Learn about new solar industry items with these reviews of integrated photovoltaic products.
Back when the photovoltaic industry was getting on its feet, starting about ten years ago, it was pretty much up to the user to match PV panels to power needs. You bought panels from a manufacturer or distributor and gamely tried to hook them to appliances—all too often a hit-and-miss proposition.
A recent trend in the rapidly maturing industry, however, is toward packages that incorporate cells matched to uses: integrated products. These carefully designed match-ups are an ideal way for those with little experience or expertise in alternative energy systems to get started on the road to electrical independence. And some of them are so inexpensive that you might consider them for gifts this holiday season. What better way to indoctrinate a relative who's obstinately stuck in the petroleum age?
Everyone is familiar with the most common of integrated PV devices, the solar calculator, but there are probably far more of these sorts of products than you imagined. Consequently, we decided to share these reviews of integrated photovoltaic products, a few of the representative items available today.
Energy Sciences now offers two styles of PV-powered, fan-equipped hats. The Solair-cool Safari Helmet, at $69.95, has a small panel on top of the helmet, as well as a battery holder for cloudy climates and a sponge for evaporative cooling. The new Solar Cool Baseball Cap uses the same fan and PV panel as the helmet but locates the cells on the bill. The baseball cap is priced at $29.95 and comes with a sponge but not a back-up battery holder.
If you've ever left your car unattended for an extended period, you know that the battery will eventually go dead if it's not used. Solar Electric Engineering's Maintainer 12-volt trickle chargers sit on the dash of your car and provide enough current to keep the battery alive despite your lack of attention. The panels can be connected directly to the battery or plugged into a cigarette lighter. Two models with different capacities are available.
One disquieting aspect of using an active solar collection system to heat your household's water is that it normally takes utility electricity to do the pumping. Kyocera, a major Japanese manufacturer of photovoltaic cells and panels, has addressed that problem with its Photovoltaic Pump System. Powered by a Kyocera 10-watt polycrystalline panel, the system also includes a DC pump, a freeze-control valve, a flow indicator, a switchable control box, and necessary plumbing. The wholesale/contractor price is $372, FOB San Diego.
Energy Sciences' 120 Solar Experiments is just the gift for a youngster who aspires to learn about photovoltaics. The kit, priced at $31.95, contains parts and instructions to help build everything from radios to burglar alarms that run on photovoltaic power.
Sun Frost refrigerators, designed by Dr. Larry Schlussler, are generally recognized to be the most efficient available anywhere, running on any form of power. And though they're not sold with PV panels directly, Sun Frost refrigerators are designed specifically to operate on photovoltaic power. Available in sizes ranging from 4 to 16 cubic feet—retailing for between $1,250 and $2,500, plus crating—Sun Frost refrigerators may be the answer to the problem of providing food storage capability with low-power photovoltaic electrical systems.
When taken to its roots, wind power is a form of solar energy, since the sun causes the differential heating of the atmosphere that causes air to move. However, we don't usually think of wind power being so directly solar as it is in the case of Energy Sciences' Solar Kinetic Wind Generator. At $34.95, it's food for thought: windmill or fan?
Elsewhere in this issue (see page 50), we show you how to build a nickel-cadmium battery charger that runs on 12 volts. Frankly, we wanted to make it photovoltaic-powered, but the cheapest we could manage was about twice the price of Solar Electric Engineering's solar-powered battery charger. True, SEE's charger won't handle 9-volt cells, but it's still quite a deal. Why, at $19.95, it's not much more expensive than a conventional ni-cad charger.
If a photovoltaic charger for ni-cad batteries is just too cumbersome, MJR Company has the answer. It's D-cell-sized ni-cad has the PV panel built in! All you do is set the dead battery in full sunlight; 28 hours later-about twice the recommended wall-outlet charging period-it will be restored to its full 1.2 volt, 1.2 amp-hour capacity. Perfect for backpacking and other remote uses, they retail for $20 each.
Electric fence chargers are a natural use for photovoltaic power, since they operate on low-voltage DC power and are often located quite a distance from available electricity. Energy Sciences markets both 6- and 12-volt PV versions of the Parmak fence charger. Both versions are battery-equipped-to get through cloudy periods-and carry two-year warranties. Priced at $169.95 and $299.00, respectively.
SunAmp Systems specializes in putting together integrated applications of solar power. Some of its standard setups include Electric Boat Kits for trolling motors, including panels, mounting brackets, regulator, batteries, and wiring (from $559 to $1009 with Mobil or Kyocera panels); SunLight Solar Yardlight, which hangs on a pole and switches on automatically ($495); and a Swimming Pool Kit, which replaces a 1.5 HP AC motor/pump system ($9450). Also available are custom DC evaporative cooling systems and solar-powered water pumps.
FOR SUN FANS
Fan operation provides a perfect application for photovoltaics, since the timing and power of the circulator will be proportional to the solar intensity—and therefore heat. Solar Electric Engineering has three such systems, shown above, ranging in price from $100 to $500. The modular unit is especially intended for RVs and fits in the standardsize hatch cover. The two different-sized fans are intended for gable applications, ventilating attics, greenhouses, etc.
Solar Electric Engineering has a tantalizing prospect: Look for its PV-powered satellite television dish ($1,500 with panel), which is expected to hit the market soon.