SOLAR ENERGY AT ECOACRE
Solar energy provides the power at EcoAcre. Photovoltaic cells assembled into modules provides the electricity for the home and the water well.
PV modules, batteries and inverters on the solar trailer. This was assembled to provide initial power for the trailer and water well. The same platform has been upgraded over the years to accommodate more batteries in a large metal enclosure. A larger invertor has also been added. The modules have been located on the ground near the trailer.
The modules are on a rock base and are laid in place and each module is plugged into the system. Most of the modules were made in 1980 and still work fine.
In winter simple metal legs tilt the arrays to absorb more energy from the low winter sun. Additonal modules have been added for more energy and to test the effectiveness of different types. The total power from all the modules is about 100 Amps at nominal 12 volts DC. On average 5 kWh are produced every day. More in the summer than in the winter matching the increased use of electricity in the summer for irrigation, refrigeration and cooling.
Twelve 6 volt golf cart batteries store the energy produced by the PV modules for nights and overcast and rainy days. A gas generator is used if the batteries need additional charging.
Enclosures for inverters and other equipment
Inverter is in the top box and metering, controls, and connectors as well as a back up inverter are in the bottom enclosure.
A tracking PV module mount that follows the sun providing many more hours of peak power throughout the day in the summer. The tracker is operated by the temperature differential on the tubes on if the sun is evenly heating the fluid filled tubes on each side of the trackers. Gravity caudes the tracker to pivot towards the cooler side until both tubes are evenly heated. It has no electronics, motors or parts that are costly or need any energy, maintenance or repair.
The solar powered evaporative cooler, was built for a few hundred dollars. It uses the same 12 volt DC fan as used on automotive radiators and a low cost 12 volt marine sump pump. The cooler reduces the temperature by around 20 degrees it also provides a lot of air movement, moisturizes the hot desert air and removes dust and pollutants. The maximum power it uses is 100 Watts DC provided by the tracking PV collector. The energy a conventional Air Conditioner would use for a home this size would be around 3000 Watts AC and it would cost several thousand dollars to install
Solar Water Heating
Thermosiphon Solar Water Heater that provides most all of the hot water we use. It has an 80 gallon tank and works with warmer water in the collectors rising into the storage tank displacing the cooler water which descends down the pipe the right where it is heated and repeats the process. When the collectors are cooler than the water in the tanks the water quits flowing. It needs no pumps or electronic controls or separate storage tank. A tank type propane water with a pilot light used more than 5 gallons of propane a week. A tankless propane water heater with electronic ignition used that much propane in a month. With this solar water heater and a tankless backup water heater 5 gallons of propane can last almost a year. The same type of panels will be used to provide hot water for the radiant floor heating system to reduce propane use.
SOLAR COOKING AND OTHER USES FOR SOLAR ENERGY
Even though the main uses for solar power at Eco Acre are for electricity and hot water. Other special solar applications have been used and some have been very effective. Solar cooking for us is very nice and actually convenient for many foods since solar ovens slow cook food and wont burn so we put in the food adjust it every hour and have hot meals in a few hours. In many poorer countries Fuel for cooking can be expensive or require many hours of collection and gathering and also contributed to deforestation. Solar ovens can also increase health and saftey by eliminating the dangerous smoke from cooking, sterilizing water and allowing women to cook at home rather than going out into the countryside to gather wood.
This is a Sun Oven made in the USA gets up to 350 degrees and can bake bread and other foods. It works real well as a slow cooker and can hold two pots so that stews, beans and rice can be prepared. In the summer we keep the house cooler and save energy by cooking much of our food in this oven. We get food from the garden and cook it in this.
Sharon cooking on a homemade solar cooker that only uses cardboard, foil and a cooking bag to cook foods and boil water.
A homemade experimental parabolic cooker the box cooker seems to work better for most tasks.
A parabolic cooker can achieve high temperatures for frying and grilling foods can cook very quickly. Must be aimed at the sun and can burn food if not watched. Eye protection advised.