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The codfish lays ten thousand eggs, The homely hen lays one. The codfish never cackles To tell you what she's done. And so we scorn the codfish, While the humble hen we prize, Which only goes to show you That it pays to advertise.

Letters to Home Power

Letters printed unedited. We'll print your name &

address if you say it's OK.

Compiled by Karen and Glenda

We really enjoyed getting this copy of Home Power. A friend of ours gave it to us- he got it from Richard Perez's brother Michael in San Antonio-- Michael and Lisa have been friends of mine for over 7 years. Just recently we learned of Richard's occupation. We tried to get a copy of the Battery Book in San Antonio, but Bookstop (the biggest bookstore in the area) has been out for quite a while.

We live on 16 acres in Central Texas about 65 miles North of San Antonio. We have no electricity and a windmill pumps our water. We use oil lamps for light, propane heaters or wood for heat (also propane stove) and we have a "Calentadora", a Mexican wood burning hot water heater (which is extremely efficient, 30 gallons heated in just 15 minutes with a handful of building scraps!!!). We use a gas generator for any power we need, power tools, or occasionally a blender or other kitchen appliance, etc. We hope to set up a DC system in our house (which we are now in the process of building) and to use our windmill for power also. We need info on this!!! We live in a WINDY, SUNNY area and we can really envision generating ALL our own power. I, myself, am expecting our 3rd child and would Love a washer and a Real refrigerator. Our propane fridge is grossly inefficient, using almost $20.00 of propane per month in the summer and it doesn't get cold enough to make ice. Those are my only complaints, no fridge or washer, but we've been doing it this way for a few years so I know we can do it a while longer.

Your magazine is REALLY NEEDED. There's a radio talk show we listen to here called KLBJ. Cathy Cronkite (yes, Walter's daughter) is the host and there's alot of talk on energy conservation. I've called in the address of your magazine so maybe you'll get some subscriptions, but I'd also like to call & give them your address as a possible guest (via long distance, of course) what you're saying is important for us here in Central Texas, South Texas Nuclear Project wants to start up this year, amidst serious protests, if people could understand the alternatives. Anyway keep up the good work, we look forward to new info. Could you send us your advertising rates?

Thanks so much-- Good Luck!!

Diane Rolfe, Fredericksburg, TX

Editor: Thank You, Diane! That one phone call brought in 45 subscription requests! That's the kind of thing we need to help spread the word.

Dear Mr. Perez,

What a super magazine! How incredibly fortunate that I somehow ended up on your mailing list, and I've enclosed a subscription form to cinch the deal. Although I'm not now a home power producer, I do have occasional need for batteries and PV panels to power oceanographic and meteorological data acquisition equipment, and being an oceanographer by training and not an electrical engineer, I've found many of the articles in HOME POWER right on target. My enthusiasm for your magazine, however, stems from my work with a renewable energy resource that is not as well known as wind or solar, but which has great promise, and that is the power of ocean waves. More on that in a moment, but first some quick business.

Having recently started my own company, I know some of what you're going through (will weekends and vacations ever exist again?). Anyway, enclosed is a check for $52.00 - $2.00 for a back issue of HOME POWER 1 and $50.00 to help - you gotta sleep!!

So a little bit about wave energy. Its first practical use for generating electricity was actually by a home power producer! In 1910, one M. Bochaux-Praceique supplied his house on the coast of France with 1 kWe from a turbine driven by air pumped by the wave-induced motion of a water column in a vertical bore hole located in a seaside cliff. Widespread commercial application of wave energy did not occur, however, until the mid-1960's, following Commander Yoshio Masuda's research in Japan on a wave-powered navigation buoy. Since then, over 1000 such generators, typically rated at 50-100 watts, have been sold by Ryokuseisha Corporation, and recently a competitor, marketed by Munster-Simms Engineering of North Ireland, has appeared on the scene.

In the mid-1970's, the industrial world's fascination with large central generating stations quickly carried the technology (on paper anyway) into much larger schemes, epitomized by the British government's development program for a 2 GWe wave power off the west coast of Scotland. Such attempts to put wave power on an equal footing with nuclear and coal-fired plants were unsuccessful. A market does exist, however, for smaller plants (500 kWe - 1 MWe) to provide energy for islands and remote coastal locations now served by diesel generators.

This export potential has led Norway, a country that is itself rich in conventional hydropower, to build two demonstration plants on the island of Toftestallen, located off its North Sea coast. The cost of the plants was shared by the national government and private industry, and they began operating in 1984-85. Kvaerner Brug's Multi-Resonant Oscillating Water Column, rated at 500 kWe, relies on the same basic principle as Bochaux-Praceique's home power plant. Major improvements have been made to the air turbine (a totally new design, the Wells turbine, originally developed under Britain's national wave program). Also rather than a simple bore hole, a concrete caisson, whose heaving water column motion resonates with the most commonly occurring wave frequencies, has been built into the island's cliff wall. Photographs in the enclosed brochure give some idea of the size of this plant.

The other demonstration plant, developed by Norwave A/S, uses a tapered channel to funnel waves into a basin in the island's interior. The waves increase in height as they travel into the ever-narrowing channel, spilling water over its sides. Continual wave action maintains a relatively constant head some 3 m above sea level. Water drains out of the basin through a 350 kWe Kaplan turbine.

The two Norwegian devices are fixed, but floating devices have also been tested throughout the world. Among these are a 1 kWe prototype Wave Energy Module on Lake Champlain in Vermont, a three-buoy 30 kWe power plant in the Baltic Sea off the coast of Sweden, and a 3-4 kWe device on the Caspian Sea in Russia. Active wave energy research also continues in Japan and Great Britain, as well as the United States, Canada, Ireland, Portugal, and China.

The wave energy resource is fairly concentrated compared to that of the sun or wind. Typical levels are 5-10 kW per meter of shoreline on the U.S. East Coast, 20-30 kW/m in California and the Pacific Northwest, and 15-20 kW/m in Hawaii and the Tradewind zones of the world. Outside of the tropics, wave power levels are much higher in the winter than summer. The wave energy resource in such latitudes almost perfectly complements that of the sun, hence the name of my company. One dream I have is to be involved in the design, construction, and operation of a community power plant that utilizes wave devices and PV panels for its renewable energy supply, with a diesel (or better yet, biomass or waste-derived fuel) generator for calm, cloudy days. I'm hoping that your magazine will put me in touch with folks who might want to be part of such a project some day, be it those who can provide technical knowhow (any electrical or hydraulic engineers out there with a love of the sea?), those who might be potential end-users of the power, or those who just think its a neat idea.

It is even possible that utilization of wave energy may be economical for the home power producer. As the technology matures, it's something I'd like to explore. My feeling right now, however, is that for best economics and minimal environmental impact, the wave resource is probably better utilized at the community level rather than by individual homes.

Perhaps of more interest to the homeowner (particularly those who have gotten away from it all and find themselves on an island without an adequate fresh water supply), is wave powered desalination. One device that is near commercial production can be installed by two SCUBA divers working out of a small boat. The heart of this device is a submerged hydraulic cylinder, which is stroked by the heaving motion of a float or buoy and pumps seawater through a reverse osmosis membrane. A small prototype has been operating off the southwest coast of Puerto Rico and produces 250 gallons per day in waves 3 feet high. An article is enclosed that describes this in more detail.

If any of your readers are curious as to whether wave power can be put to work for them, they should feel free to contact me. Likewise, if anyone has developed their own wave energy device, I'd like to hear about it. Amazingly good ideas seem to come out of grass roots efforts, and one of the best things about your magazine is that it encourages the kind of interchange that brings such things to light.

Best of luck to you, and may Home Power be the success that you wish it to be. And if the gods are kind, let's hope it can be done in a 40-hour week, better sooner than later! Sincerely Yours, George Hagerman SEASUN Power Systems 124 East Rosemont Ave. Alexandria, VA 22301-2326 (703) 549-8067

Good morning. Hope you are having a good mail day! Continuing on soldering from HP#3, pg. #44--Tried to find the conductivity of solder in my limited library, with no luck. However, the percentage conductivity of copper is 100%, aluminum is 53%, tin is 11.3%, and lead is 7.6%. And found a statement in "Principles of Electrical Engineering", Timbie and Bush, that says "the resistivity of alloys is nearly always higher than any one of the constituent metals and is always higher than that of the constituent metal of lowest resistively." Which makes solder an even poorer electrical conductor than I thought. Maybe less than 10% of copper. Can you put a number on this? Talk about connection and contact resistance is useful, even critical, and often neglected.

12 VOLT SOLDERING IRONS-- Weller makes a very good one, TCP12 field soldering iron (also available, the 24v, TCP24) 30 watt, temperature controlled. A little slug of magnetic alloy in the tip attracts a magnet closing a switch to the heating element. When the proper temperature is reached, the alloy becomes non-magnetic, and the switch opens. Tips are available in a variety of shapes, sizes, and temperatures (600°, 700°, and 800°F.). The biggest and hottest tip, PTB8, is the one I use most. I like a PTK7 (700°) for general electronics work. With the big tip it can just solder two #10 wires together. I don't have a current price list, but would guess wholesale at $30 or $40 w/one tip, and $4 or so per additional tip.

What's so nice about this iron is it cycles on and off, mostly off when not in use. Poke it on something, it snaps on and stays on. Saves a lot of power when idle, which it is most of the time while wiring something. This makes it well worth the price. Well made and dependable. Elegant.

A drawback is the 30 watt size. Fine for light wiring and electronics. Sure wish Weller made a 75 or 100 watt one like this. Since they don't, I use a small soldering copper that I heat with a torch for bigger stuff. Cheap, works well, but not so convenient or safe, and a whole lot slower. Anybody know of a high-powered 12 volt soldering iron?

12 VOLT POWER TOOLS--I've got a couple of 12 volt Milwaukee drills, a 1/4 inch, #0235, and a 1/2 inch, #1130-1. They also make a 3/8 inch, 30235. They look just like the standard Hole-Shooters except for a yellow cord and a funny plug, and they draw about 10 amps in light use and about 35 amps when you lug them down. Very good professional quality, as you would expect from Milwaukee. I use mine alot, hard. The sad part is they quit making them a few years ago. I'm told most of them were sold to utility companies for working around hot lines. Maybe folks can track down used ones. They are worth hunting for.

PLUGS AND RECEPTACLES-- Suitable connectors for 12 volt stuff. When is NEC (National Electrical Code) or NEMA (National Electrical MAnufacturers assoc.) going to come up with a standard for low voltage plug? Those cig. lighter junkers are pretty bad electrically and mechanically, but the only ones accepted as standard, as far as I know.

I mentioned the funny plug on the Milwaukee drills-It's an old straight blade type, tee configuration, (see small graphic KP) 250v., 20a., NEMA 20-2. It has good retention, low contact resistance, and most of us have never seen it before, so no confusion. They are still available for replacement use (Hubbell #5552-B receptacle, and other brands) but expensive because of limited manufacture. I've found them in the electrical piles in junk stores, enough for my own use. I think it would be a good one to standardize on, especially since Milwaukee used it for years. And if the RV market had to use them, the price would come down. How do we pressure NEC and NEMA? Who has other ideas of a proper plug/receptacle?

I'll be traveling in China for the next couple or three months, looking at technology. Does anyone have contact names, addresses, or locations of anything especially interesting? I will receive mail sent to me care of: Betty Richardson, Beijing Foreign Studies University, Box 8110, Ext. Box 70, Apt. 411, Beijing, China. To be helpful, suggestions would have to be mailed by mid-April or so at the latest. I'll try to do an article for HP on anything relevant I see (sail powered wheelbarrows? yulohs?) It would seem the Chinese, by the nature of their economy/intelligence/culture, are big on alternative energy/appropriate tech. Would it be asking too much for you to airmail a copy of HP#4 to the above address for show and tell? Will take #3 with me.

Keep at it. You ARE appreciated. But don't work yourselves to a nervous breakdown. Ain't worth it, except to us out here.

Fred Richardson, Richardson Marine Electric

Waldron, WA 98297

Dear Richard and all,

Greetings from rural Northwest Arkansas. I am writing to give you a brief rundown on my alternative energy system, and to offer a few nuggets of hard won advice.

I live in a hand built passive solar house roughly $5,000.00 away from electric lines. I purchased my system two months before the tax benefits evaporated in 1985, and have been enjoying the reasonably free 12V power ever since. I use four 40 W Arcos, mounted on a rack built from salvaged aluminum channel for $9. Storage is 750 ah--six 6 V golf cart deep cycles wired in series and parallel. The house is wired with 10 gauge two conductor wire, with seven runs to keep length and voltage drop to a minimum. Total system cost two years ago was approximately $1500.00. Module output has increased since then, and cost has dropped slightly.

There is a 5000 W AC generator which I use to run the power tools in the wood shop. Until very recently that generator also served to pump water uphill to a 100 gallon storage tank for gravity feed into the house. But the pump unfortunately froze and broke about two weeks ago, and I am currently in the process of installing a 12 V DC pressurized system. I may report on that system if it works out well. Also under construction is a 5 hp 12 V DC generating device. Your last issue's information on the controller was greatly appreciated.

Everything in the house is 12 V, including color TV and VCP (player, not recorder), computer and monitor, stereo, incandescent and fluorescent lights, home-made ceiling fan and blender, soldering iron and tiny vacuum.

Solar hot water back up is Aqua Star demand-type propane hot water heater. Inexpensive and wonderfully efficient. This summer I took the plunge and installed a SABIR propane refrigerator. Frozen daquiris for the first time in years! The hot water heater, my tiny four burner stove, and the fridge should run for two years on the two hundred gallons of propane now in the tank.

My home situation is somewhat unusual. I am a Physical Therapist and commute 30 miles to my clinic. I work there Monday/Tuesday, and Thursday/Friday, so I am home only Wednesday, Saturday, and Sunday. Because of this infrequent use of my system, I have ample energy for my needs. However, I discovered the edge of the envelope this winter when after fifteen days without sun, and after numerous long nights playing new Infocom computer games, I drained the system voltage to the point of shrinking image on the computer monitor. I am constructing the 12 V generator to avoid future energy shortages.

Here are a few tidbits of information.

INCANDESCENT LIGHTS. Best and brightest: quartz-halogen bulbs. Cheapest are 20 W 12 V JC Whitney at $4-5. Don't spend the money for the fixture they sell, just use regular lamps. The bulbs have really unusual bases, so I solder a couple of wires directly to the bulb base, and to a screw mount base from a broken 110 bulb. Ten minutes of work, and cheaper than $7-9 adaptors. Clean the bulb with alcohol to get off finger oil before turning it on.

In my house, I have used RCA-type phono jacks for my electric plugs and sockets. They are cheap, especially in quantity, and are relatively easy to wire. They are just a bit delicate, however. Emerson makes a 12 V Video Cassette Player (not recorder). It's inexpensive ($165 at a local Wal-Mart) & sturdy.

I take exception to your advise to go with a 110 V computer.

If one is not absolutely wedded to the idea of the MS/DOS environment, there is a marvelous alternative in the Laser 128. This Apple-compatible computer that is rugged, inexpensive, and operates marvelously on 12 V. It is available through various mail order outlets in its standard version for as low as $365, or in its souped-up 128EX version with extra memory capability and faster clock speeds for $495. I have carried mine back and forth over rough roads in my truck twice a week for almost a year and a half with little problems. Check a recent Apple-type magazine for ads.

The other optimum 12 V computer is the Apple IIc. Both it and the Laser just need to have a 7 pin DIN plug input. Manuals give the wiring configuration. These computers will pull no more than 1.5 A, on the average. More disk access will up this average somewhat. A monochrome monitor may use between 1 and 1.5 A. This isn't much drain.

Some computer monitors operate on 12 V. I have seen ads in the surplus catalogs for 12 V monitors for as little as $25.00. And some 110 V standard monitors actually operate on 12 V circuitry. The Samsung monochrome 12" monitor I use is a 110 V device. On inspection of its schematic, it was discovered that its circuitry actually utilized 12 V via a step down transformer. I made two small solder connections, and Voila!, 1 12 V/110 V monitor. The only problem is a 12 V printer. I know of only one, the DICONIX, made by Kodak. It costs an arm and a leg, so I don't have a 12 V printer. I'd love to hear of an alternative.

Finally, here are some useful references: Best and foremost if you are going to do anything with DC electricity is Michael Hackleman"s "Better Use of... Your Electric Lights, Home Appliances, Shop Tools--Everything that uses Electricity".

JC Whitney's Catalogs. Get on their mailing list and especially watch the semi-annual clearance catalogs. Quartz halogen bulbs are cheapest during clearance sales about $4.00 each. Also occasional deals on alternators (I just got 55/60 amp rebuilt $19.00), 12 V pressure pumps, & lots more.

Electrical Independence Booklets. Available from some alternative energy dealers. Good info on panel mounting, making a DC generator, converting appliances, etc.

Various Alternative Energy catalogs. Spend the money. Many are packed with information and it pays to shop. The money saved by comparison shopping will amply repay the investment.

Surplus electronics catalogs are a storehouse of dc whatamacallits and thingamabobs. Fans, motors, relays, plugs, jacks, computer parts-- you name it. And all cheap, cheap, cheap. If you can use what they've got, you'll save a bundle.

I am sorry to have gone on so long. But maybe an idea or two will be of worth to somebody. If there is some small part of this that you would like to use in your newsletter, be my guest. And if not, I was glad to tell you a bit about my situation, anyway. I'll be glad to answer questions if people include a stamped, self-addressed envelope.

Rick Goodie

RT5 Box 137

Huntsville, AR 7274

GREAT MAGAZINE. Informative, instructive, and a great source of all around information on alternative energy sources. I would gladly subscribe to this magazine should it become nationally circulated. I also have friends interested in alternative energy sources. Please send an extra copy of Home Power.

Thank You, Brad Hunter, Los Angeles, CA

Editor: We do have national circulation and we are also building an international circulation. Tell your friends to fill out the extra subscription form we've provided in each issue or simply write their request with name and address on paper and send it to us. We will be happy to add their names to our mailing list.

Have read and reread all three Home Power issues. They are GREAT. Although our underground home is served by public utility power, our belief in solar power is such that we have two distinct and separate Solar AE systems in operation.

An AE Solar powered stand alone system furnishes AC power for all tools, lights, etc. in our furniture refinishing workshop. An AE Solar powered Grid-Tied system is installed on the house which provides a portion of our domestic electrical needs. Currently up to 5KW of utility quality 240 volt AC power per day has been generated and fed into the public utility grid through a separate meter. While systems of this type currently have a fairly long payback, it does demonstrate that AE can be integrated into homes that are served by public utility power. As non-renewable resources continue to dwindle and utility costs continue to increase, systems of this type will become more popular.

Warren & Bobbie Webbeking, Prescott Valley, AZ 86314

Hello, we've been homepower people for a decade, and as I'm too tight to spring for a good book, I've based my "system" on rumor. I'm sure you can help civilize me. We have 2 panels, 5 mismatched batteries, our new house under construction (hah, 4 years now) too many children, and a death wish.

Please send #1 if you have any left. Enclosed is the only 2 dollars we have left in the world as our fishing boat just sank.

As much as I abhor nostalgia, your rag brought an early seventies tear to my crowsfeet. Please no articles on channeling & crystals.

Love, Daniel, Daphne, Orla, Kila, Cat, Mako & animals

Barbarian Enterprises, Monhegan Island, ME

I presently receive about 15 magazines, but this was the first issue of any magazine that I read from cover to cover, including ads. I have included a small donation. Could you please send me issue #1. I would like to see an article on the care and feeding of batteries and something on how to start small and gradually build up to a full blown system.

Alfred Judd, Gardnerville, NV

Keep it coming! Please get advanced info on 12 volt audio. Tascan (TEAC) makes a 12 volt Mini Studio 4 track cassette deck for musicians, I have one, it's Great!

How about an article about hooking up power boosters to boom boxes, 12 volt stereo, etc. for us backwoods, sun powered rock and rollers. Great mag, best of luck. I love it!

John Condon, Decorah, IA

This is the first publication I have ever read that has good, useful information on alternative energy. I have stacks of magazines & books on the subject that seem to be written by people who have no first hand experience in the field. Thanks for the magazine we've all been waiting for!

P.S. I recently purchased 2 Kyocera PV's to compliment my single ARCO panel I've had for a year. And I'm luxuriating in lots of 12 VDC fluorescent light & super running AC appliances with my shiny new Trace 612.

John Blittersdorf, Pittsford, VT

I'm very interested in solar & wind power systems. I would like to get a local group together to discuss different ideas and how these systems work.

Brian J. Lea, RT1 Box 375 H Valley Rd., Honor, MI 49640

What a wonderful effort. Thanks! I like your philosophy and your intentions. Perhaps an extension of ideals about energy could parallel the meta-physic: that energy gained must be exchanged. Don't knock yourselves out on a monthly that will transform you into burnouts and us into blase. Make it fuller, less often, and by fair exchange to the receiver. How about... Quarterly for 5 bucks with lots of space for specific or site responses. I mean really! Get a charge for your voltage.

Furthermore and in any case, we here in the oldest hills in the world (Grandfather Mtn.) are glad to see you're there. Lots of us are.

Ya do layout on a Mac, you rascals!

Mark Tomlin, Boone, NC


We try our best to directly answer all your questions. Please remember that we are limited by our own experiences. If we don't have the direct personal experience to answer your question, we won't. We'll print the question anyway and hope that a Home Power Reader will have the experience to answer it. So this column is not only for questions to Home Power, but also for answers and comments from its readers. We try to answer as many questions as we can. Fact of the matter is that for every one we print, there are about 10 we don't. It's a matter of space. Hopefully, we will be larger soon and can deliver all the fine material that forlks have sent in. Thanks for your patience-- Rich

What about thermovoltaic energy? Can electricity be made from the heat of a wood stove as rumored?

Ken Zimmerlee, Wauconda, WA

Yes, heat can be converted directly into electricity by a process known as the Peltier effect. Hot to cold differential causes free electrons in some very special materials. This process is similar to the photoelectric effect that's employed in PV cells. I've heard rumors that there are prototype Peltier effect generators working, but that longevity and efficiency are still problems. Anyone using these devices, please write Home Power central and let's set up an article about direct heat to electric conversion. The wood burning stereo has long been a fantasy of ours.

Will a 10 amp trickle charger work to charge deep cycle batteries off of a 120 volt home circuit?

Patty Dillberg Santosha, Kaunakakai, HI

Sure, if you leave it on long enough. Ideally, it's good if the charger can deliver at least a C/20 rate to the battery. However, charge rates as low as C/100 can be quite effective at recharging and even equalization, if they are left on long enough.

Many of my appliances have adaptors which go from 120vac to 12 or 6 VDC. When calculating my power consumption do I consider these appliances as 120 vac or 12/6 VDC. Please address this issue for me as I have not been able to locate this information anywhere as yet. Thank You.

Rolf Mueller Plainfield, VT

If you are using the 120 vac adaptor, then calculate its power consumption as a 120 vac appliance. If you have converted the appliance to direct DC use, then treat it as a DC appliance. Many small appliances can have their efficiency greatly increased by putting them directly on DC rather than using their ac adaptors.

We built a small (4 ft.) overshot wheel connected to an old shallow well pump that our creek powers 9 or 10 months a year at 1 to 2 gallons a minute. We would like to know if a car alternator could be hooked up to the wheel in the winter to trickle charge a battery bank?

Stephen & Cathy Posavatz Hornbrook, CA

Yes, this can be done. The problem is that most alternators like to run at high RPM, while your water wheel travels at very low RPM. In many cases, the belts and pulleys (or gears)

required to raise the RPM of the system waste so much power that the system barely produces enough surplus energy to recharge batteries. I've seen setups like you described which can produce about 1 to 3 amperes at 12 VDC, and this amounts to around 400 watt-hours daily.

I would like to find out how to rebuild or recondition lead acid batteries. Do over the counter chemicals do anything they claim? Do they prolong the life of new batteries? Keep up the good work.

Frank Forseilles, Dolan Springs, AZ

We'd like to have this information also. I've no direct experience with the chemical battery additives. Help! Home Power readers with this knowledge, please check in.

Can the voltage meter circuit (HP #2) be adapted to a 24 volt or higher system? Can you show us one to measure AC current also? That would be a great help for me and many others I am sure.

Robert Wise, Showlow, AZ

The meter circuit in HP#2 will work well in 24 VDC systems with some minor changes. Use the original schematic, but make the following changes. On the voltage divider feeding pin 5 of the LM 723, change the top resistor from 10 Kw to 51 Kw, change the pot (R1) from 2Kw to 5Kw, change the lower resistor from 22kw to 24Kw. On the series resistor string feeding the plus side of the meter, change the 3.3 Kw resistor to 9.1Kw. On the resistor connecting pin 11 of the LM 723 to Vcc, change it from 1Kw to 2Kw. Adjust R1 so that the test point measures 22 VDC. Adjust R2 until the meter reads properly. The finished meter will start reading at 22 VDC and will be full scale at 32 VDC. This is the operating range for a 24 VDC lead-acid system. Circuits for measurement of current, both ac and DC will be forthcoming in future issues.

I have a Honda 350EX. Any suggestions on how to quiet it a little more? Can a muffler/exhaust port attachment be put on safely to extend the exhaust for diversion of gasses & quieting? Does this cause any problems with back-pressure in the exhaust manifold?

Hal Zimmer, Issaquah, WA

First thing to try is your Honda dealer. In many cases they make extra quiet mufflers for their models. You can use the muffler/exhaust port attachment to attach a better home made muffler. The trick is not to hang a lot of weight on this port, but to brace the muffler assembly elsewhere. Allow for expansion and contraction of the muffler assembly.

Excellent on battery storage in last 2 issues. I would like a clarification: you seem to imply with the limits of a C/20 charge rate and reliability constraints of internal resistance that large autonomy - 10 days or more - is impossible. Am I missing something?

Steve Smith Swanlake, ID

Long term energy storage in lead-acid batteries is not impossible, but it is inefficient. Consider that the high antimony, lead-acid batteries most suitable for home power use have a self discharge rate of about 6% of their capacity weekly. A pack that stores energy for 4 weeks would lose about 25% of its energy to internal action. Nicad systems do about 3 times better. We size our engine/PV systems with at least 4 days of storage, but with no more than 10 days storage. It is more cost effective to run the engine during expended cloudy periods than to increase the capacity of the battery pack.

So far, the generator seems to be the best way to bring batteries up to peak charge. I would not like to be dependent on gas, so would you have any advice for bringing the batteries up to some semblance of peak charge?

John Roshek Weed, CA

You can completely fill your batteries with any energy source you have available. A gas generator is cheap and its power is available when we want it. Oversize your PV system to produce about 10% to 20% more energy than you're consuming— this will keep your batteries in tip top shape. Batteries love Hydro inputs because they are constant, so develop any Hydro potential that you may have. We are all doing all we can to wean ourselves of fossil fuels. Right now we are forced to make some hard decisions, basically due to the cost of PVs. As PVs become even less expensive, we are looking forward to kissing our engines completely goodbye.

Two things I'm interested in - low power water pumping (shallow well & using a pressure tank) either 12 VDC or 115vac and 12 VDC color TV's. Is there anything made with a screen larger than 12 inches?

Lisa Reynolds Pearson, WI

We are working on a PV powered water pumping article right now. Contact Flowlight Solar Power, POB 548, Santa Cruz, NM 87567, and ask Windy Dankoff about his PV powered pumps and PV powered booster pumps. They work, are well made, and are worth more than he charges for them. In terms of 12 VDC color TVs, the ones I've seen are all small (<12 in.). Anyone out there using larger screen TVs on low voltage DC?


Marine catalogs have a variety of 12 VDC stereo equipment, i.e. Cybernet #CMS54050 65 watt booster amp & 5 band graphic equalizer. P.S. I also dropped a note to D.C. Tamm.

Walt Cunningham Port Bailey, AK

All right, a Home Power reader delivers the info! Thanks for sharing. If anyone has answers to the questions seen in this column, please feel free to contribute. We do the best we can with what we personally know, but we don't know it all by a long shot.

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Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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