Q & A Dear Home Power Crew, I am writing you in regards to the letter you published in Home Power #4 from Lisa Reynolds of Pearson, WI. She was looking for a 12 VDC color TV with a screen larger then 12 inches. I recently came across a 14 inch TV (12 VDC) with remote control in the Sears catalog. The TV is made by Magnavox and costs approx. $300. The catalog number is 57 B 40751C. Perhaps you could pass this information on to her and your readers. My wife and I enjoyed our visit with you last month and appreciated your hospitality. I was hoping to see you at the Country Fair in Oregon, but our paths didn't cross in the crowd. It took me two and a half hours to get from Eugene to the fair grounds so I arrived late. I am currently working in my "Micro-Cogeneration Unit". This consists of a 6 H.P. liquid cooled diesel engine coupled to an induction generator. I will be collecting the waste heat from the exhaust and cooling system and storing it in a 120 gallon water tank. I am curious about what kind of efficiency I can get from this rig. I will send you a full report if I come up with any good information. Also I will be attending the PV seminar offered by Colorado Mountain College in August. I am really looking forward to this. If you are ever in the neighborhood, please stop by for a visit. Sincerely, David Doty, Gig Harbor,WA Thanks Dave, we enjoyed your visit, too. We're looking forward to hearing from you. I have a Jacobs 2 kilowatt wind generator and plan to use it with a soon to be purchased 8 panel array with tracker. I intend to use the present 115 volt house wiring and, therefore, will run a Trace inverter off a battery bank. My question is this: should I use a rather odd-ball, more expensive 32 volt battery bank, since the Jake's windings were made for this voltage, or a less expensive and more practical 24 volt battery system? I have talked to a few people about this and have gotten quite a range of opinions on the matter. I have been told that a "24 volt Jake" will start producing power and peak out at lower wind speeds, but put out less overall wattage compared to 32 volts applied to its field windings. Considering the specific and consistent wind speeds we have in our hills, 14 to 16 mph for 6 to 8 hours daily, and my desire to get as many watts as possible out of the Jake, what would Home Power suggest? Use the enclosed $10.00 for that illusive and long sought after "free lunch". P.S. If there are any Jake owners out there with info. on this matter, give me a call, or write. Jake Biondo, 19355 El Cerro Way, Watsonville, CA 95076, 408-726-1830 I wish I could give you specific info of the Jacobs voltage converstion, but I've no direct experience in these units. Basic physics does bear out the conclusions you have made so far. It's a matter of current through the windings of the generator. How about it Jacobs nerds? Hi Folks, First, let me congratulate you on your fine magazine. Keep it up! I have built the Pulsar battery charger (HP#5, pp27) and am really pleased with it. There are a couple of questions: Every once in a while, the NiCad batteries being charged get HOT. This happened twice so far, with different batteries, one set being virgin AAAs. I disconnected them as soon as I noticed the heat. They do not seem damaged. What is going on? Is there a fire hazard? I was charging six AA cells the other day, starting at 50mA. I had to trim the voltage at first. Soon I noticed the Ammeter needle creeping down. I kept adjusting up- first the voltage, then pulse width. Within two hours (sunset) the PULSAR was pulsing full bore but couldn't push more than 30 mA. What's going on? Are there self-regulating NiCads? Or can I only do four at a time? Our household has been solar (9 ARCO 2000 PVs) for 7 years now. In winter, there's a Harris unit 1500 feet down the wire, with transformers at both ends if the line. This only works on runoff. To fill the gap, there is a 75 AMP automotive alternator driven by a vintage 1932 B&S 'ZZP' engine. For small AC loads (computer, video) I use a HEART 300W inverter. Power tools and the old Maytag run off of the 1800W DYNAMOTE. All is 12V since I feel switching between 24 and 12 is alot of hassle. I am learning about electronics rigging up 12V power supplies for the computer & monitor. It's nice to have NO HUM AT ALL. We started out with a 500W Sencenbaugh wind generator but were leaping before looking: It is for sale. Bad site. Again, you are doing a fine job of desktop/ mousetail publishing. Thank you. Fritz Oppliger, Redway, CA Sounds like you may have a bad nicad. It is normal for nicads to heat up slightly as they are charged. If you can't touch the battery for five seconds without pain, then its too hot and something is radically wrong. If a nicad has failed in the open circit direction, then it presents a very high resistance, and the Pulsar cannot pump enough current through the cell (and all cells in direct series with the bad cell). On some small capacity batteries, the nicad pulsar may require adjustment of the voltage control to keep current within range for the pack. The duty cycle of the pulsar only reaches about 5% where say 2% may be necessary to regulate the current to the desired level. In this case, use the voltage control to lower the amplitiude of the pulse (its voltage) to the point where the current flowing into the battery is what you wish. Dear Home Power, I have enjoyed your magazine since its first issue, and have gained alot of useful information that I hope to put to use in the future. I would like to ask you or your readers if any of them have experimented with the possibility of using a work vehicle to produce supplemental power for the home, by placing a second battery system on the vehicle, and letting the alternator charge it whenever you need to drive the vehicle? Perhaps your computer could produce some useful charts of electricity production by using the amps of different size alternators, and the time run per week to determine how much power could be produced by each vehicle? Also, what would be the most efficient way to deliver this power to the home? Thanks for any help you can provide, and keep up the good work. Daniel T. Meirs, POB 2500, Lincoln, NE 68502 Yes, this mode of power production is happening. Many of us started out with an umbilical cord to our vehicle's battery. The car's alternator will fill an auxillary battery while the vehicle is running and the energy can be used later in the house. One problem with this setup is that the car must be continually reconnected to the vehicle. I've a friend that got the polarity reversed on this hook-up twice. Both times cost him a very new 12 VDC color TV set. Be sure to use a POLARIZED quick disconnect between the vehicle and the house. When it comes to high amperage alternator it's hard to beat the Chrysler 100 amp models. Unless you use very little electricity, I think you're going to spend a lot of time driving. I have a one room cabin in rural South Georgia and am looking for an alternative energy source for air conditioning. Windmill power is not possible, and I prefer not to use a noisy generator. I am specifically looking for a propane air conditioner or information about it. I have a solar collector and 12 volt battery system that I believe can handle the electricity required to run the fan. I understand there once was a company called Arkla that manufactured these, but that the company was sold and the production ceased. Does anyone out have information on and access to a propane air conditioner? Thank You! Judy McVey, 1693 Mchendan Ave NE. Atlanta, GA 30307 How about it, Readers, anyone know of a propane fired air conditioner? We've several systems in the neighborhood that use PV supplied energy to run evaporative coolers. They work well in areas with low humidity. I have a highhead, low volume turbine, with a wheel made for a 1" jet. The drought in our region has run the ground water so far down that my turbine is from inefficient to worthless depending on the season. I'm in particular need of info on small pelton wheels that are efficient with a 1/4" jet and info on efficient 24 volt alternators. I have a good 1800 rpm, 120V alternator that may be fine, if I can come up with an efficient 6" pelton wheel. Other wise by-pass the charger and produce 24V direct to the batteries with a 4" wheel. Any Ideas? Bill Ruggles, Bakersville, NC Contact both Don Harris of Harris Hydro and Paul Cunningham of Energy Systems and Design. Both are advertisers in this issue and are experts in turning a trickle into Watts. What about kerosene refrigerators? Does anyone sell retrofit carburetor kits to change gas powered generators to propane? As a licensed auto mechanic, I know of kits and how to put them on car/truck engines, but have not yet seen any for small engines. Your magazine is really good! Read them cover to cover when I get it. More Power to You! David St. John, Mad River, CA Well, David, to a physicist it's just plain ass-backwards to burn something to make something else cold. Electric compressor type refrigerators will work in low voltage RE systems. In fact the finest and most efficient refrigerator made are strictly for low voltage operation. Check out Sun Frost refrigerators and freezers. They have a Mercantile Ad in this issue.