PV Gap

Bessie Said:

Are there SOLAR powered traffic lights in Africa?

We Answered:

Pretty sure there would be, especially in the more developed areas (e.g. South Africa) although now I think about it I can''t remember seeing any. Most of my time in Africa has been away from the developed countries...

There are definitely solar powered street lights - and big ones on major highways at that; I used to have to regularly drive to and from Yenagoa (capital of Bayelsa State in the oil-rich Niger delta region of Nigeria) and all the lights along the highway and main road of the town are solar powered.

Daniel Said:

would like to set up solar power to run 750 watt freezer in the gambia west africa. what do i need to buy.?

We Answered:

Is the freezer 230V ? If it is you will need a voltage converter to up the solar panel voltage, and change it from dc to ac. The other thing to check is the load, ie the current being drawn by the freezer against the current output from the solar panel. 750w is roughly 3 amps. You will need solar panels that will supply more than that because, under load, the voltage will drop, possibly to a level to where the freezer stops working!
Thats not everything, but enough to get you started!

Bonnie Said:

Would the U.N. sponsor a competition between solar power and turbine power? Please explain why or why not.?

We Answered:

yeah its all a conspiracy

Sharon Said:

Laptop battery charging - Power conservation question?

We Answered:

Actually, I thought about your question again. Assuming you never discharge your laptop battery, leaving the whole thing plugged in will be best. Actually discharging and charging the battery is where any efficiency losses would come in the picture. If you don't use the battery much, then the only charging that would take place is to offset internal discharge of the battery (which cannot be prevented). What may be worth checking is to see if the total power usage from running the laptop off the battery then charging is different from just having the laptop plugged in while using it. You can do this testing with a portable meter from the hardware store (probably going to cost about $20). Those meters are designed for AC, however, so if you use an inverter there might be additional losses from that too.

Another thing to consider is that a fully charged battery inside your laptop is additional storage for your power system. If the weather is dark on some particular day, you may want to go ahead and use the internal battery and make up for that on a sunny day.

Good luck!

Stephen Said:

Why is solar power not used more commonly in Africa?

We Answered:

There are projects to supply solar electricity to remote villages in Africa and other places. The idea is that school children have rechargeable fluorescent lamps which they take to school. The school has a middle sized solar cell array which charges the batteries in the lamps during the school day. When they take them home, the lamps give enough light for the children to do homework or the family to read a newspaper or book. This avoids the use of dangerous and smoky home-made kerosene lamps. This project is a Canadian charity.