A study to determine the influence of penstock outlet, number of v-blades, flat blade lateral twist angle and the hub to blade ratio on the performance of the Pico-hydro system has been conducted. Five turbine runners with 8, 9, 10, 11 and 12 v-blades were fabricated and tested on an already existing system. A runner with adjustable flat blades was also fabricated and tested for twist angles of 50 0 , 55 0 , 60 0 , 75 0 and 90 0. Runners with v-blades but having hub to blade ratios of 0.3, 0.4, 0.55, 0.65 and 0.7 were also tested. The turbine was connected to 3.9 kVA alternator via a v-belt drive and a 1 Hp pump was used to sustain the flow. The turbine and alternator shaft speeds were measured, and the level of water in the overhead and underground reservoirs monitored. The flow rate, available head and the hydraulic power were computed for each operation. The results obtained indicated that using a combination of a runner with 12 blades and a penstock outlet of 20 mm, 0.55 hub to blade ratio and lateral twist angles greater than 75° combined with penstock outlets larger than 20 mm have the potentials of better performance in terms of power generation. The results of correlation and reliability test using Cronbach's alpha carried out on the data at 95% confirmed these findings. This will be very useful for further development of the system in order to attain implementable status as a clean and decentralized energy source.

The theory of a glazed transpired collector solar air heater in natural convection mode has been developed. This was aimed at generating a framework for the experimental study of the performance of the collector. The theory involved the definition of some of the collector's main geometries, the formulation of the energy balance on the collector and the driving forces within the collector. Dimensional analysis was then applied to the formulations to obtain relationships between important dimensionless groups. The theory of the glazed transpired collector in natural convection mode provides a basis for the development of the collector for application in the areas of space heating and crop drying. This type of collector provides a solution to the challenge of space heating and crop drying at locations where electricity is not available and photovoltaic power is not affordable. It could also contribute to energy savings since it requires no electricity to work.

The field performance of palm fibre insulation board treated with cassava starch solution has been studied. This was done in search of local substitutes for imported insulation materials used in low temperature (45°C -200°C) ovens. Fresh oil palm fibr e was collected from palm-kernel, washed with non-reactive detergent to remove its oil content and dried to constant mass in an oven. The dried palm fibre was treated with 0.2 w/w starch solution, compacted into rectangular boards and re-dried in an oven to constant mass. The fibre bands were then installed in a locally developed oven for the field test. The test involved examining the stability of the thermo-physical properties of the insulation board after baking activities for 4 hours. This was done by comparing the density, physical appearance and thermal conductivity of the board before and after the use in the oven for baking. There were no significant changes in the thermo-physical properties observed before and after use. The results indicate that the palm fibre board is suitable for use as an insulation material in low temperature oven application. Successful implementation of the board could contribute greatly to savings on importation costs of conventional insulation materials while enhancing the safer utilization of a by-product of the Nigerian palm oil industry. Furthermore, this will enhance better environmental conditions and comply with the current clamor of converting waste to riches.

The basic operational parameters of a simplified pico-hydropower system with provision for water recycling were investigated. Five simplified turbine of runner diameters 0.45, 0.40, 0.35, 0.30 and 0.25 m were designed, locally fabricated, and tested in conjunction with five PVC pipes of diameters 0.0762, 0.0635, 0.0508, 0.0445 and 0.0381 m as penstocks. Five simple nozzles of area ratios 1.0, 0.8, 0.6, 0.4 and 0.2 were fabricated for each penstock diameter. The turbines were successively mounted at the foot of an overhead reservoir such that the effective vertical height from the outlet of the reservoir to the plane of the turbine shaft was 6.95 m. A 1.11 kW electric pump was used to recycle the water downstream of the turbine back to the overhead reservoir. The mean maximum and minimum rotational speeds of the shaft of each turbine were measured for each penstock diameter and nozzle area ratio, and the volumes of water displaced in the reservoirs were also monitored. These measured data were used to compute shaft power and system volumetric flow rate for each operation. Dimensionless flow, head and power coefficients, and specific speed were computed and functional characteristics relating them developed. This standard procedure generally used for the analysis of geometrically similar hydraulic machines have been applied to this system and the results obtained will be invaluable in development of the system into a simple, environmentally friendly and decentralized small power generation system that could potentially contribute positively to the energy mix in Nigeria. The possibility of scaling the system to accommodate larger turbine and penstock diameters, and as a result higher capacity alternators exist and is a target for future developments.