-L09 using Tapatalk
  2. hakonnissen

    Power spout

    DeepBass9, I'm also considering something like 100KL as a long-term solution similar to yours. Batteries are a FAR more efficient way of storing power (92% round-trip efficiency for LiFePO4 batteries vs something like 40% efficiency for small-scale pumped storage), but if I'm pumping with excess solar / wind, then I don't really care about the efficiency. Battery replacement costs also play a BIG role. If I'm going to have to spend R50k+ every 5-10 years, then I'd rather make the effort up-front and install pumped storage, which my grandchildren will still be using with minimal maintenance. I've looked at http://rainqueentanks.co.za/, who make a 100KL reservoir with a 10m diameter for about R25,000, which is a LOT cheaper than plastic tanks. Easier to transport too, as they can sell you the loose sections and the plastic liner folded up.
  3. Most of the cheap turbines I seem to find are either providing "wild" 3-phase AC (ie Voltage fluctuates along with RPM), or are rectifying the 3-phase to DC, which (judging by the heatsink sizes) must surely result in hefty losses. I realise 3-phase is more efficient for generation and transmission, but when I only need single phase 220V, the equipment for 3-phase gets expensive and the load balancing gets rather complicated. My one big advantage with rectifying to DC, is that as my hydro flow fluctuates I should be able to use everything generated (more water = more RPM = more Watts). If I understand correctly AC generation makes use of a dumpload to control surplus energy. If I only want single phase 220V and don't want to waste energy on rectifying to DC and then inverting back to AC for loads, how do I clean the power to ensure constant voltage and frequency?
  4. hakonnissen

    Turbines - Where to Start?

    Hi All We have a small guest farm in the Swartberg mountains, which I'm looking to electrify. What may seem like useless sources to others at least provide me with SOMETHING. I have a natural spring coming out of the mountain 40m higher than my guest cottages and I'm looking at installing a permanent magnet alternator with a pelton wheel on it to generate around 400W. I have scoured the internet and something like the Powerspout from New Zealand looks perfect, but will cost me close to R30,000 delivered to my door! That's an expensive prototype, when I'm not even exactly sure of the capabilities of my system. Does anyone know of a local supplier of such alternators / generators? All the US / NZ websites refer to Fisher & Paykel washing machine motors, but I can only find the Samsung SmartDrive's locally, and haven't found a decent used one yet. Regards Hakon Cape Town
  5. hakonnissen

    Possible Hydro Section

    Thanx a ton!
  6. Hi there I am looking at sharing ideas and getting input on hydro-electric generation. I realise your typical urban user is not the market for this, but feel we could start a separate section for Hydro, with the same status as Solar & Wind. Your feedback would be greatly appreciated. Hakon Nissen