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Viewing 10 posts - 16 through 25 (of 25 total)
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  • in reply to: Are heat lamps the most efficient heat source? #64128
    j_pigden
    Participant

    For a more exact explanation, you need to look at thermodynamics, heat and energy transfer texts.

    Heat transfer uses 3 ways, convection, conduction and radiation. Convection warms air which moves because warm air is lighter and floats upward. Conduction warms by touch (the basis of convection). Heat lamps are radiation. Use only heat lamps and your pipes will burst (they only heat where they are pointed)!

    When the lamp gets hot, that is wasted energy. For a more efficient process use QH bulbs.

    in reply to: #64127
    j_pigden
    Participant

    The difference is the width of your concern.

    If you are interested in the ‘global’ impact, then, yes battery production is an energy pit.

    Myself, I’m more concerned with my own survival. Since battery devices hit my pocket less than wired devices, I go battery. BUT, watch out for corded recharge stations, the ‘vampire’ electrical costs can be HUGE!!!

    in reply to: bild it your self (D.I.Y enegy) #64065
    j_pigden
    Participant

    You’ve hit both ends of the spectrum at once; solar panels are impossible, the others easy.

    A small amount of study into energy and motion and you can build your gear:

    solar water heater – reflector to focus sunlight, dark coloured container to absorb energy and hold heated water

    wind turbine – any DC fan, the larger the better.

    What you pay for is efficiency, packaging and marketing!

    in reply to: Need Help – Solar Powered Fan #64052
    j_pigden
    Participant

    If you are talking about SLA (sealed lead-acid) batteries, then this is sort-of correct.

    Photo Voltaic Arrays (PVA) don’t behave the same way. They convert the energy in light into current flow. As long as there is light there is current flow. Batteries, on the other hand, convert a fixed amount of chemical energy into electrical energy. When the chemicals are gone so is the energy. If the energy draw is too much, the battery can suffer a pole-reversal from negative to positive. Rechargable batteries have the ability to convert the low potential energy chemical matrix into a high potential energy state through the addition of current. They have a limited number and range of this chemical reaction which sets the life of the battery.

    PVA’s don’t work this way. They take the energy from the sun and convert it into current flow. They don’t use chemical conversions and so, don’t suffer chemical breakdown like batteries. They are a source of energy to the battery array.

    Without any actual values, the words can sound scary but when the terms of the test are known, the claims lose their power.

    For this situation to occur, the battery chain must start fully charged, be used constantly until dead, then recharged fully, then used constantly until dead, ad infinitum. The real world is rarely like that. Every time the circuit is opened, the batteries create a gentle recharging effect that tends to even out the load to all the batteries. In addition, the recharging circuits in PVA’s control current flow to prevent overcharge and to deal with potential pole-reversal.

    A case of apples and oranges.

    in reply to: Need Help – Solar Powered Fan #64048
    j_pigden
    Participant

    1. Look for a ratings label on the fan housing on the motor body

    2. Try hooking the solar panels in parallel and see how the fan does

    3. Capacitors only store energy, you need to provide an energy source

    YOU NEED MORE PANELS

    in reply to: Need Help – Solar Powered Fan #64042
    j_pigden
    Participant

    The problem isn’t voltage, it’s amperage!

    You wired the panels in series(4.5v * 2 = 9v) but 50mA. The muffin fans that I have need about .1A at full speed (40 panels in a parallel/serial array)!

    1. wire the panels in parallel (lower voltage but higher current) fan will turn slowly.

    2. switch to a rechargable 9v for occasional use & use the panels to recharge the battery.

    3. use solder connectors & large gauge wire to bring the power from the roof.

    in reply to: Just built a ram pump, for anyone interested #64046
    j_pigden
    Participant

    Ontario Hydro has used the ‘storage pond’ idea since the 40’s @ Niagara Falls. The pond is filled with diverted water at night then released to the turbines during the day. The process was originally coordinated by telephone but is now automated!

    in reply to: fresh air to electric #64045
    j_pigden
    Participant

    Unfortunately, the only ‘fresh air’ left in the world is over Antarctica, but it will be gone by the time you get there!

    in reply to: cycling generator. #64044
    j_pigden
    Participant

    YES, it does work!

    There are actually 6 setups like this at the Science Center in Toronto. They were put in about 40 years ago. The front wheel of the exercise bike has a fanbelt going to an alternator at about 15-1 ratio. The original design was army signal corps about 1942. It was used to recharge batteries and run radios in remote areas.

    in reply to: small home solar advice needed #64043
    j_pigden
    Participant

    You need to figure out what demand you need; voltage, currrent load, usage timings, orientation, etc. first, than you can ask for specifics.

Viewing 10 posts - 16 through 25 (of 25 total)