Kenyan Lakes And Geothermal Power  

Kenya's "Daily Nation" is wondering if geothermal power is the cause of the decline of the country's lakes - Could this be true?.

Eddy Mwasi believes there is a direct link between the drying up of Lake Naivasha, Lake Nakuru and Lake Elmentaita and the thriving Ol Karia geothermal plant. Says he: “What is the source of the steam that drives the geothermal plant other than the waters of the three lakes? The rate at which these lakes are drying up corresponds to the growth of Ol Karia. But the source of the steam water is not limitless. As the lakes dry up, the plant is also threatened?

I would be alarmed if this is the primary cause of the decline in water levels (given my fondness for this energy source), so lets take a look at what is happening in Kenya.

The BBC described the potential for geothermal power in Kenya a few years ago - Kenya looks underground for power.

Experts from the United Nations say if this geothermal energy were harnessed, it could provide power to some of the world's poorest nations. Eritrea, Ethiopia, Djibouti, Uganda, and even Zambia have the potential to tap in. But so far, Kenya is the only nation which has made headway. ...

The Ol Karia station is the continent's biggest geothermal power-generating plant. It takes its name from a nearby volcano, which erupted 150 years ago and is still active. There are 22 wells across the site, piercing the Earth's crust, and tapping into rock as hot as 345C deep below the surface.

Silas Simiyu, Ol Karia's development director, says: "Since geo-thermal is an indigenous energy source, we should start with what is ours - not with importing these petroleum products." But even Kenya has been slow to exploit this energy source. The Philippines started geothermal work in the early 1980s - the same time as Kenya - but now generates 20 times more power.

Mr Simiyu attributes the sluggish development to bad policies and bad politics. In the past, hydroelectric dams - the main source of the country's electricity - have been much more appealing to Kenya's rulers. Grand projects, built in a politician's constituency, help generate employment and shore up electoral support.

According to Mr Simiyu, the crunch came during the big drought of 2001. Kenya was plunged into darkness for hours every day as the dams dried up. The power generated by geothermal means saved the country.

In 2002, a second power plant at Ol Karia started work. By 2010, a third should have been completed. This is part of an upsurge of interest in geothermal power across the region. In Uganda, the government is looking into "mini-geothermals", power plants which would generate enough electricity to light up remote villages. ...

The potential for Kenya's businesses can be seen at Oserian flower farm, close to Lake Naivasha. The company says it has the first geo-thermally heated greenhouses in the world. Engineering director Bruce Knight, reckons that the product - long-stemmed roses, destined for Europe - has already improved as the company can now afford to heat its greenhouses through the night.

The company was lucky because it had two existing wells on its land, drilled by the national power company, Kengen. Kengen abandoned the wells, believing they lacked potential. But after investigation, Oserian decided the wells might provide enough energy to power a flower farm.

They bought a ready-to-assemble geothermal plant from Israel - estimating that the million-dollar costs would repay in four to six years. The flower farm is now almost entirely dependent on geothermal energy, which is cheaper and more reliable than the national grid.

Wildlife Extra reports that Lake Naivasha has been in decline for 3 decades, with argiculture bearing much of the blame - Lake Naivasha is threatened by rampant water usage..

Lake Naivasha, Kenya's second largest lake, is an ecosystem in crisis. The lake level has dropped by three meters from its maximum, the area has shrunk to half its size, and precious wetlands are degraded beyond recognition. At the Fourth World Water Forum, in Mexico City, Earthwatch scientist Dr. David Harper of the University of Leicester presented evidence of three decades of ecological decline at Lake Naivasha and made urgent recommendations for the lake's sustainable future.

'Lake Naivasha was once considered one of the world's top ten sites for birds and a paradise of clear water, with beautiful papyrus and water lily fringes,' said Harper, principal investigator of Earthwatch's Lakes of the Rift Valley project. 'A haven for African wildlife and a major source of water for the lakeside's quickly growing population, the health of Lake Naivasha is critically important.' The ever-smaller lake is becoming an over-enriched muddy pool, which shortly will become unusable through the development of toxic blue-green algae blooms. Its inflowing rivers, formerly sparkling and permanent, are now muddy and unpredictable.'

Naivasha is being sacrificed because we require too much water. Almost everybody in Europe who has eaten Kenyan beans, Kenyan strawberries and gazed at Kenyan roses has bought Naivasha water. Tourists and hotel guests have drunk it, the Ol Karia geothermal power station is run by it, and local people depend on it for their daily lives.

Harper urged the support of three objectives to save Lake Naivasha from ecological collapse. First, an upper limit on basin extraction must be agreed upon and shared equitably and transparently, counteracting the dishonesty of over-use and ignorance of waste. Second, the lake wetlands and riparian vegetation in the basin must be restored to functionality. Finally, an educational campaign must be launched encouraging the principles of ecohydrology and the real value of water to all basin inhabitants.

WorldLakes.org points out that lake levels have fluctuated dramatically over the years and that the goethermal plant gets its water from groundwater rather than directly from the lakes - Managing Lake Naivasha.

Being a shallow lake with gently sloping shores, Naivasha’s shape and size have always been subject to great seasonal variations. When the explorer Joseph Thomson marched through the area in 1884, the lake was virtually dry, with cattle grazing around a small pond in the centre of the present site. A decade later, the lake was lapping at the cliff-face above the present-day railway line – more than 10 meters higher than today’s level.

With such huge fluctuations, massive evaporation, widespread abstractions by its farmers and flower growers, and – more worrying still – by smallholders and dairy farms on the rivers feeding the lake, many Naivasha residents believe a return to Thomson’s ‘pond’ is inevitable, even natural. ...

The new environmental awareness that appears to be sweeping through Naivasha has gained another high-profile supporter in the Kenya Electricity Generating Company, KenGen, whose Ol Karia power plant is a prominent lakeside landmark. There can be little argument against the geothermal plant, which remains one of Kenya’s most environmentally friendly sources of power and is expected to almost double its contribution to the beleaguered national grid over the next 20 years. However, fears do remain about the impact of drilling on the underground water flows and aquifers feeding the lake, and the LNRA has called for continuing monitoring of the situation.

KenGen maintains that its use of water for drilling the geothermal wells and operating the plant have a negligible effect on lake levels. Martin Mwangi, the Geothermal Development Manager, says the plant relies on steam extracted at great depths – between 1,000 and 2,500 meters - whereas the aquifers delivering water to the lake are less than 200 meters deep.

“The closeness of the Olkaria geothermal system to Lake Naivasha and the obvious use of natural steam in power generation give a very erroneous impression that the steam and the hot water are derived directly from the lake,” Mwangi says. “It is also not obvious to people that the ground itself is a huge reservoir capable of driving the geothermal systems in the Kenya Rift without a surface lake. We think the water we exploit is primarily derived from the Rift flanks where fractures penetrate between three and seven kilometers into the hot rocks, allowing the water to reach these rocks and rise back to the geothermal reservoir.”

While it seems unlikely that the geothermal power plants are the primary cause of shrinking lake levels, AllAfrica.com reports that there are other concerns facing the expansion of Kenya's geothermal power industry - Plans for Power Plant At Crater Creating Deep Rift.

The proposal to establish a geothermal power station in the Menengai Crater in Nakuru is being challenged by environmental conservationists who want the crater to be preserved as a tourist attraction.

Nakuru industrialists, on the other hand, argue that the generation of geothermal power will go a long way in helping meet the country's power needs. Business owners say they have lost expensive equipment as a result of power surges while others have had to buy generators to sustain production when power cuts occur. They say that the diesel power generators have made production more costly and uneconomical.

Textile manufacturers in Nakuru town say they are losing out to competitors in Egypt and South Africa where electricity tariffs are low and they can afford to price their products low. Mr M.S. Shah of Londra Textiles said that there was no likelihood of the textile industry recovering, despite government efforts to address the industry's issues, unless electricity tariffs were lowered.

Other manufacturers say they are unable to meet export delivery schedules when power is rationed during the dry season. Mr J. Bedi of Bedi Investments told the Sunday Nation that the rising cost of electricity and fuel was impacting negatively on production. His firm, which previously paid an electricity bill of Sh2 million per month, now pays Sh3.1 million.

Mr Bedi said the high cost of production was likely to force investors to relocate to other countries where electricity tariffs were low. Already, many manufacturing industries said they have reduced staff numbers to stay afloat.

"The establishment of another geothermal power station will go a long way in alleviating the electricity shortage this country has been having over the years. The Menengai Crater has been lying idle since independence. Let KenGen expedite the power generation," said a Nakuru industrialist. He added that since the Ol Karia Power Station and the Hell's Gate National Park have a symbiotic relationship, there is no reason for conservationists to think a geothermal power generation plant in the Menengai Crater would be harmful.

KenGen runs Africa's biggest geothermal power station at Ol Karia in Naivasha where it has many geothermal wells.

A former chairperson of the Nakuru Business Association, Mr Peter Kinya, said that several European countries had well-developed geothermal power generation stations that did not compromise the quality of the environment, arguing that the geothermal station would occupy only a small portion of the 90-square kilometre crater.

Hydro-geologist Mwangi Gichuki said he could not dismiss the many benefits that the country stood to gain by establishing a second geothermal station. "We need cheap power but KenGen must also ensure that the communities living in the neighbourhood of the crater are not exposed to poisonous chemicals such as sulphuric acid which forms when emissions such as hydrogen sulphide mix with water," he said.

He said that the wells which could be a kilometre deep were also likely to affect the hydrology of the area, considering that a number of boreholes are also being sank at Ol Bonita in the neighbourhood of the crater. "It is a catch-22 situation. We need electricity and at the same time we must ensure that the health of the communities in the neighbourhood is not compromised," Mr Gichuki said. The Menengai Crater geothermal station is expected to produce about 140MW.