Our team for upgrading my home from National Solar and Power from left to right: Alfred Maele, Steven Machilika, me, Elias Lazaro, and Ben Salala.
On Sunday, my friends from National Solar and I completed the next phase of work on my electrical system. You can see a compete set of (my first) digital photos at my new site on Flickr.
I had the following goals:
1. Upgrade the power generation in the windmill
2. Upgrade the battery technology and capacity, to provide more even power for more hours at a time
3. Increase the brightness of the lighting (lumens) to make it easier for my family to accomplish tasks at night, especially to read.
4. Increase the number of bulbs in my home from 4 to 10:
a. 1 for each room,
b. 1 for the main corridor
c. 2 outside over each entrance to my family’s home.
5. Install modern light switches and power outlets.
6. Hide the conduit as much as possible in the walls.
7. Provide AC power for small appliances in my bedroom and the living room through my new inverter, which converts the 12V DC power into 240 V household current.
8. Provide DC power for DC appliances and lighting.
9. Improve safety.
10. Prepare for a hybrid wind/solar system in the future.
11. Install a lightning rod on the windmill.
12. Upgrade the wiring throughout the home from 1.5 mm to 4 mm, which can carry a lot more power safely.
Here is how we accomplished the upgrade, step by step:
1. First we planned the locations of all the new lights, switches and power outlets.
2. Then, we installed conduit and lighting, switch and outlet boxes throughout the house. Where the wall was hard enough, we dug trenches in the walls to bury the conduit using a hammer and chisel.
Ben and I prepare the conduit pipes for installation
3. We also installed conduit from the top of the windmill to the bottom to replace the wire that ran directly from the windmill diagonally through the air down to my room.
4. We dug two trenches to bury conduit:
a. one from the windmill to my bedroom, where the power system is located.
b. the second from the building containing my room to my parent’s main house (only about 2 meters)
5. Next, we ran 4 mm copper wire through the conduits. We used a "fishing tip" to thread wires through the conduits.
6. Then we started installing the compact flourescent bulb fixtures and switches and power outlets. After installing the fixtures, we added the bulbs, 6 watts in most places and 9 watts in the living room and outside.
The new light fixture with the much brighter compact flourescent bulb. Note that the wall has already been patched. This week I’m fixing some other wall issues before coating the walls with white lime, which will reflect the light, making it appear even brighter.
7. Then, we tested if all the wiring, and fixtures worked correctly. Everything operated correctly the first time.
Even after installing the new system, I decided to leave my old, hand-built system of lights and switches so that people could see where I started. It will still work just fine, powered by the older car battery. My from scratch two light switch is at the left of the frame. The new switch is outside the picture.
8. We replaced the old battery with two new deep cycle batteries.
9. With these batteries, it’s necessary to install a charge controller to make sure that the batteries are not overcharged or drained down too far. The controller automatically senses both of these conditions and either cuts off the power coming from the windmill in the first case, or it turns off the power to the house in the second case. Still, we now will have plenty of power every night.
10. We installed and tested a 600 watt inverter, which produced regular Malawian household current (240v) for powering a few small appliances.
11. My cousin Paolo Salemani came to help us replaster the walls to hide the conduits
My cousin Paolo helps patch the walls around the fixtures. This one
is in the kitchen. You can tell because the walls are blackened from
the cooking fires. The smoke is why the kitchen is in a separate building
from the main house. My friend talked to me about chimneys. I’m thinking about that now.
12. We rewired the windmill’s power circuitry. The old way I had it was that the windmill turned a pulley, which turned a bicycle wheel, which powered a small dynamo. I had used a step up transformer to convert this direct current to A/C 240 v to travel down the wire to my house, where I used a step-down transformer to convert it back to DC. We changed this to a direct DC power path from the windmill to the new battery system. This will enable us to add solar panels someday.
13. We showed my family how everything works.
We worked very hard for three days. I learned a lot from working with the team from National Solar. They showed me how to do every step of the process that I didn’t already know how to do, so that I would learn as much as possible. I would like to thank Alfred Maele, the owner of the company and the team who worked with me: Elias Lazaro, Ben Salala, and Steven Machilika.You can reach Alfred of National Solar at email@example.com or 265 01 527 877. My 23 year old cousin, Geoffrey Kamkwamba assisted me with rewiring the windmill.