NOTE: See major new study subsequently published in January 2012, here.
Around 22,000 fishermen live at the Tanzanian shore of Lake Victoria and earn their livelihood catching a small fish called Dagaa. In order to attract the Dagaa, the fishermen use pressurized kerosene lanterns mounted on top of small wooden floats. Each of these lanterns burns about 1 to 1.5 liters of kerosene per night of fishing. They fish around 25 nights per month, depending on the seasons. Per night, they operate the lanterns between 8 to 12 hours each night while fishing.
Consuming about half of the fishermen’s earnings, the use of these lanterns seriously impedes economic development. The dependence on kerosene leaves fishermen vulnerable to the price volatilities and uncertainties associated with this fuel.
In addition to this, the total annual combustion of about 8,000 tons of kerosene is associated with 25,000 tons of CO2 emissions to the atmosphere. Furthermore, during rough fishing nights some of the kerosene spills into the already highly polluted lake, which remains one of the main drinking water sources for the local population.
Similar night-fishing techniques are employed all around the lake and to our knowledge are common in developing countries all around the world.
There have been several attempts to address this issue and replace the kerosene lanterns with more efficient lighting devices. We dealt with this problem for the first time in 2009, when we conducted some fieldwork in Mwanza, Tanzania. We developed an initial prototype lighting system based on locally available items (see photo below). We employed a waterproof Sundaya Multilamp (CFL), which was rated at 1000 lumens, plus solar batteries (12V, 24Ah) that we charged with an over-sized 50W Solar panel to ensure full recharging even on cloudy days. Due to the heavy battery we had to supplmeent the traditional float. This system was able to meet the demands of the fishermen with respect to the catch volume they were used to from the kerosene lanterns.
Another CFL-light we tested provided only 600 lumens, which did not meet expectations. Concerning the required light putput, it shall be noted that the much of the light is wasted because it is either reflected by the float or on the water surface.
Most fishing lamps that are employed in the Western world are submersed and emit green light. While we had no chance of testing for the color yet, submersed lights were less efficient (in terms of fishing success) than if they were mounted on floats above the water level.
The task of replacing kerosene lanterns with more efficient lighting technologies faces several specific challenges. On the one hand, a new system needs to provide high lighting output, while being reliable and operating for 8 to 12 hours daily. This places some constraints on the battery employed. For the future, the use of LED-technology thus seems to constitute a promising approach.
That said, the initial cost of a new system is critical. The first prototype had a cost of $365 (including the solar panels), which had a payback time of less than 12 months. This is an indicator of the great potential of a new lighting solution. Some fishermen explicitly stated their ability to afford the new system even at this price. However, given a large variance in income among the fishermen, it is clear that initial cost remains a major obstacle. Certainly costs could be lowered by shifting to LED systems. Micro-finance products seem appropriate to address this problem. It seems crucial to us that throughout the process of distributing and financing the system local structures are used. These structures could include fish traders, fishing camp chiefs and boat owners.
This is a crosspost from the Lumina Blog: http://offgridlighting.posterous.com/91432426.
We (Tim Gengnagel and Philipp Wollburg) have spent time in Tanzania, working with night fishermen who use kerosene lanterns to attract fish to their nets. Long operating hours, plus high fuel-use rates of these pressurized lanterns result in 1 to 1.5 liters of kerosene use per lamp each night provide a strong case for conversion to LED sources. Sadly, climate change (to which kerosene lamps contribute), is hampering fish yields in this part of the world.
We are now working with the Lumina Project and and have returned to Tanzania in March 2012 to clarify the technology needs and communicate these to off-grid lighting manufacturers interested in this market.
Siemens Press Picture