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data generated according to the wind industry standards, so there is a little room for error in my numbers. I will include two numbers for the WT 2500, a number that uses my actual production figures, and a number that extrapolates the data to what it might be like if it actually gave me 2,500 watts of peak output. Sincerely, Michael Klemen • [email protected] www.ndsu.nodak.edu/ndsu/klemen

Mike, Your statement that"some manufacturers can be generous in stating their power curves," is an understatement. And I agree with you wholeheartedly, and with your tactful use of words. I have taken a stab at projecting outputs of all the turbines listed in A&O '02. It's on Home Power's Web site as an appendix to the article.

Please note that I did not"estimate" the outputs of some of the turbines in the way that you apparently took it. And they are not my estimates; they are numbers supplied by the manufacturers.

In the case of Proven, I tried for several weeks to get monthly output numbers. I was eventually supplied with an annual energy output curve. When I persisted, I was told to estimate the numbers I needed from the curves. What I did was calculate monthly outputs from the curves they provided.

I also agree with you on your comparison of the Proven and the AWP While I have not monitored the outputs of either machine, I have thoroughly disassembled both the AWP 3.6 and the WT 2500. Based purely on greasy observation, the Proven alternator appears to be a more efficient design. However, I don't believe that either will deliver the outputs the manufacturers supplied me with. I believe that the AWP is underrated, while the WT 2500 is overrated.

I would also like to compliment you on your work in verifying wind turbine outputs. I think it's great that you are gathering output data correlated to your wind speed. It would be terrific if we had more folks with the ability to do this type of turbine performance verification. Now, if we can only find a way for folks doing this work to be paid. Mick Sagrillo, Sagrillo Power & Light, E3971 Bluebird Rd., Forestville, WI 54213 • Phone/Fax: 920-837-7523 • [email protected]

Safety & Lawyers with Grid-Tie

Dear HP, I've been following your ongoing discussion on guerrilla solar with great interest. I'm utility intertied with 1.2 KW of PV, so it doesn't really apply to me, but I did need to jump through all the hoops with our local utility, Arizona Public Service, to do the intertie, so I totally understand the motivation for guerrilla tactics. The response by Joe Schwartz to the letter "Puzzled Over Net Metering" (HP90) makes a very good point—utility linemen work under hazardous conditions all the time and know how to protect themselves. Since we did our intertie, we've had at least ten outages; our visible disconnect switch has never been used. I put a small piece of tape on the switch handle that would break if it was thrown, and the tape is still there. Why? Allow me to relate an interesting story.

I did all the wiring on our home, and learned to respect electricity at an early age. My dad, who was an electrician, taught me everything I needed to know. On one occasion I needed to do some rewiring, so as always, I turned on a light in that circuit, went to the panel and turned off the breaker, returned to the room to find the light off, as expected, and proceeded to wire.

Needless to say, I was surprised to get a jolt of AC while replacing the outlet! Turns out that sometime between turning on the light and returning to the room, the bulb burned out. And, obviously, on this same occasion I had turned off the wrong breaker. Lesson learned.

Now I always put a meter on the wires before touching them. Any lineman that does otherwise is risking a far larger hazard, given the voltages they routinely work with. At 480 V I wouldn't even trust a visible disconnect switch! Common sense field practices make the visible disconnect switch unnecessary (as do modern inverters). I think the utilities know this. Certainly their linemen do. I suspect it's the lawyers that drive this requirement. Any linemen readers out there care to corroborate this? Dan Heim • [email protected]

Civic Hybrid

Mr Perez, I have been reading your magazine off and on for about six years now and have only dreamt about alternative energy. My wife's car has 198,000 miles on it, and we figured we could use a new one. We have been watching the hybrid auto developments for quite some time, and were pleased to see the Honda Civic recently introduced. We test drove one on Saturday and bought it. Fifty mpg is going to be sweet.

On the plus side, the car is a full-size sedan. Other than two gauges indicating battery charging (such as during braking) and indicating that the electric motor is assisting the engine, and a blinking light when the engine shuts off at a red light, the darn thing feels like an ordinary car. At US$20,000, it is not even really all that much more than a regular Civic, especially since we get a US$2,000 federal tax credit, and considering that the regular Civic gets 35 mpg at best. We are going to do a lot of smiling when we pass gas stations. We pick it up on Wednesday. Can't wait!

Later that week...

So far we love the car. With air conditioning on and four adults onboard, we were getting 47.5 mpg. We managed to top 50 mpg on a trip to Hartford with two in the car. I recently checked out a Prius up close. Not to put those people down (because it was the first four-seater available), but the Civic is definitely a much more luxurious and comfortable car for the same price and about the same fuel economy. You wouldn't even know it was a hybrid until you look close, whereas the Prius has an "alternative" feel about it. This car is definitely going to change things. Friends of ours who rode in it were impressed with the power, comfort, and technology—like turning off three cylinders when coasting to reduce drag on the engine, shutting off at stops, etc. Cheers, Jim Kasper, Hamden, Connecticut • [email protected]

Collective Voice

Renewable energy (RE) is too good of an idea to let go. Widespread use of RE practices will have a profound effect on how we humans live and interact with each other. As individuals, we can take charge of our own energy needs, using nothing more than our ingenuity and our bare hands. It is entirely possible to live a thoroughly modern life, but without the negative drawbacks of creating pollution and furthering petrochemical dependency.

Breaking the vicious cycle of our societal oil habit will have long-term consequences on the world geo-political stage as well. Every person who says "no" to what the corporate utility complex tries to force on us is someone striving for a better answer, a better life, a better future. Home Power is among the first whisperings of this growing collective voice. Bill Chellis, Seymour, Connecticut • [email protected]

Use It Up,Wear It Out, Make It Do, or Repair It!

The mantra for environmentalists seems to be "reduce, reuse, recycle." I think that there should be one more— repair! A few weeks ago, the dryer in my house stopped drying my clothes. I knew that the problem was the heating element, because for a few weeks, I had not been getting that warm, huggable feeling when I took clothes out. My clothes were in there spinning around in circles getting quite dizzy, but never getting dry.

One day (after I had run out of clean clothes), I took the back off the dryer and figured out where the heating element was. I took the element out, and took the numbers off of it, thinking that I could go to the local hardware store and find this pretty common replacement part. Wrong!

I went to the local monolith that has extinguished all life from every other "home improvement" center in the last several years. It was fairly easy to locate the appliance department, but quite impossible to find assistance. I eventually stopped the third smock-wearing individual who was walking by on some task far more important than assisting a customer. "Where might I find an element for a dryer?" I asked. His response was, "There are several elements in a dryer." He then proceeded to tell me that they had a limited parts selection. Then he tried to sell me a new dryer.

Dryers are not very expensive (though they do cost much more than the 50 feet of rope that I would have needed to make a clothesline). It would have been easy to buy it, have it delivered, and have them cart away the old one. (I would have been doing my laundry later that same day.) Unfortunately for the inept sales guy, I have this misconceived notion that durable goods (like home appliances) should be durable and repairable, not disposable.

If you are (un)fortunate enough to think the same way, and you have a problem, www.repairclinic.com is a great Web site that I found during my quest for parts. If you think that such a complex subject as which screws should be turned, and which way to turn them is beyond your grasp, you are wrong! The only tools I needed were a screwdriver and a pair of pliers. There are fantastic troubleshooting charts and step-by-step directions, right here on your computer waiting for you. Matt West, Reston, Virginia • [email protected]

Proud & Thankful

Back in 1995, I was in Dallas, Texas, for a seminar, and happened to go to a bookstore just to browse. I came across your magazine on the shelf and bought it. After reading it over and over, I asked myself, "Can this really be done?" I spent the next year researching, took SEI's PV Design & Installation workshop, and then took workshops with MREA. I designed, bought, and installed my own 1 KW PV system with a 900 watt wind generator. It's my baby and I am proud of it. All thanks to you, HP. You have answered my several email messages with the best of advice. God bless you all, God bless solar guerrillas, and may the sun continue to shine. Doyle L. Lonski, Antioch, Illinois • [email protected]

Computer Security

Dear Home Power, There is a serious flaw in your article about computing in a solar house in HP90. The author says, "We added a D-Link wireless router (Model DI 713P, US$140, 7 watts) that gives us the ability to use the laptop almost anywhere in the house. It also connects the two computers together, and provides good Internet security from hackers. Incidentally, software can provide good protection also, but it's not as good as the hardware solution in a router."

Software (a firewall) would be better than a router. The D-link only opens and closes ports, and usually it leaves ports open. If you use a firewall, the software can usually tell when your ports are being scanned, and block access to some hacks. A wireless router will let hackers have their way with selected ports and allow them to open others. So where is this wireless system? I wouldn't mind setting up a spam server on the computer (grin). Edd Thompson [email protected]

Hi Edd, Your comments on security are probably correct, since the software is continually getting better. I take no credit for expertise in this area. My actual experience is limited to setting up my own network. I do try to keep up with the research and expert opinion from reputable sources, like PC Magazine. And over the last couple of years, what I said in the article seemed to be the message. Now it appears that the best overall advice is to have both hardware (router) and software solutions in place, as well as up-to-date antivirus and even anti-spam software. Security is a continual challenge.

When I wrote those couple of sentences in the article, I was sorting out whether to even mention security issues, since that was not the focus of the article and it was getting kind of long. I finally decided to make a brief mention, just in case some of the readers were not too aware of the need. In hindsight, I might better have said, "by all means do both; and keep your security software up-to-date."

Of course, the best security is having the system, or parts thereof, turned off when not actively computing. We do it mainly to save energy. But if the radio and/or router are off, or if the computer is off or in hibernation, somebody can knock, but they can't come in.

I recently found a good basic guide with lots of informative links at www.firewallguide.com. They look to be impartial, but do derive income from linked equipment sellers. A particularly informative link on wireless security is www.practicallynetworked.com/support/wireless_secure.htm Aloha, John Bertrand • [email protected]

Hi Edd and John, There are some excellent and well-performing hardware firewalls out there, and some routers also with good firewalls. While cruising around Internet security sites, I happened across some that will actually simulate an attack on your system for the purpose of reporting back to you any insecure situations that might exist in your hardware or software firewalls. Check out www.securityspace.com for both free and subscription security checks. For very basic but good tests, and good and interesting info, check out Shields Up at www.grc.com. The site www.hackerwacker.com also has both free and subscription security checks. Practice safe computing—use protection. Michael Welch [email protected] com

Insurance for PV Grid-Tie

Back on February 23, you sent me an e-mail concerning my efforts to erect a wind turbine at my home. I gave up on that and had Andrew McCalla of Meridian Energy Systems in Austin, Texas, install a set of solar-electric panels on my roof instead, which worked beautifully for one day. We thought we had sufficient permission, but the Kerrville Public Utility Board (KPUB) came and shut us down and put their padlocks on the control switches. We (Andrew and I) were told that they would give us a list of their requirements so we could operate the system. They said that their main concern was electrocution of their staff through malfunction of the inverter, a Sunny Boy, which is certified to meet all the IEEE and UL anti-islanding requirements, but KPUB was not satisfied.

Six weeks went by and suddenly we learned that the KPUB board had passed a resolution (why was it ever needed?) to permit distributive generation—selling electricity back into the KPUB grid. Now I have been presented with a contract to sign, one provision of which is that I maintain US$1 million liability insurance policy payable to KPUB. I am fighting that at the moment. I am even considering in the meantime asking that I be able to connect the panels on a nonexport basis, which could at least save some money and not infect their precious grid.

Has your magazine ever published an article on this insurance issue? If so, would you send it to me? Or if not yet, would you consider running one? Andrew and I could write you one hell of an article! Regards, John Miller

Hello John, Sorry to hear your sordid tale. Unfortunately, we've heard it before. We've never published an article that specifically details insurance requirements of grid-tied RE

systems. Many states address the insurance issue in the text of the net metering legislation. When we were moving Oregon's net metering legislation through the state House of Representatives and Senate, we kept a close eye on the text that excluded any additional insurance requirements for grid-tied systems, making sure it wasn't altered.

The first thing I would do is thoroughly review Texas' net metering legislation text. Is insurance detailed in the law? Is KPUB legally exempt from the legislation? The information I have states that both investor owned utilities (IOUs) and rural electric co-ops (RECs) are included under Texas' net metering law.

We'd love to see an article on your system and your policy struggles. It's exactly what we're looking for. We hope it has a happy ending. You're in good hands with Andrew on the job. Please let us know if we can lend a hand, and keep us posted! Joe Schwartz • [email protected]

Payback Distortion

I agree with many Home Power authors and readers that there's an enormous amount of government interference in the energy market, which destroys the ability to make a rational economic calculation of the payback of RE. Such government interference includes: tax credits for RE users, corporate welfare such as grants for RE technology research and subsidies for established energy providers, defense spending to colonize the Middle East, regulations prohibiting the unusual, price caps, prohibition of competition, speculation, and sales to the market.

These distortions in the market destroy the validity of the price system, a beautiful thing wherein all the minds on the planet cooperate to make the world's aggregate best guess at how to produce the amount of energy people want with the fewest costs.

But many people looking at renewable energy for the first time want to know, "What's the payback?" I would love to see a stab made at constructing a straight answer to the payback question, by detangling the elaborate web of forced payments and prevented choices. For instance, if the U.S. energy companies stopped trying to get the U.S. Army to colonize the Middle East so they can run an oil pipeline through it, how much would we save from the defense portion of our federal taxes? Would this be offset by higher prices from OPEC? Would voluntary OPEC sales made at voluntarily agreed upon prices have more moral legitimacy?

If all nonsafety barriers were removed from utility intertie, all residential visual aesthetic zoning rules were eliminated, and people believed the rules would stay the same for 30 years, how much long-distance energy transport would be replaced by local RE generation from rooftops, backyards, and vacant lots? How much would we save from eliminating long-distance electrical transmission losses? How much resistance to accidental power disruption would we gain by decentralizing generation? Would we transport natural gas long distances to neighborhood fuel cells instead of transmitting electrical energy, because the transmission losses would be lower?

The payback question is a very good one, and I believe it deserves an attempt at a straight answer. Brian, Massachusetts

Hi Brian, Indeed it does. How about an article on the subject after you do your research? Regards, Ian Woofenden [email protected] com

How-To

I have purchased Home Power sporadically from newsstands during the last five years on impulse. This impulse was triggered by the practical nature of the technology featured in real world applications. To read almost any Home Power article dispels the myth that RE is available only to those with exceptional technical experience or large monetary resources. Many publications and organizations promote "We can all make a difference," but Home Power shows how individuals everywhere are actually and practically doing it. Thanks for providing the forum for sharing real RE information. Jim Vonderwahl [email protected]

Saving with Battery Cables

Hey, Richard.You did a great piece of work in the article, "Make Your Own Battery & Inverter Cables" in HP89. It showed us a number of things:

1. We can do this! It isn't rocket science.

2. Good connectors don't have to cost an arm and a leg.

3. Good cabling can be tailored to each situation; long enough, but not too long, and they can be neatly done. Personally, I like the way the finished connector is sealed from contaminants.

You said, "It's a lot of work to make these cables." I disagree. It may take a little more effort, but the end product is better for the job and the long haul! The effort is really an investment. 73, Herb Lacey, W3HL • [email protected]

Grid-Tied Wind

Dear Home Power, I bought the June/July issue of your magazine with the idea of seeking out a roof-mounted wind generator to feed electricity back to the grid. I was happy to come across reader Gary McBurney's letter in Q&A regarding this subject, but was equally disappointed to find out that there is no current solution.

This seems like such an obvious method of simple electricity generation, why have manufacturers not developed a modern day solution (Mick Sagrillo mentions there used to be inverters that could do this)? I too, like Mr. McBurney, don't have a lot of money to spend, but would nevertheless like to contribute my part, and wind generation is appealing to me. Are there any solutions on the horizon? Can manufacturers and utilities step up and find a cooperative solution? Regards, Christopher Thale, Greenwood, Indiana

Hello Christopher, Yes it does seem like there should be a simple, inexpensive solution to grid-tying a wind system. Why doesn't it exist? Simple economics. Twenty-five years ago, the leading technology for home energy systems in the U.S. was wind generators. There were at least two manufacturers of utility interactive inverters. Both were batteryless, SCR inverters. Some were even used on very early PV systems. They worked, more or less. Today they're considered old technology.

Fast-forward twenty years, and wind energy has taken a back seat to PV as the leading technology for home energy systems. The main reason is the intrinsic simplicity of photovoltaics. The grid-interactive inverters available today are designed around photovoltaics as the "prime mover," not wind.

So what's the solution? Make your needs known to the inverter and wind generator manufacturers. Some movement is happening, but it is slow. For example, the 10 KWBergey Excel uses a Trace Technologies Grid-Tec utilityintertie inverter. This inverter was specifically designed for the Bergey Excel, and is not available for any other wind system. In addition, the Jacobs 31-20 comes with its own SCR driven, grid-tied inverter. Like Bergey's Grid-Tec, the Jacobs inverter is designed for use only with their wind generator.

SMA, the makers of the Sunny Boy grid-tied PV inverter, have a grid-tied wind version they call "Windy Boy." It is in use with the Proven WT 2500 and WT 6000 in Europe. Unfortunately, this is a 240 volt, 50 Hz unit. Proven says they can provide 60 Hz chips for use in the U. S., but to date, no one has sold or bought one of these. Maybe if some of the inverter manufacturers out there see these letters, it will stir some movement towards the development of a batteryless, grid-tied inverter for wind turbines.

The Advanced Energy Incorporated (AEI) grid-intertie inverter is another option. I personally have not seen any wind systems with these inverters on line. I'd really like to hear from some dealers and users about their experiences with an AEI grid-tied inverter/wind turbine combo.

On another note, I'd like to discourage people from putting wind turbines on roofs. The problems with this practice range from little or no wind at the house roof to increased turbulence around the top of a building, both of which severely cut into production as well as turbine life. There are also structural considerations, since houses were not designed to handle the harmonic vibrations set up by the generator itself as it generates electricity. These harmonics are normally unheard vibrations, but when a wind turbine or its tower are attached to a house, they are transmitted through the structure and make audible noise inside the house itself. Virtually everyone I know who has attempted mounting a wind genny on their roof has complained about the noise, subsequently relocating the wind turbine to a real tower, where it belongs. Mick Sagrillo, Sagrillo Power & Light, E3971 Bluebird Rd, Forestville, wI 54213 Phone/Fax: 920-837-7523 • [email protected]

Instant Renewable Gratification

I have been interested in RE for quite a long time, ever since I was a young'n and heard about biomass and PV panels. So when I got turned on to your magazine about a year ago,

I started downloading issues right away. After I moved to the mountains and ended up with lousy bandwidth, I got a subscription. So now I'm getting paper copies to thumb back and forth through, and I get to support you guys. Now all I want is for the two months between issues to go by faster. Barring that, I ordered all the back issue CD-ROMs (1-7) that you have. Those should be able to satiate me for a little while. But now I have to wait for them to arrive, but only for a short time. Damn my need for instant gratification. So as you have probably guessed, I am quite pleased with your little subversive, new communist rag. I am looking forward to more articles on fuel cells and biomass. Other than the wait, it's all just grand. Keep it up, just make it come more often. [email protected]

Only for the Rich?

I think the education that you offer to people is absolutely wonderful and gracious. But I began to cry when I realized that people in my income bracket will never afford the materials and educational tools that it takes to attain this sort of liberty. If people had the income, why wouldn't they choose wind turbines, solar-electric panels, and all the batteries and little knobs, and inverters? And why not a small piece of land somewhere where they could grow their own vegetables, and get milk from old Bessie, and dry their own food, and have a smokehouse, etc.? I'm sorry, I have always strived for these things and have not made progress because of the expense. It is just so sad to realize that only a select few will benefit. Lana Willis

Hello Lana, It is simply not true that using solar energy is only for the rich. I bought my first PV module when my annual income was below Us$4,000. It's a matter of where you spend whatever money you have. Also, many of the concepts involved in using solar energy cost nothing at all— energy efficiency can be as simple and cheap as turning off unused appliances.

Some solar energy equipment is very inexpensive. We publish a book called Heaven's Flame that shows how to build a simple solar cooker out of dumpster divings. Total cost is less than US$10, and it cooks whole meals! Consider a clothesline—totally solar powered, and it costs only a few bucks for a length of rope.

While solar electricity for an entire average American home is expensive, not all homes are average. PV systems are going in at a rate of tens of thousands per year in Africa. These systems involve only a couple of PV modules and cost less than US$1,000 each. They provide lights at night and communications, such as a radio or a small TV. It's all a matter of proportion. Richard Perez [email protected] com

Missing Capacitor

In the HP90 Letters section, page 150, under the title "How To Fix that RFI Problem," two capacitors are referred to with values of 470 and 0.01 microfarads. Unfortunately, the diagram at the bottom of the page only shows one capacitor. What happened to the second capacitor? This scheme will solve a big problem for me. Thank you for considering my question and please keep up the good work in your magazine. I thoroughly enjoy my subscription. Alan Turof

Hello Alan, The second capacitor (which may not be necessary in most cases) is wired in exactly the same manner as the first one shown. The small capacitor (0.01 micro farads) acts a short circuit for RF energy (anything above about 1 MHz), and the larger 470,000 microfarad capacitor acts to reduce DC ripple on the line (very low frequency). Both are wired from plus to minus. Be careful with the larger capacitor, since it's an electrolytic capacitor and polarized (has a plus and minus side), while the small cap is nonpolarized. Holler if you need more info. Richard Perez • [email protected]

Comments on Three Articles

Dear Home Power, I enjoy your magazine, especially the Aug/Sep 2002 issue where I found articles on three little projects I have already done myself! Some thoughts:

The white LED flashlight could be made brighter with LEDs available from Digikey in Minnesota • 800-344-4539 • www.Digikey.com. They now offer two, 2,300 mcd white LEDs, #CMD333UWC-ND or 67-1604-ND, for US$3 each, with large-quantity discounts. However they do charge shipping, and there is a US$5 charge for orders under US$25, so this is only a good alternative for somebody who might want to make several.

John Gislason's approach is unconventional because it does not employ a current-limiting resistor in series with the LED, but he is right, it does work fine with a battery power source. It is easier to position the LED for focusing if you remove the circular base ring with a mototool or a hand file.

Homebrew yagi antennas perform great, and are cheap! Another construction method is to make the body out of PVC pipe and connectors, with plain old wire for the metal parts (where Bill Layman used a cut-up multiband yagi). The same dimension rules apply. In this case, as he points out, the tuned frequency will be narrow because of the wire's small diameter.

The Kill-a-watt meter that you review fills an important need, but there is a cheaper way! Clamp-on ammeters read current through an inductive loop. The cheapest source I have found for these is Harbor Freight Tools • 800-423-2567 www.harborfreight.com • Item 42397-1NTH, US$19.99

To use the meter, you need to clamp around a single conducting wire. This is very easy to do after buying something like a short air conditioner extension cord that has flat conductors, and separate off one conductor for a few inches with knife. If you accidentally cut through copper, cover with electrical tape. If you cut through flesh, use bandaids.

The meter has a peak hold feature, so this is an advantage that Joe Schwartz wished for. It does not display watts directly; for that you must multiply amps by volts, either assuming the voltage to be 120/240/etc., or by measuring on the voltage scale. I don't find this to be a disadvantage because for comparisons, knowing the amps has been adequate for me. Another potential advantage of the clamp-on meters is they usually have 1,000 amp maximum scales. On the low (20 amp) scale, there is plenty of precision to compare loads such as 15 and 25 watt lightbulbs.

One interesting thing I learned using this meter is that my computer monitors consume the same amount of energy in normal or screen saver mode.The screen has to be completely black for energy savings. I agree with Mr. Schwartz that knowing energy consumption is the first step towards reducing it.

I have not found in your magazine archives any discussion of AC power controllers (also called power planners) that you connect to an AC inductive motor appliance. These are the ones demonstrated in the larger hardware stores for about US$30. In my experience, they reduce energy consumption of AC motors 6 to 30 percent (depending on load). They offer no improvement with modern, conventional refrigerators, perhaps because the power-shaping circuitry is already built in, or the motor is so closely matched to the compressor load. They are often sold in 6 to 10 amp max load capacity, but I once found a Web site offering larger units that would seem appropriate for larger loads like heat pump compressors or whole-house ventilators. If there is any interest in such an article for Home Power, I might give it a shot, since my ideas for articles on LED flashlights, yagi antennas, and ammeters have already been taken! Keep up the good work. Doug Schaefer • [email protected]

Mr. Schaefer, It has been nearly a year since I came up with the idea of converting my AA Mini-Mag to an LED lamp and three batteries. Since that time, I have discovered numerous additional sources for LED lamps. Of these, the highest output and least cost lamps come from the same source, www.lc-led.com. They offer two white LED lamps that I believe would be very well suited for use in projects such as this. The #500TSW4D (15 degree viewing angle) is rated at a nominal 8,600 mcd output at 3.5 VDC with an operating range of 7,900 to 9,600 mcd, and 3.5-4.0 VDC. The #500TW4D (30 degree viewing angle) is rated at a nominal 3,900 mcd output at 3.8 VDC, with a range of 3,500 to 4,800 mcd at 3.8-4.5 VDC. The cost is very low at about US$22.80 for 15 lamps (15 degree), and US$20.25 for 15 lamps (30 degree). I have 15 of each on order for evaluation and projects. As you pointed out, removing the collar at the base of the LED lamp does allow easier fitting, which is something I had not considered. John Gislason

Focus on Efficiency, Not Generation

In general, too much of the magazine content is geared to energy production rather than energy use reduction. Emphasizing production over efficiency is the same trap that the traditional energy system has fallen into. Please give more information and practical, cost-effective ideas for home energy conservation, since most of us waste energy, and conservation is the most important and least expensive step toward energy independence. Please don't forget those of us in the Northeast, where information on simple, cost-

effective prioritized energy conservation steps for older homes would be especially useful. Bill Houston [email protected]

Thanks, and good comments. Many of our articles hit on efficiency. But you are right, it should be a major mantra. On the other hand, the conception of the magazine was to show folks how to produce the energy they need for their homes, hence the slogan, "The Hands-On Journal of Home-Made Power." Michael Welch [email protected] com

Wiring Batteries

Hello, I put in a solar-electric system several months back, and just added another four batteries. My system is wired for 24 V, and the batteries are 6 V each, so in essence I have three batteries hooked together.

I'm curious as to which way would be best to hook up the new set—should I run the connecting wires to each end of the set (one at the beginning set of four and the other at the far end of the twelve) so that energy circulates more evenly (or so it would seem) through the batteries, or does it make a difference? I hope my question is not too obscure. Thanks, Mick O'Hara

Hello Mick, Couple of things:

1. Don't mix and match the new and old batteries in the same series string. This will tend to overcharge the older batteries and undercharge the newer ones. Wire the four new batteries in a new series string.

2. You can simply parallel the new series string to the series string next to it.

3. The major positive and negative wires used for both charging and discharging should be located on opposing corners at each end of the battery bank. So you'll have one major positive terminal and one major negative terminal located on opposite corners (they will be on different series strings).This configuration will help to balance out both charge and discharge rates throughout the battery bank.

Let me know if you have any additional questions. Joe Schwartz • [email protected]

Love Magazine, except Politics

I would love for the magazine to move to monthly. I await each issue anxiously, and it is a long wait between issues. However, I would rather have you stay at bimonthly than move to monthly and fail at it and then cease publishing (which happened with a totally unrelated mag I used to subscribe to).

I love just about everything about the mag, though I could do without the politics in most cases. I disagree with most of the political views that do get expressed in the mag, and think they are misguided and polarize a community that should focus on what they have in common—a belief in the value of renewables (for whatever reason) and a desire to make them more widespread.

The discussion from all the installers/experts on payback was interesting and I think more info along those lines would be good. I think the RE community often focuses on RE as a quasi religion (we must do this for mother earth/gaia, which I think is a crock), and if RE stays as a religion, it will never grow the way it should. The community needs to find a way to make a solid economic case to the public that they should do this now. I believe experience shows that the "we must do this to save the planet and our grandchildren's future" won't hack it. Most people live in the here and now; they can't be bothered to save for their own future retirement, let alone to make sacrifices now for some nebulous benefit for future generations.

If the technology can't support a solid do-it-now case to the public, then that is where the focus should be—what technology advancements do we need to improve efficiency and decrease manufacturing costs to make RE a no-brainer investment now for everyone (and oh by the way, it will help the environment and our national energy security).

The other piece that seems to need more work is maintenance. I love to tinker, and I'm happy with a system that requires frequent care and feeding, but that won't work for the public. We must have systems that can be installed and just work with minimal maintenance (like refrigerators, furnaces, air conditioners, etc. I have bought used equipment from a local installer who says a good portion of his business is removing equipment from houses that are sold, when the new owners would rather have the system removed than do the required maintenance (due to tech phobia, laziness, lack of time, etc.)

A good area for future articles might be on ways to automate systems—sensors and controllers to track performance, alarm systems that could dial a maintenance company with a trouble report so they could come and fix the problem before there was significant damage. This could even be a big RE business growth area, just like there are many alarm monitoring/maintenance companies. Overall, I love the mag—keep up the good work. Gary Hendel [email protected]

Thanks for the feedback, Gary. It is appreciated. Most of the folks on HP's staff think differently than you about a couple of these things. For example, most of us believe that politics and RE are so closely linked that ignoring politics will handicap an RE future. Another place where we may need to "agree to disagree" are the reasons for using RE. There are lots of different reasons. Right now, early adopters are priming the marketplace. One reason for early adopting is because folks like to tinker (your reason, from what I read in your letter). Another is that it is better for the world environment (my reason).

But, I really like what you say about automation. We definitely need to make RE as easy and simple (and also cheap) as possible—for the masses. As far as going monthly with HP, that would be cool, but you'd have a bunch of burned-out HP folks on your hands. Michael Welch michael. [email protected] com tndepondünt Energy Systems

tndepondünt Energy Systems

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