Installation of rooftop solar water heaters is increasing worldwide, according to the Earth Policy Institute.

Recently a post was made on a group I subscribe to touting the amazing usefulness of a webpage that calculates amps * volts = watts for you. All well and good (if a bit simple), but I commented that the basic premise, although good for dc, was flawed with ac. This caused great consternation in the group, as if I said the Pope wasn’t Catholic. I then explained that if you have a 1200w resistive load at 120vac, then yes, 1200 / 120 = 10a. But, and it’s a BIG but, if the load is a reactive load (motors, computers, fluorescent lights, etc.), a fourth entity comes into play, called Power Factor.

In this case, lets say a motor has a PF of .5

Now things look very different. We have our 1200 watt load / 120 vac = 10 amps. Now divide the 10a by the power factor .5, and we get 20 amps. That’s a much heavier load, requiring heavier wiring, and a bigger generator or inverter. This may help explain why some folks have problems with some loads and not others, that go beyond simple start up surges.

For more info, see http://arduinotronics.blogspot.com/p/tutorials.html

©2012 Green-Trust.Org. All Rights Reserved.

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The Howard Johnson (HoJo) Motor is a recurring scam that’s making the rounds yet again. Purporting to make free energy from no inputs, the attempt is made to convince the gullible that magnets are a source of energy, instead of just a facilitator.

Magnets help in the conversion of energy from one form to another. Take the alternator for instance. When a coil of wire is passed through a magnetic field (permanent magnets or a electromagnet), a current is produced. It’s not magic, it doesn’t “just appear from nothing”, the energy comes from whatever is pushing the wire (or pushing the magnets). When you attach a load to the coils, it becomes harder to push. The required push is associated with the load you are trying to pull. The more power you pull (adding more loads), the more energy is required to push the fields. There is no “excess power”, “free power” or free lunch. It takes energy to convert energy from one form to another, and always with a loss of some of the energy as heat (friction). You can’t break even, never mind pull ahead. Terms like “Zero Point” energy or “over-unity” are a dead giveaway to scaminess.

©2012 Green-Trust.Org. All Rights Reserved.

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A Charge Controller protects a battery bank from over or under charging. In typical solar applications, when the battery is full, the panels can be disconnected. In wind and hydro apps, the turbine could be damaged if disconnected, as the load keeps it from overspeeding and self destructing. This controller fixes that problem by bringing on a dump load when the batteries are full. Typical dump loads are water or air heating elements. We prefer water heating elements, that heat our hot water tank anytime the batteries are full. It’s a good way to utilize what would normally be wasted generation.

Commercial charge controllers can be pricey, and we have several units in various voltages at http://essnmag.com/wordpress/products/, but you can build your own controller as well. One of the more interesting dump load controllers is based on a 555 Timer chip, and fairly easy to construct. It’s a good match for a home built solar panel. You can learn how to build this unit at http://www.mdpub.com/555Controller/, and discuss topics like this at http://groups.yahoo.com/group/12VDC_Power/ and http://tech.groups.yahoo.com/group/DIYSolar/.

©2012 Green-Trust.Org. All Rights Reserved.

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Nothing is more satisfying than designing and building your own home. You can save a chunk of dough in the process, but it’s living in a home that you designed to meet your particular needs that really puts a satisfied smile on a person’s face. I started out as a kid designing several tree houses (some of which were good), as well as various farm and camp buildings as a teenager. My dad and I designed and built a log home in the mid 80′s, and I’ve been designing shelters and gadgets ever since.

One of my favorite materials discusses building your own home with green wood. Oak specifically, but if you don’t have a woods full of oak, pine and other types of wood could be substituted with allowances and variations. Oak twists and splits less than other woods, but poplar is a good substitute.

If you have a chainsaw, your own woodlot, and a a jig for making straight cuts, you could easily build a small home for less than $20,000

Here is a free resource that will teach you how to build with green wood, and control warping and splitting:

http://raincentre.in/The_Green_Wood_House.pdf

©2012 Green-Trust.Org. All Rights Reserved.

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