Slaying a Watt-Guzzler- Washing Machines Jim Forgette copyright 1991 James F. Forgette Conventional ac powered washing machines, plugged into a large inverter, seem to be the way many home power folks are doing the wash. But is this method the most efficient, or is it just another case of "watt-guzzling"? Another way to power these washing machines exists that consumes FAR LESS electricity - two, three, even four times less. These full-size washing machines are one of the big consumers of home power electricity. Three washes for the price of one saves a lot of electricity- watts that needn't be "thrown out with the wash water". Striving for Energy-Efficiency Pays Off I consider myself an old techie, but the deeper meaning and global importance of the efficient use of energy resources recently came over me in a new way (Thanks HP mag!). I began to look at my entire home power electrical system in a new, inquisitive way. For example, I calculated that I had unknowingly been shoveling about four times more electricity into my old lead-acid batteries than I took out. I realized that my two, 60 watt PVs were not even keeping up with the batteries' self-discharge, let alone providing my home any solar electricity. What an incredible waste! Part of the "lead-acid experience", as its been called. So instead of buying more PVs the next time finances allowed, I first got different batteries that weren't "bottomless pits". I bought some good, used Nicads, advertised as, and indeed, very energy efficient... The improvement is profound. A smaller example, is the "always-on" light in our dining/den/study room. I replaced the tungsten light with one PL fluorescent, same brightness yet three times less power consumption. These and other efficiency changes reduced the amount of electricity we needed to produce, and we had more electricity to actually use. That's what gaining energy efficiency is all about. What About Washing Machine/Large Inverter Method? Many home power folks aspire to, but stop short of, home powered clothes washing. You require sufficient generating capacity, whether it be PV, hydro, wind, fossil fuel, etc... You must buy the extra battery capacity needed. You must shell out $1,000+ for a large inverter. Then, finally, you can run your standard ac powered washing machine on your system. For sure, it's a big step forward in independence and convenience. For my household, we usually washed four or more loads per week. The washer/large inverter combo was the BIGGEST single consumer of our home made electricity. From my view as home "powerplant manager", the washer was THE WASHER, the most stressful load on my inverter and batteries. I figured, if that's what it takes, then that's what it takes, so I grudgingly fed the beast. It did seem a shame though, to be spending so much electricity on just "doing laundry". The Investigation My energy efficiency thoughts kept coming back to the washing machine. Maybe there was to make it consume less electricity. But first, I needed to know more about what I was dealing with. From actual measurement, I determined that my full-size automatic washer consumed about 1,000 watts of power for every thirty minute wash, which is a good estimate for most full-size washers. For comparison, this is like turning on seven, 15 watt fluorescent lights for four hours; or like operating a typical 13" color TV & VCR for five hours. To produce this much electricity (including system inefficiencies), it would take one "sun-day and two 50 watt PV panels. Hey, that's a lot of "amp-olas"! These examples represent just one load washed. So now I had a better understanding of how much electricity the washer used. Nearly all of this power is consumed by the washer's electric motor. Heavy Watt-Guzzling Exposed I wanted to find out how energy-efficient that electric motor was...how much actual work did it give me for those 1,000 watts of power? Through both measurement and calculation, I determined that my washer motor was about 40% efficient. Not very good, to put it tactfully, but typical of mainstream washing machines. From study and experience, I knew that affordable, higher efficiency electric motors existed. Why didn't these appliance-makers use them? Clue: cheapo motors = bigger profits. This was beginning to look like a classic case of "watt-guzzling". I felt increasing determination to install a more efficient electric motor in my washing machine...ASAP! A More Efficient Alternative? Before we could afford a large inverter, I had often dreamed of running the washing machine on DC, simply because we had no inverter. There has been a little booklet (Convert your washer to 12 Volts) in print for years that explains converting certain kinds of ac powered washers to DC. There are even DC conversion kits on the market. Washers converted to DC are promoted as a way to get around a large inverter. I already had a large inverter, bought mainly to run a washing machine, and I had put DC washers out of my head. I hadn't really ever thought of the efficiency of DC motors as a prime consideration. Good quality "permanent magnet" type DC motors are very energy- efficient for their price. The "ac-Only" Crowd In talking with other off-grid folks, some frowned at the mention of DC, stating that their home was wired for 120 vac only. This is no problem because these efficient DC motors also come in higher voltage versions and, with a rectifier and capacitor circuit ,can be powered by standard ac electricity, either gird or inverter produced. Just plug the washer in. The rectifier would add a little efficiency-loss, but the washing machine would still only use half (or less) the electricity as before. Shows you how grossly inefficient the stock ac electric motor really is! The DC and ac/DC Gang Many of us off-griders have wired our homes for DC only or a combination ac/DC system. We could run a washing machine on straight DC, be it 12, 24 or higher voltages. No large inverter is required. My early experiments show that the washer would only consume 1/3 the electricity. These straight DC versions do have a few quirks to deal with. First, the wire size between the washer and batteries must usually be bigger than regular, Romex- type house wire. How much bigger depends on the distance between the appliance and batteries. For 12VDC, use 40 Amps peak, for 24V use 20 Amps and use a Wire-Loss Chart to find the correct wire size. Secondly, a small inverter is required for automatic washers in order to run the washer's ac timer and other internal controls. A good quality, small 100 watt inverter costs about $150. Far less than a large one and it's handy to operate other small ac appliances/tools when not running the washer. If you're a DC purist, then please consider the inverter as part of the washer's internal components. In Other Words This DC motor conversion could be adapted to either low voltage DC or 115 vac home power systems. The only restriction is that some washing machine designs are NOT easy to convert. An automatic washer's slower, gentle wash cycle will no longer function unless additional circuitry is included in the conversion. The Test CAUTION: you should either be a techie or have good instructions if you want to experiment with your washer's innards. I now had the right size energy-efficient DC electric motor, the inverter (but remember that a small inverter is enough), and was willing to install a larger 12 volt house wire circuit to the washer (not necessary for 115 vac). I was game to try the DC motor in my washing machine and see if I could "Slay the Watt- Guzzler". Not wanting to disable our home's washer to experiment, I used an extra spare- parts washer of the same kind to run this first test. Hooking everything up temporarily, I threw in a load of shop rags and let 'er fly. The washer bean washing, but way too fast. Funny to watch but not good for clothes or washer. A few fan-belt and pulley changes later, I finally got down to measuring power consumption. The Results To my delight, the DC motor/small inverter team was consuming only about 300 watts (25 Amps at 12VDC)! Remember, the same kind of washer with ac motor/large inverter combo consumed 1,000 watts. I couldn't believe it at first. It was too good to be true, but it was true. It meant that if I used this DC motor in our washer instead of the stock ac motor, we could wash three loads of clothes for the same amount of power that one load used to consume. "Looking Good!" My converted washer started life as a Ward's Signature model. It holds twenty pounds of funky laundry. I used an 1800 rpm, 1/2 hp Scott 24 VDC motor. Since this Wards design reverses the direction of the motor, I used two heavy duty solenoids to switch the polarity of the motor. The solenoids I used are made by Stancor and are SPDT 50 Ampere models (types 70 and 1240). The round trip wire distance between the washer and my 12 Volt battery is 120 feet. I used recycled 0000 gauge aluminium cable to connect the battery to the washer. I also changed both the drive and driven pulleys which increased the efficiency even more. The use of a 1200 rpm motor and a larger drive pulley can boost efficiency. I discovered that proper belt tension and the use of a toothed (cog) belt can also increase efficiency. Why Am I So Jazzed? Why do I get so stoked about something as mundane as an energy-efficient washing machine? I'd rather see my hard-won electricity going toward something a bit more evolved than doing laundry. Without needing a large inverter, additional gasoline generator time, more PVs, or larger battery storage, I can now use the extra power for other appliances or simply to gain more days of battery storage. On a larger, national scale, much has been written about the serious need for more energy-efficient appliances. Lighting and refrigeration are getting most of the spotlight. The common washing machine is also a widely used major appliance. When I think of my now discarded ac motor and imagine it multiplied by all of the ac washers in the world, I realize that many large powerplants are unnecessarily feeding these watt-hogs. The same tale of guzzling is true for virtually all mainstream ac motor driven appliances. It's a crime...Hey Congress, here's a chance to EARN some of that $100,000+ salary. Let's see a REAL Energy Policy, one with cornerstone-emphasis on sustainability and the well- being of future generations. "Duh", as comedian Jay Leno would say. MAKING THE CHANGE "FOR KEEPS" I first installed a new circuit between the batteries and washer, including a fuse or circuit breaker. ALWAYS, Always, always, include these safety features in you home wiring. No matter how destitute or in a hurry you may be. You don't want a house fire or worse. I was ready and couldn't wait to get my hands on that watt-sucking ac motor. It took some experimentation and time to decide on, gather, and mount everything "for keeps". As I had other duties, a week went by before I was finished while dirty laundry kept piling up (so what's new?). When the conversion was complete, the washer got a real workout chewing on that mound of laundry. The washer ran "just like downtown". I felt proud and thrilled every time I looked at the meters and calculated. Sure enough, only 1/3 the consumption as before. Alright!! Just to gloat for awhile, I set the old ac motor outside my shop door so I could growl at it as I passed by. Conversion Difficulty vs. Brand of Washing Machine The easiest type of washers to convert are the Whirlpool models made before 1985. These same models were also sold by Sears under the Kenmore brand. This type uses an easy to replace motor that runs in a single direction. The motor is coupled to the washer's mechanism by pulleys and a belt. There are thousand of these washers available used & working, or in various states of disrepair. All wringer washers are old enough to use belts and pulleys and they are easy to convert to an efficient motor. Somewhat more complicated to convert are the Wards Signature (LNC) models, like the one I converted. Since the motor reverses its direction, one must use heavy solenoids to switch the motor's polarity. Most Maytag models also fall into this category. In new washers, the 20 pound Magic Chef and Admiral fall into this category Some washers are very difficult to convert because the motor is directly coupled to the washer's drive assembly. Some types even use shafts on both ends of the motor, one for the washer and the other for a water pump. These types are very poor candidates for a motor transplant. Included in this class are some of the newer Whirlpool, Kitchen Aid, GE, Frigidaire, Westinghouse, and Kenmore models. A look into the washer's innards will give you some very good information about its capacity for conversion. Is the motor's shaft directly coupled, or does it use a pulley/belt setup? Pulley/belt types are easier to convert. Is there lots of space surrounding the motor, or is it packed in like a sardine sandwich. Chances are the DC motor will be of different dimensions that the ac watt-hog it replaces, so extra space makes the conversion easier Can You Do It? That depends on your "tinkering" experience, the brand and model of washer you want to use, and how much money & time you are willing to spend. I recommend the qualifications-guidelines listed below. If you stick to an easy-to-convert washer, it's not all that difficult. The number of parts required aren't many and the actual installation shouldn't take longer than an afternoon. There are basically four approaches to take if you want to enjoy the energy-savings of a converted washing machine. 1) Convert from scratch with no Instructions For non-techies, forget this approach. For techies, have fun! You are exploring new territory and will experience the hazards faced by all pioneers. Keep at it, and do it right. Document your work and let the rest of us know the path you followed. After all, that's what pioneering is all about. 2) Convert from scratch, guided by instructions Published, "do-it-yourself" instructions can be either brief or comprehensive. The briefer they are, the more experienced/skilled you must be in mechanics/electronics to read between the lines. The only one I have experience with is the little instruction booklet, "Convert your washer to 12 Volts by David Copperfield. It is a bit dated, contains some errors, and is quite brief for most models. It does adequately cover the most popular second-hand washers (and Maytag wringers) IF you are experienced with "creative" repair of things. You must be willing to spend time locating and gathering the correct conversion parts. 3) Convert with a "Do-It-Yourself" kit I'd recommend you have at least minimal mechanical and electrical skills. Or get a kit and have someone you know who is qualified install it for you. Which kit? Like everything else, there are kits and there are kits. Quality, completeness of parts, instructions, and price are the key concerns. I'd ask first for a product fact-sheet to compare these variables and to find out beforehand what the job requires for your situation. One company's kit may not include "optional" parts (that you'll need) and yet cost more than a competitor's kit that does include the same parts. Compare quality and completeness of each kit. For a DC system, does robust , flexible lead-in wire and connectors come with it? How about a enclosed electrical connection box (enclosure)? Does the new motor have just two poles/brushes (so-so) or four poles (longer maintenance-free life)? For large/extra large capacity washers, is the kit's motor only a 1/4 horse, when a 1/3 or 1/2 horse would run cooler and last longer. For automatic washers to be run on DC, does a small inverter come with the kit? What kind of inverter is it, a square wave type with no voltage regulation? Crude ac won't protect the washers electronics. Does it come with both high and low battery cutoff features? This feature protects both washer and batteries, the Statpower PC100, for example, is sturdy, reasonably priced and has all of these important features. Compare and finally make sure the kit is for your brand and model of washer. 4) Buy an Already-Converted, Brand New, Full-Size Washing Machine I haven't seen one on the market...yet. How Much Does It Cost? These home powered examples do not include any costs for heating wash water...See the sidebar attached to this article. If you buy new quality conversion parts, separately at retail price, you could spend over $500 (including wiring, fused panel box, and a small inverter). A conversion cost even this high would be worth it in the long run, especially for "heavy users". Consider these examples using full-size, standard ac washing machines and methods. At the laundromat, wash five loads of clothes per week at $1 per load, and you'll spend more than $500 in two years. That doesn't count getting there and back or the eco-costs of most on-grid power generation. In the end, none of this expense went toward upgrading your home power system. With PVs and batteries, five loads of clothes per week requires roughly two, 50 watt PV panels ($700) dedicated just to the washer, a large inverter ($1,000) dominated by the washer whenever you do laundry and 1,400 extra watt-hours of battery capacity (3 cloudy days of storage). In stark contrast to the last example, a converted washer, also at five loads/week will cost the price of the conversion (between $250 and $550), only one, smaller 35 watt PV panel ($250) dedicated just to the washer and 480 extra watt-hours of battery capacity (3 cloudy days of storage). If you already own a large inverter, it is now freed to run other high- powered loads or to just rest. The efficient 115 Vac versions require a medium-to-large size inverter and consumption will be about 18% higher than the "straight" DC versions Access Author: Jim Forgette, POB 207, San Andreas, CA 95249. Parts: Alternative Energy Engineering (AEE) Catalog, 800-777-6609. Motors: Suntools, 707-964-9019 or AEE, 800-777-6609. Instructions: You can get "Convert your washer to 12 Volts" by David Copperfield from either the Real Goods Catalog, 800-762-7325 or AEE Catalog, 800-777-6609 (both also have wire, connectors, and inverters). Kits, motors, parts, advice, and new efficient washers (in late 1991): Wattevr Workstm, POB 207, San Andreas, CA 95249. SIDEBAR Be Wary of "Official Efficiency Ratings" The energy-efficiency rating of new washing machines is stickered to the washer itself and printed in publications like "Consumer Reports". For home power systems, these official ratings are completely inappropriate. The problem is that the cost of heating wash water is included in these ratings. For an "on-grid" home (water heated by natural gas or electricity), the cost of heating wash water is overwhelmingly the main utility expense. For "off-gridders", producing the electricity to run the washer is the primary concern. In fact, the on-grid cost of heating wash water so dwarfs the cost of electricity to actually run the washer, that "Consumer Repots" doesn't even include the washer motor's electrical consumption in their rating calculations! Quoting "Consumer Reports"; "...we consider hot water use ALONE (my emphasis) the most meaningful gauge of a washer's energy efficiency." Well, for typical on-grid washers this is true. But in effect, what's actually being rated here is the power consumption of the home's hot water heater, not the washer itself. To someone on home power with a solar hot water system (homegrown and/or already paid for), these official ratings are absurd. "What do they mean, hot water costs? Why don't they include the cost of pumping water too, or the cost of laundry soap and bring it home from the store!" So in shopping for a new washer (or any appliance that uses hot water), home power folks comparing official efficiency ratings should be aware of what those ratings are actually measuring. Perhaps these ratings should also provide data for just the electrical consumption of the appliance itself. Maybe we off-grid'ers need our own non-profit rating agency- "Conserver Reports"? Jim Forgette.