Emergency Backup Power: And don't even consider batteries for that 0.1% of the time when the grid goes out and you need backup power. For power backup in the rare blackout a few hours every year or the bad day or so every decade or so, simply use your car generator and an inverter. See some of this on my Prius Power web page.

NET METERING: Of course, all the benefits of grid-tie solar depends on having NET METERING in your area. Meaning that all energy you put into the grid you can get back out at the same cost as putting it in. This is the case in most energy conscious states bylaw. It is a win-win for both the homeowner AND the utility company, so there is no chance it will ever go away.

Off-grid battery systems are ideal for small remote electric transmitters and radio systems on mountain tops where the load is constant (and it is the only possible solution). But it makes no economic sense whatsoever in a place where there is access to the grid.

Keep your grid! (if you have it). Yes, you will have a $10/month metering fee even if you use zero net power, but that is a trivial cost to pay to avoid messing with batteries for the rest of your life and replaceing them every 3 years, and losing 30% of all power you generate, and wasting half of your excess solar power in the summer.

Hope this helps

Bob, WB4APR

Please see more on my Alternative Energy web page!
and / or, take a look at my Solar Power PPT presentation

The rest of this page has not yet been edited out and is just som old stuff on other pages.

solar augmented Salvage Prius, And there is another page on using the Prius for emergency field power, See my nearly born-again (powerpoint) conversion to a Solar Junkie in August 2009!

POLLUTING ALTERNATIVES: If you look carefully in the photo of my array at the top of this page, you will see the smokestacks of the 500 MegaWatt A.H. Wagner coal-fired generator plant just 4 miles down the creek. By my calculations, just my home alone consumes about 10 MegaWattHours (MWH) of electricity per year. I hope to generate my own solar 10 MWH to eliminate completely my share of the pollution from that plant which amounts to:

22,000 lbs of Carbon Dioxide
350 lbs of sulfur dioxide
1 ounce of Uranium and Thorium
.00004 ounce of Mercury

All of this pollution that I am responsible for is falling on the nearby Chesapeake Bay and watershed and my creek. Yet, I want to eliminate my contribution to this pollution by installing my 8 kW clean-solar system which will just about break even by producing my own annual 10 MWH's of clean-renewable-energy. So, at my own expense, I am offering to clean up the Bay by having solar panels on my pier, but am blocked by an outdated and short-sighted law of the Maryland Department of the Environment who are charged with protecting not just the water under my pier, but the air above and the soil beneath.

Plan-B Solar-in-Yard: 21 Dec 2010 - So, after 9 months and $2000 of fees, the MDE's denial of panels on piers still stands. So I designed the panels to sit on the only sunny part of my lawn down by the water.... Don't be fooled by the winter image above. My roof is more than 50% shaded throughout all times of the day and most months of the year. So we submitted for a building permit in September 2010 only to be immediately DISAPPROVED! Maryland does not allow anything to be built within 100' of the shoreline. So, with additional fees, I applied for a Variance. On 21 December 2010 I appeared before the Hearing Officer and presented my case. Here are some of the materials I used:

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Environmental Benefits of Solar: The above two images show the pollution-elimmination impact of my solar project. Each 3'x5' panel eliminates about the same amount of pollutants in a year as about 8 mature trees remove in a year. This means my 42 panel array is equivalent to the environmental benefits of about 300 trees compared to coal. But even more telling is to look at not just the pollution impact of coal electricity, but also the sheer magnitude of environmental distruction.

Unseen Impact of Coal Electricity: In the image to the far right are 4 tons of coal which is about the energy equivalent of the 10 MHhrs of energy our house requires per year. Not only do we energy-consuming-&-wasteful Americans not see this tonnage, we also do not see the 80 tons of trees, topsoil, habitat and dirt that has to be pushed off a mountain top in West Virginia and into the nearby valleys and streams just to get to that coal. This 80 tons of decimation of the environment PER YEAR for my one house is shown in the near image to the right which shows four 20 ton freight cars needed to move that debris. The next image below right is just one of the hundreds of mountains and habitat in West Virginia being destroyed for our coal energy addiction... Folks, this approach to our environment IS NOT SUSTAINABLE!

Variance Issues: With the proponderance of benefits of my solar project in my front yard, the County did agree that the varance was appropriate, but with one big catch-22 provision. They requested that there be the standard mitigation for any variance in the 100' foot critical area buffer. This means that the disturbance in the buffer area (690 square feet) must be offset with 3-to-1 or 2000 square feet of new trees. In otherwords, I can have the solar panels, but I have to plant so many trees in compensation that my lawn becomes a forest and we are back to square-ONE, that is, no solar access!

The Hearing Judge has 30 days to make a ruling. He did! In our favor! Now the building permit has been submitted and then we will probably have to do battle with their requiements for disturbance mitigation. We will see if sanity prevails.

SOLAR PRIUS:

My first alternative energy project was my Solar Plug-in Hybrid Electric Vehicle (PHEV) I built from a salvage Prius.. It had been totaled on the drivers side, but I just beat it out with a sledge hammer and coverd the bashed-in door with the white sign! This soon morphed into my Prius Field-Day Power project to combine high power solar, with thousands of watts of backup gasoline driven generator power in the Prius for providing emergency power for field operating events such as the annual Amateur Radio Field Day or Scouting events shown below.

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PRIUS POWER: The Prius is a power station on wheels. It has a 12 volt electrical system for normal car accessories, and a 220 Volt 7 Amp-Hour Battery for propulsion assistance, two 50 kW motor-generators, a 50 Kw DC/DC converter/inverter, and a 76 Hp gas engine all integrated into a seamless power system. See more on my Solar Plug-in Prius

115 VAC Power: is provided by a 1200 Watt AC inverter running on the car's 12 volt power system (shown in the right photo above). This 1200 watts drawn from teh car's 12 volt system is augmented by the 100 Amp DC/DC converter from the car's propulsion batteries and generators.

SOLAR-POWER: . Adding solar panels to the Prius not only provides free energy to offset the cost of gas a few percent, but also to provide an effective application for solar power in other places where you might need it. The solar panels shown here can provide as much as 215 peak Watts of power good for about 1.7 KWh of free electricity when parked for 8 hours in Arizona sun. (unfortunately, only 800 Wh in Maryland Sun). Solar Power portability gives peace-of-mind where there is no gas or plug-in electricity available. . (more on my Solar Prius)...

When you can take solar power where you need it, then its value can be far greater than 15 cents per KWH and is cheap at any price. . Just consuming it in the Prius is an equivalent payback of 30 cents per KWH compared to the 15 cents at home. . Plus it reduces dependency on foreign oil! . A 1200 Watt AC inverter in the back (see photo above) provides plenty of AC power to go.

Emergency Solar Power Trailer: I had a few extra low voltage solar panels so I put them on the solar trailer to the right. It contains about 300 watts of solar panels plus a deep cycle marine battery and 1200 Watt inverter. The top wood section of the trailer folds over to not only protect the solar panels during travel but to also hide them out of sight when parked or not in use. When closed, the top wood section looks like an open top trailer with about 6 inch sides. The false bottom conceals the nested solar panels.

In addition, when open, the bottom set of panels are also hinged to give access to the battery and inverter below. Plus this area provides hidden storage for extra power cords, cables and accessories. (see picture)

220 VDC POWER CONNECTORS: . One of the first issues with distributing 220 VDC power is finding a safe connector that is innexpensive and readily available yet, cannot be confused with any other electrical connector. . This connector must be unique to prevent anyone from plugging in any non 220 VDC device. . The connector we came up with was a standard two-prong power plug but with two PREVENTION devices to prevent inadvertant plugging in of other devices. The connector is shown above right.

A standard two-prong socket is used, but without the usual 3rd ground pin. . This blocks the use of any 3 wire 115 VAC power cord. . In addition, a 3/16ths inch nylon protrusion is fixed to the center of this receptical inbetween the two prongs. . This blocks the use of any 2-wire 115 VAC devices. . To make a mating two prong plug, a standard replacement plug is used but the center is drilled out to pass this blocking pin as shown in the photo. . On the right, this center pin protrudes into an unused, and isolated area of the hard plastic plug construction. . These connectors cost under $2 each for both the plug and the receptical.

Lightweight Power Cords: . Because of the much lower current demand at 220 VDC, a #18 zip cord can easily carry plenty of power over hundreds of feet. . In the photo to the right, the original 25 feet of large orange extension cord were removed and about 120 feet of #18 lamp cord will fit on this convenient spool system. . The current carrying capacity of #18 is as high as 10 amps, but I limit mine by fuses to only 5 Amps. . Again, the outlets are blocked from any inadvertant use by the uninformed by the dual protection-blocking system. . Only switching power supplies or other loads that can operate on 220 VDC are provided with these matching plugs.

(YOUR MILEAGE MAY VARY!)...

Bottom line: . The time is now to go solar! We cannot continue to send billions of dollars a day overseas to buy polluting oil for our energy needs when it is right there outside our door. Also think in terms of your total energy footprint and consider how to integrate your transpotrtation demands into your own home solar system and energy needs.

Bob Bruninga, WB4APR,
President APRS Engineering LLC