Home Power tests an Ancient PV Panel

We've been telling you that photovoltaics last a long time. Well, here's living proof that PVs can handle the LONG haul. This venerable PV panel has been in the sun for more than 10 years and still produces more than its rated output. Amazingly enough these silicon marvels don't seem to wear out. In the Spring of 1977 the US Energy R& D Administration spent one million dollars on a PV powered irrigation project in Mead, Nebraska. This venture was conducted by Lincoln Labs of MIT and the...

John Millard

I have been a renewable energy buff since the 1974 energy crisis. Windmachines for generating electrical power always fascinated me. In 1974, I bought a 200 Watt 12 Volt windcharger and installed it on a 35 foot steel tower. It generated a small amount of power for the house. At the time, I had 5 24V aircraft 35 Ampere-hour batteries (wired in series to produce a pack of 130 VDC). The batteries fed a 1kW. rotary converter, 130 VDC in and 120 vac out, which ran the house. The 12V output of the...

Gary Starr

The summer of '88 brought the worst drought North America has had in 50 years. Crop losses were in the billions. Forest fires blazed throughout the Northwest, the Great Plains and Yellowstone National Park. On the other side of the globe, China was also experiencing horrendous drought and related crop damage conditions. Over a million people were hospitalized, and hundreds of other died from the heat. Was it a mere coincidence Or a warning A warning that nature was rebelling Until this year...

Appliances Q vac via inverter Q VDC from Batteries

Figure 1- Rancho Chatuco's Estimated Electrical Power Consumption from pumps to bulldozers on site . This hulk of a unit is located some distance from the rancho's main house where no one has to listen to its considerable racket. Power Source Control A Heliotrope CC-60 PWM charge controller is wired in series with the PV array. This unit assures that the batteries store as much of the PVs energy as possible without being overcharged. The Heliotrope controller was equipped with the optional...

More on Entropy

In the last issue I discussed entropy in terms of information and energy. Through an analogy with Special Relatively, I theorized that increasing the spacial order of a system increases its temporal order. Thus, its energy potential is also increased. Does a way exist to increase temporal order directly Heisenberg's Uncertainty Principle states that if the time interval is short enough, then the energy transitions that take place during this interval are indeterminate and may violate...

Richard Perez

Here's a simple, home-brew, project that indicates how much energy is remaining in your batteries. It's a gas gauge for lead-acid batteries, we call it the Bat-O-Meter. It is an LED bar graph voltmeter with an expanded scale. It can tell you the state of charge of your batteries from across the room, even in the dark. The Bat-O-Meter is not only very simple to build, but also very inexpensive-less than 10. in parts and about an hour of your time are all that's needed. And, in addition to the 12...

Horace McCracken

Homemade Solar Distillation

Practically any seacoast and many desert areas can be made inhabitable by using sunshine to pump and purify water. A 10 gallon day solar still now purifies sea water for drinking, cooking and other household needs for a residence near George Town, Exuma, in the Bahamas. Solar energy does the pumping, purification, and controls seawater feed to the stills. This system uses three solar distiller pans 33 wide by 10'3 long. They are insulated, lined with a special corrosion-resistant membrane. The...