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Amp-Hour Meter


Four Batteries 280 A-hr @ 12 Volt

Amp-Hour Meter


Four Batteries 280 A-hr @ 12 Volt

Shunt (in)

Shunt (in)

To ac Loads

Above: The Ampair hoisted into "flying" position hangs from the foresail sheet in the triangle between the mast and the forestay.

I use a voltmeter, homebrew Ah meter, and a couple of ammeters to monitor the system. The ammeter for the wind generator has a dual function—10 Amperes means it is not a day for sailing and I think twice about going out! The Ah meter was built from a Home Power Magazine circuit.

The load on the boat is mostly lighting and the water pump. A Powerstar 700 watt inverter is used to run various 240 vac loads including my computer and TV. It also powers my old valve amplifier for the stereo. I know that valves are hopelessly inefficient but I wouldn't change it for the world. I would rather switch off some lights.

Living off the grid and away from normal services, even if they are just up the creek, feels good, as I'm sure every remote boat or cabin dweller knows. I could have chosen to plug into the mains onshore but I am happy with the knowledge that all that ties me to the shore is a couple of knots.


Author: Martin Cotterell, Sunpower, c/o Mill Cottage, Seisdon Road, Trysull, UK, WV5 7JF ^

To ac Loads

Above: The PV modules, and the harbour itself, reflect the setting sun in a placid scene of Gebroeders at its mooring.

ANANDA POWER TECHNOLOGIES four color on film negatives full page This is page 15


Harold Sexson

©1996 Harold Sexson

©1996 Harold Sexson

Above: Harold poses in his newly completed solar room with its beautiful terra cotta floor

If you have a south facing side of your home that will accommodate a solar room, you can have years of enjoyment and energy savings. Ours includes tile floors, ceiling fans, and seating areas. Here's how to build one.

Solar Room Pointers

• A south facing patio or open unshaded area is the start for a solar room addition to any house. The longer the room, the more solar gain in the winter months and the more tolerant it can be of fluctuations in the weather.

• The more rooms of the house that open into the solar room, the more heat can be used in the house without fans or blowers. Cutting a door or two into the home where windows exist may help.

• Flooring should be reasonably dark to absorb most of the sun's warmth.

• The better insulated the room is, the longer the heat will stay.

• Added thermal storage in the room will help during longer periods without sun.

Length of Our Room

This house already had a 36 foot long south facing patio with 3 foot tall railings all around. The first thing I did was remove the railings and extend the patio length another 14 feet to include the last bedroom on the end of the house. This also improved access to two bedrooms and the living room and, after adding a door, to the family room.

Roof Line

Having the roof line match was a challenge since the foam roof (polyurethane, common in the Phoenix area)

should look the same as the existing roof. This was done by having the same company that replaced the roof a year before add the foam to the new section.


The existing eves on the house were one foot wide which was perfect for the ten foot width of the room. In the heart of winter the sun shines on the entire tile floor and my thermal storage (adobe bancos). This makes it enjoyable to walk on the warm floor in the evening when it is cold outside. In the summer the sun does not shine on the floor at all and the floor is cool.

Sliding Doors

The eight double pane sliding glass doors were purchase used. All of them look the same for aesthetics. Since the posts for the original patio were not placed for even spacing, they were moved by a few inches to accommodate the doors. Each door is a standard six foot door, with two placed between each post.


Insulating the ceiling and end walls was next. Before installing the insulation, aluminum foil was pressed up against the existing ceiling and walls to add additional radiant heat barrier. The insulation is Celotex "Blackore," one inch thick with foil on both sides. These were cut to the width between the 2X6 studs and force fitted. Three layers were added making sure there was an air gap between each sheet to add to the thermal reflection. Each sheet has a 7.2 R value, making the 5.5 inch (a 2X6 is really only 5.5 inches) space a respectable R-21.6. This would not be possible with standard fiberglass insulation. Although cheaper, R-14 would be the limit.

End Windows

One window was added in each end. Double paned sliders were used here, as well.


Saultio tile was used because it fit the style of the house and it was a less expensive option. Patterns were made in the flooring to add some "homey" atmosphere and get away from the hall-like appearance of the long room. A tile saw was necessary for the cuts to make the patterns. After laying out all the whole tiles, the tile saw cut all the other tiles in one day.

Above: Harold finishes the installation of foam board insulation on the ceiling Banco

The seats for most of the solar room are made of adobe brick. They were made from the dirt in the back yard. Although brick making is a long process, it provides excellent thermal storage, provides nice seating for the room, and fits the decor of the home. They were covered with expanded metal and plastered with an elastomeric stucco made by Sto that will not crack if movement in future years occurs.

Ceiling Fans

Three ceiling fans were added to increase lighting and the circulation of the air when sitting in the room. By running the fans in opposite directions we get a circular flow in the room.


An insulating paint was used that was made by Insulating Coating Corporation (Aztec #300 interior paint). It acts as a sound deadener and insulates to R-20 in the summer and R-5 in the winter. Although more expensive per gallon, the paint lasts ten years and can be made in any color.


Summer months in the solar room are not as hot as would be expected. A high efficiency evaporative cooler is in one end of the room. Using a thermostat, the cooler not only keeps the solar room cool, but also the rest of the house. On high humidity days the doors to the house are closed and the windows are opened in

Below: Covering the adobe bancos with expanded metal prior to the application of the stucco.

the solar room to let the heat out. The house is also cooled by standard refrigeration during this time.

Transition Months

In the transition months the sliding doors are open to either let the heat out or capture cool evening air. By opening the house doors we can maintain comfortable temperatures without heating or cooling. Occasionally the blower in the cooler is used to blow out the warm air in the house for a few minutes.


The cost savings to heat the house in the winter is dramatic. When Phoenix had 20° mornings in January and 50-55° highs during the day, the total heating bill was only 14 dollars over the normal gas hot water and dryer. The typical temperature of the room in the winter is 80° in the daytime and 68-70° in the morning.

There are other basic assumptions that must be considered when figuring how much savings there are with the room. First is how much the doors are left open or continuously opened and closed. This is a big factor in the winter if traffic is present. We do not leave the doors open in winter except to pass through.

Second is your personal comfort zone. If you are cold or hot with only a couple of degrees fluctuation in temperature, the savings will be minimal. We have a summer maximum in-house temperature of 80° if the humidity is low, and 65° in winter. We wear winter clothes.

Total Cost

I built the entire room myself, except for the foam on the roof and the drywall hanging and finishing. The total cost was about $4,000 and about six to nine months of working evenings and weekends. I figure the pay-back time to be about five to eight years.


Based loosely upon a green house, the solar room is not a new concept. An excellent book on greenhouses is Bill Yanda and Rick Fisher's The Food and Heat Producing Solar Greenhouse.

The room is a useful area for gatherings and children's play area. It added value to the home and gave us energy savings. Adapting a design to your particular home is a challenge that should start with a sketch of the south facing side of your home. Make pencil sketches so they can be changed easily. Even letting things sit for a while can help break through a block in the design. And remember, the sun's heat is free.


Author: Harold L. Sexson, 5445 East Caron Street, Paradise Valley, AZ 85253 • 602-998-9055 • FAX 602998-9067

The Food And Heat Producing Solar Greenhouse by Bill Yanda and Rick Fisher, ISBN 0-912528-20-6

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Solar Panel Basics

Solar Panel Basics

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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