Tuesday, 9 September 2014


Hi! I’m Helen. I am a graduate of Plymouth University now at the University of Glasgow.

During my time at Plymouth, I was very fortunate to be involved in fieldwork at many fascinating locations with research during my third and fourth year concentrating on the geological complexities of Arctic Norway. Now at Glasgow, I am involved in research for my PhD, titled; Geothermal Energy in East Africa: Rift Geothermics and Fluid Dynamics, with my field location based at Menengai caldera in the East African Rift Valley near Nakuru, Kenya.

Kenya’s position is very advantageous for geothermal energy as the actively rifting East African Rift trends almost north-south cutting through the entire country, north into Ethiopia and south into Tanzania. The active rifting results in the thinning of the crust to (currently) less than 15km in some areas, allowing for the rise of magma to shallower depths. This heat is transferred to the lithologies and in turn transferred to stored groundwater/injected water. Water remains in its’ liquid phase at greater temperatures at depth due to the pressure. However, rapid rise of the fluid under pressure via boreholes causes water to ‘flash’ to steam at the surface. The energy released along with the heat can be used to power turbines for the generation of electricity.

The Menengai caldera started as a shield volcano with an age of about 200,000 years. A two stage collapse occurred 29,000 years ago and 16,000 years ago, resulted in the caldera seen today. It covers and estimated 77km2, has an almost complete rim and steam is often observed rising from the crater floor at multiple locations.

It is estimated that 84% of Kenyan’s do not have access to electricity and those that do find it very expensive and unreliable. The long term plan is for the Menengai Geothermal Project to contribute, along with projects at Olkaria and Longonot, to providing electricity for 500,000 homes, 300,000 businesses and the national grid, allowing Kenya to become an energy independent nation.
The overall aim of this research is to develop detailed conceptual models of the subsurface heat and circulation processes. Some conceptual modelling has been attempted for the area, but appears quite generic.

Geological structures such as faults and fractures are key in any geothermal region as they provide conduits for flow at depth and to the surface. However, details on the structures interacting with the caldera are lacking. Additionally, samples of basalts, gases and fluids with be collected for analysis and will be linked to the types of structures observed in the vicinity of each sample site. Enabling a link between the types of gases and fluids and the structure types and trends.

Geothermal Facts - Did You Know?

1. The definition of geothermal is "geo = Earth" and "thermal = Heat"
2. The world's first geothermal power plant was constructed in 1904 in Larderello, Italy and continues     to generate power today
3. When on MWhr of geothermal power displaces on MWhr of coal fired power, approximately
    one tonne or carbon dioxide emissions is offset
4, Geothermal power plants generate baseload power due to their reliability
5. Geothermal energy is used in more than 20 countries to generate electricity, including the USA,         Japan, Italy, Indonesia, New Zealand, Mexico, the Philippines, Kenya, Costa Rica and Iceland.
6. Kenya is the first country in Africa to generate electricity from geothermal sources
7. Electricity generated by geothermal energy helps conserve non-renewable fossil fuels, significantly     reducing greenhouse gas emissions that pollute the environment.

The aim of this blog is to demonstrate the complexities, adventure, sometimes fun, unpredictable nature of fieldwork. I am nowhere near the most experienced field geologist, but I've done my fair share in the four years I have been at it. There are always surprises along the way. I  hope this blog will contain science, engineering and humour. I hope it might encourage people to think about renewables and why we need to consider them for future power. I also hope to encourage the next generation of budding scientists to engage in geosciences.

Lala Salama from Kenya!

No comments:

Post a Comment