Time filter

Source Type

Njue L.,Geothermal Development Company
Transactions - Geothermal Resources Council | Year: 2012

Plate boundaries are part of the earth's tectonic system. Divergent plate boundaries are zones where lithospheric plates move apart as a result of tensional forces causing melting as a result of pressure decrease. Typically, they are characterized by tensional stresses that naturally produce long rift zones, normal faults, and basaltic volcanism. A comparison is made of cuttings from geothermal wells located within a continental divergent margin in Kenya and samples from an oceanic divergent margin Iceland. The stratigraphy of Menengai well MW-02 is mainly composed of trachytic rocks whilst samples from Hellisheidi HE-27 based on binocular observations aided by petrographic thin sections and XRD analysis are primarily basaltic. The comparison of cuttings from Menengai and Hellisheidi show dissimilarity in geology mainly as a result of the type of divergent boundary.

Kiruja J.,Geothermal Development Company
Transactions - Geothermal Resources Council | Year: 2012

The growth of industries is dependent on the availability and affordability of energy. However, conventional energy sources such as fossil fuels are getting depleted and their price is increasing rapidly due to market forces and world politics. It is therefore necessary to consider alternative sources of energy and geothermal energy is a potential option. Geothermal energy can be utilized for both electricity generation and direct uses such as heating and cooling. The dairy industry in Kenya can benefit immensely from the vast geothermal energy in the country since both dairy farming and the geothermal resources are located in the same region i.e. the Rift Valley region. Furthermore, dairy processing involves both heating and cooling operations, whose energy requirements are within a range for the geothermal resource in Kenya to cater. This paper discusses some of the dairy processing operations which can utilize geothermal energy and the appropriate technology which can be applied for each operation. The energy demand and the cost of each operation are also discussed.

Mutonga M.,Geothermal Development Company
Transactions - Geothermal Resources Council | Year: 2012

Silali is the largest and trachytic caldera volcano in the axis of the northern Kenya Rift Valley. This paper describes the results from examination of existing data and detailed geological exploration by the geology team of GDC. The study involved geological mapping of the rock formations, structural mapping and geothermal manifestations well as hydrogeological and volcanological studies of the volcano and sampling of rocks for thin section cutting and petrographic analysis. Fieldwork was carried out in the month of May and July 2010. Basalt is one of the most common types of lava in Silali, manifested mainly as flank fissure basalts and flood basalts. Basalts are aphiric or porphritic and vesicular. The Silali Trachytes are both silica-oversaturated and silica under saturated. In the post caldera group increasing differentiation is thought to have resulted in progressive silica under-saturation. The Blackhill Trachytes are among the youngest lavas are critically under-saturated with respect to silica. The latest activity from a satellite vent on the northern slopes of Silali is basaltic in composition and was erupted about 200-300 years BP. The presence of a still active heat source to sustain a geothermal system(s) indicates that there is a geothermal resource in the area that can be commercially exploited.

Wamalwa H.M.,Geothermal Development Company
Transactions - Geothermal Resources Council | Year: 2011

Given the strength of commodity prices in recent years, concerns over energy security and widening adoption of carbon emission pricing, renewables are well positioned to play growing role in global energy mix. Geothermal energy is on the face of it. By harnessing the heat of the earth, geothermal power plants tap into a virtually inexhaustible and continuous source of energy, using a small footprint facility to provide baseload electricity that is virtually CO2 and waste free. Geothermal projects today center on the exploitation of hydrothermal resources- reservoirs of naturally occurring water. This could change with Enhanced Geothermal System (EGS), a new form of geothermal exploitation being tested in areas that are not hydrothermal. This paper discusses the prospect of Enhanced (or Engineered) Geothermal System as a means to the baseload power generation. It also focuses on the technology behind creating engineered reservoirs; it reviews the environmental impacts as well as possible mitigation measures.

Mutonga M.,Geothermal Development Company
Transactions - Geothermal Resources Council | Year: 2013

Paka is a complex multi vent low basalt-trachyte volcano dominated by a young central caldera at the summit, which is 1.5 km in diameter. It is situated 25 km north of Lake Baringo and 15 km east of Nginyang' Village. The volcanic complex is dotted with a number of smaller satellite volcanic centers, which are linked to the main volcano by linear zones of basalt and trachyte cones and eruptive fissures. The main heat source(s) for the Paka geothermal system are the trachyte-basalt intrusive or intrusion complexes underneath the volcano. These bodies are long-lived and are fed by up-welling from time to time of fresh magma from depth. Altered grounds, fumaroles and well-crystallized sulphur deposits along faults within the caldera and the Eastern crater indicate that the faults are deep-seated and are magmatic in provenance. At a local scale, the NNE-SSW and N-S trending faults and fractures are essential in enhancing permeability in the prospect area. The subsurface rocks of Paka prospect wherein the geothermal reservoir is expected to be situated are made up of mainly faulted Miocene lavas. The combination of local and regional structures has enabled fracturing in the reservoir rocks to allow for movement and retention of geothermal fluids. The cap rock for the system is expected to be the Plio-Pleistocene lavas and their associated pyroclastics.

Discover hidden collaborations