African Rift Geothermal Development Facility

[phantom power]

Kenya has 14 geothermal sites with the potential to produce between 7,000 megawatts and 15,000MW of power. To put that figure in context, Kenya currently generates 1,350MW of electricity from all sources (including 210MW from geothermal).

...

Last year, the African Rift Geothermal Development Facility (Argeo) was established to help accelerate the pace of geothermal development in six countries: Kenya; Tanzania; Ethiopia; Eritrea; Djibouti; and Uganda.

"Argeo's directive is to promote geothermal development through decreasing the risk associated with exploration and development of geothermal," says Meseret Zemedkun, the project manager of Argeo.

...

In the next five years, it plans to establish a regional database on geothermal resources, increase the number of skilled workers in the industry, and help establish a clear regulatory framework for individual countries and the region.

http://www.thenational.ae/thenationalconversation/industry-insights/energy/something-to-get-steamed-up-over

[hobbit709]

1. What happens when the rift finally opens?

[rfranklin]

3. It fills with ocean water just like the Red Sea...

http://en.wikipedia.org/wiki/Great_Rift_Valley

[TheWraith]

2. Cool.

Geothermal hasn't gotten a ton of attention, but it seems to be increasing in profile. In a way it has a lot in common with hydro power. Limited locations, but high generating potential and low maintenance.

[phantom power]

4. I've been wondering if modern drilling tech could expand the range of feasibility.

If you drill down around 3-4 kilometers you can theoretically boil water almost anywhere on earth, which is only about 1/3 the depth of the deepest oil well. I assume those depths and lower temperature gradient would make geothermal less energetically feasible, but perhaps there is middle ground closer to geologically active regions.

[Bob Wallace]

5. Hot rock geothermal...

Or "enhanced geothermal" where multiple holes are drilled, water inserted in one and hot water harvested from the other holes is a technology not yet perfected.

Geothermal needs larger diameter holes than are used for oil Larger diameter bits are easier to get stuck and there are issues with keeping the bits sharp. It may have to do with the type of rock that needs to be drilled, the details escape me at the moment.

Once the holes are in the rock at the bottom has to be fractured. Does "fracking" ring a bell? Hot rock geothermal does not use the chemicals that are used for natural gas fracking, but the process can trigger small earthquakes.

There is some hot rock activity being carried out in Australia. They're far enough away from towns so that no one is overly concerned about any shaking. If they can make their system work then it's likely we'll see more happening elsewhere.

I don't think hot rock geothermal would work absolutely everywhere. It does require a certain type of rock formation at depth, but it would work a lot of places.

One of the interesting techniques for drilling is being tried by a company called Potter Drilling. They are using jets of extremely hot water to crack and break up the rock underneath their "bit". The water then washes out the bits of broken rock. Because there is no physical bit to get dull their process goes much quicker. No need to extract the very long lengths of drilling pipe to get the bit out.

Here's hoping....

[phantom power]

6. bitless drilling seems like a cool technology

I can see how that would save a lot of fooling around