Agates in the Sahara

Doing trips through the desert means to look for a safe place over night and you will have a look what is surrounding you - especially on the ground like snakes, scorpions and so on. At the fifth trip in Algeria on the way to Mali friends of mine and me rested in the south of Algeria along the Tanesrouft piste. Next morning we found a field with a lot of stones - and some of them were agates.
Quotation Wikipedia :
Most agates occur as nodules in volcanic rocks or ancient lavas where they represent cavities originally produced by the disengagement of volatiles in the molten mass which were then filled, wholly or partially, by siliceous matter deposited in regular layers upon the walls. Such agates, when cut transversely, exhibit a succession of parallel lines, often of extreme tenuity, giving a banded appearance to the section. Such stones are known as banded agate, riband agate and striped agate.

http://en.wikipedia.org/wiki/Agate

Since last year I started to work on the agates in form of tumbling them in a cylinder filled with fine Siliciumcarbid (SiC) which is a syntetic abrasive and water. Then you will have to wait for several weeks and then you can see a result - as shown in the following photos.

Resume photovoltaic plant

My photovoltaic plant exists now 2 1/2 years. In meentime I lost one modul by shot or crash from a meteoric stone ( I think) But nevertheless the plant is running fine and gives me good results in earning money. Over the whole time I earned 6,435 EUR for selling electrical energy to the net.

In Germany more and more ppl decided to do such a kind of investment, cause the returns of shares is much more worth - in the moment.

the heart of the photovoltaic plant

To bring the DC power of the modules to the AC net - you need an AC converter. The AC converter normaly is build up structuered up to three strings of modules, so you can organise different modules in power or attacked modules by shadows - to different strings. Each string is managed by an electronic device called MPP Tracker. This device is always looking for best results in power. To care for over- heating at the converter that reduces the power automatically I decided to construct a suspension in the free room to have a maximum of cooling air all around.

photovoltaic plant - conclusion

the project now is ready for work. It exists of 28 modules that produce 5,600 Watt peak. In real I expext 5,600W x 0,85 = 4,760 Watt peak cause we are not in Italy or Spain, where the sun works much more harder. The mounting of the modules was easy cause I used a professional roofer with his crane. The complete surface of the modules is 47 square metres. Because of shadows existing in winter and in the evening hours, the roof is not totally used.

photovoltaic plant - the preparation - reasons to do

Coming to the decision to buy the modules and to build up the plant means to have a check-list. Answering this check-list will show you, if it makes sense to invest. Here a short form - but you better move into a forum of photovoltaic. For german speaking people :

http://photovoltaikforum.com/pv_faq.php

In Germany such a plant is promoted by the goverment - so you´ll get from your energy company 51,80 Cent / kWh up to 30 kW plants. The promotion will be reduced every year....so the 51,80 cent are only payed, if you start the project in 2006. Price guarantee for 20 years.

Check if you have a roof to the south; the slope should be between 32° and 38° - that´s the best situation.
In the next posts I will give some more pics about my experience.

the sun is always and everywhere

visiting the desert several times - you will not forget how mighty sun emits energy. After a long ride every day we took a shower in the evening with solar heated water coming from the water tanks on the roof of the landrover.

So finally I decided to spend money in some solar projects on the roof of my old house. In 1999 I bought a thermal solar collector equipment to heat up the water we need. So we saved in the middle 500 EUR in a year on gas.

In this days I will start with a project of photovoltaic elements. The power in peak will be 5800 Watt and we will earn around 51 cents for one KWh.
The elements are from SOLARWORLD and will be placed on the roof of the old barn. See the construction on the attached photos. The deepest line will be in the shadow with 30 % of the surface in December and January - hope I will not loose to much of the sun power. If you have experiences with similar projects, please write a comment.

Biker in Algerie 1991 (2)

Even travelling in winter Algerie is very warm and sun is strong. We did like the evening most. Seeing the colours changing when sun goes down - each day from a different rest place over night.

Some photos from Harald our Toyo pilot - always ready for a joke.