Back To Malembo

Yesterday I went to Malembo and we did 3 major things:

1. Speak to Alex about how operation of the grid has been going.

2. Speak to 3 clients about the service.

3. Explain how the next upgrade of boost/buck converters will help.

Interview with Alex:

Alex is a man who is linked to the Lwemodde youth group and effectively works for them in the small fishing village of Malembo. He runs a number of services. Firstly he runs 3 shops. One for clothes, one for drinks (like water, coke, etc.) and one for utilities. In this town, utilities can be batteries, fishing paddles, superglue, rubber from tire tubes and other random items. Each night Alex uses a petrol generator and inverter to run the town’s cinema. It consists of some camping style pews and a moderately sized cathode ray TV. See photos below. Apparently each night it packs out and he charges only 300 Ugandan shillings (0.12 USD) per head.

Back of the cinema.

Front of the cinema.

To give you a better idea of how the grid looks today, I have taken a video which follows the wires from one client to the power station. You should get a sense for the type of town this is.

Control station. Much more packed now.

Fuse rack #1.

Wires running from the roof.

Quite a few customers are in this direction.

In the interview, Alex first gave me something to think about. He noticed that some wires were starting to become non-conductive and upon dissection would turn out to have very weak cracked copper threads as well a dust inside the wire which looks like ash. He said this only happens to the negative wires.

            Although I cannot be sure, my guess was that too much current was passing through the negative wires and very slowly breaking them. If you see this post you will see our grid design which has a dedicated wire for each positive line to a lamp but a communal negative for many lamps. We required this design to implement our fuse system to stop clients from drawing current beyond the amount they have paid for. Each lamp draws 135 mA and so I told Alex to put only 4-5 lamps per negative wire. After that he can just send another negative wire. Hopefully this solves the issue.

During the interview I learnt that Alex currently has 10 clients and had more prior to now. In the past he has had to disconnect them due to paying their bills. Alex said that in the first and second week of not paying he would just warn the customer. In the third week he would remove the client’s fuse at the power station and so they would still have the hardware but no light. In the fourth week he would remove the wires, lights and switch. The hardware could then be used on a new client. I think this is a pretty good policy and apparently these threats have turned some people into regularly paying customers.

I asked Anita, who is a coordinator for the Foundation of Sustainable Development, the group and Alex why some customers did not pay. Was it because of a lack of money? The cost is only 300 shillings per day but perhaps this is a lot for some people. They all gave me the same answer which was that everyone has the money for this service but for some it is not a priority. It definitely is a priority for some clients as I'll discuss later but for some they have a different mentality. It was explained to me in this way – some people understand that they have lived there for many years without electric lights and only enjoyed the lights for maybe 1 month. If they get disconnected it’s not such a big deal because they know that they can just continue as they did in the past. I guess that is fair enough but that is an interesting thought when in many cases the Malembo Microgrid service is a much cheaper alternative than other lighting methods.

Next I asked how Alex uses the manual as I was very interested to see the impact of it. I know that Baale, the chief of phone repair, founder and treasurer of the youth group, takes the Lugandan edition manual absolutely everywhere he goes. Lydia believes that he sleeps with it every night. So Alex said that he will refer to it when he forgets something technical. I asked for an example and he said the most frequent thing he looks up is the section explaining how to use the volt meter. This makes sense since he has to use the meter a lot to check on the system’s health and also wire people up. Great to see that the manual is useful and the Lugandan translation was worth it!

On that - I was speaking to my host brother (grade 10) last night and asked if he knew of any science books which are in Lugandan. He said that he had never seen one and I know that in university they use only English textbooks. I have a feeling that our manual is the only Lugandan book on electrical engineering that exists.

Client Interviews:

Interestingly, 9 out of the 10 clients are shop owners. Each shop owner has a duel room complex which serves as a shop and a home. Only 1 client has a light exclusively for their home. Some of the previous clients did use a light for their house but they seemed to be the ones who did not pay. Shop keepers are the ones who pay is the general rule.

Below is a bunch of collated results based on all three interviews but differences between each have been outlined. Two of the clients owned food/drink shops and the other client owned a salon.

Each of these clients pay 9,000 shillings per month which is roughly 3.6 USD. Each client, when asked, stated that the price was good but one client playfully told us that “it is good, but it should not go up. Keep it like this.”

The first two clients were quite close to the power station. Probably only 20 meters of cable was needed between their light and the battery. They both said that the light was bright enough for their purposes. The third client who is very far away (bearing in mind that this is a 12 V grid) said that is also bright enough which I did not expect. I assumed the voltage drop across the wires would have kicked in enough to cause a decent loss of brightness.

When asking about a negative of the service one of the clients stated that after a cloudy day/period the lights can be quite dim and so fixing this would be very helpful. Alex does not charge for nights which give very dim lights and in fact will sacrifice phone charging services in the day if it is cloudy to preserve as much energy as possible for the lights at night since those are under written contract. I really like this sort of customer care that Alex gives.

Before these lights were installed one client used a kerosene lamp each night and the other two used a torch (“flash light” for the North American folk). The client needed 2 kerosene lamps each night. One for the shop and one for her bedroom which cost her a rough 1,000 shillings per day in kerosene and each lamp costs 11,000. Considering she now pays 9,000 per month this is far better. The other two clients used torches that cost 4,000 a piece and would cost 400 shillings in batteries each day. This is 12,000 shillings per month and so again the microgrid is cheaper. It was noted that the mircogrid’s LED light was better because it lights up a very wide area while the torch was quite directional and irritating to use because you had to move it around a lot which was a hassle. Also, apparently these torches were quite prone to breaking. Probably yet another case of dumping ultra-cheap Chinese products.

There is a clear health benefit by allowing someone to not have to use a kerosene lamp every night of their life. Additionally there may be an environmental benefit by giving consumers an alternative to buying small batteries every day for a flashlight however I don’t like to make such judgments because the microgrid on the other hand uses solar panels, wires with plastic sheaths and a lead-acid battery. Fabrication of solar panels is intensive and lead-acid batteries are pretty tough to recycle. Who knows which model is more environmentally friendly?

Both of the shopkeepers who had the food and drink shops said that they used to close between 7 pm and 10:30 pm.. Now they pretty much always stay open till midnight. The salon owner also confirmed that staying open later was easier and all three clients agreed that more customers come at night when the place is well lit up. On shop owner stated that she earns 45,000 shillings extra per week since the light was installed. This, on top of the money saved on batteries for her torch, means that she has an additional 183,000 shillings per month which is 73.2 USD. This is possibly the most impactful statistic that I collected.

The client with the salon noted that although there lamp is bright enough, the few people who have private solar panels in this town have very bright lights. This is an alternative available to the more wealth villagers.

Other Notes:

As we walked around Alex pointed out a set of wires to us that he wants to move to higher rooftops or inside the houses they run over. The threat at the current stage, where the wires are quite low, is theft. Some people have been stealing the wires and some of the sugar connectors we used to splice together wires. I asked what people did with the wires and apparently people use them for rope on their fishing boats (remember these are sort of large canoes) or even an ad-hoc switch for their outboard motors.

System Inspection:

The system in Malembo was in great shape. When I visited it was a sunny day and it was halfway through the day. The battery had already approached a point close to full charge. I measured a voltage of 13.25 V across the terminals and this was with a load of 6 phones on charge. The solar panels still gave a steady voltage and were measured at 19.54 V. All the connections looked solid. Sugars were being used and connections which were bearing lots of current used double wires. The racks of fuses were still in order and apparently only 1 fuse blew during the whole time – 6 months now. The cause is not known but at least this means that we have not had people trying to connect clandestine loads to the grid without permission.

Explaining the Boost and Buck Converters:

This sort of technology and why it is important was explained in this post. I do not have the circuits here yet but a demo pair come in the mail soon which I can use to demonstrate to them.

Junior explaining to Alex what the boost and buck converters will do.

Junior going over the diagram.

Other members and Baale looking on.

What was also discussed was how they physical implementation of these circuits would go. Fuses cannot go on the communal 32 V side of the grid and so fuse racks will need to be placed at the location of the buck converter which will take the voltage back down to 12 V. Housing the fuses and buck converter in a remote location will be tricky considering that we have already experienced theft. One possibility is putting the hardware in a locked bock on the very peaks of a roof. Alternatively, if there is a house which belongs to someone trust worthy we may just put the circuitry there. Perhaps we will offer them a free light with no bills. That will cost us very little especially since they will have the step down converter right there at their place. I am letting them think of a way to deal with this issue and I think they will be able to after some planning and thinking.