Hydro power under threat as Zimbabwe faces crippling droughts

Women and children sell firewood in the city of Mutare.

“I use firewood for cooking during power outages,” Mazanga said dejectedly: “Cooking is now a nightmare”.

Like the majority of people in Zimbabwe, Mazanga said she now depended on firewood for cooking during electricity outages.

The electricity outages in the country became worse in December last year some neighborhoods going for upto 20 hours a day without electricity.

But Mazanga, a mother of three, seemed oblivious of the dangers of household air pollution which according to experts is one of the leading causes of death in developing countries.

Mazanga is vendor on the streets of Zimbabwe’s eastern border city of Mutare.

“Life is really tough. At times I use discarded dirty plastics to make fire for cooking,” she said.

However, according to the Global Alliance for Clean Cookstoves, an international private-public sector alliance working towards the adoption of clean and efficient cook stoves and fuels, upto 4.3 million deaths a year the world over are caused by household air pollution.

The alliance said household air pollution was the number environmental risk factor for the burden of diseases in the developing countries, responsible for a higher burden than unclean drinking water and poor sanitation.

And fears abound in Zimbabwe that the growing number of people resorting to firewood for cooking in urban and rural areas would result in a spike in deaths related to household air pollution.

Zimbabwe depends mostly on hydroelectric power from Kariba Dam, and the 2014/2015 drought coupled with the current El Nino induced drought has resulted in water levels in the dam dropping to critical levels.

Kariba Hydro Power Station was by end of January this year generating less than 400 megawatts (MW) instead of the installed capacity of 750MW, due to low water levels in the dam.

And according to the Zambezi River Authority, which superintends over the Kariba Dam, water levels had declined to 12 percent by early this year.

The country also generates electricity at Hwange Thermal Power Station and three small other thermal stations in Harare, Munyati and Bulawayo. And there are also independent micro hydro power stations dotted around the country’s Eastern Highlands.

Zimbabwe needs 2 200 megawatts a day but is currently generating around 1 300 megawatts a day. By January this year, Zimbabwe was importing 300 megawatts from South Africa which resulted in an improvement in electricity supply.

However, the Zimbabwe Electricity Supply Authority was also planning to increase electricity tariffs from by 49 percent from 9,86 cents to 14,69 cents per kilowatt hour. The power utility said the hike was cost reflective and necessary to augment emergency power imports.

And as the droughts bite deeper, independent mini hydro power plants in Zimbabwe’s Eastern Highlands have also been hard hit by water shortages.

One such micro hydro power station is Chipendeke located about 70 kilometres south of the eastern city of Mutare near the border with Mozambique.

A visit by this journalist to Chipendeke Micro Hydro Power Station, up the Himalaya Mountains in Eastern Highlands, late January this year revealed that power generation had been temporarily suspended due to water shortages.

Water levels in Chitora River which supplies water to the mini hydro power plant had now gone so low forcing the temporary suspension of electricity generation.

A small building which houses the plant’s power turbines was under lock and key and looked deserted; the generator was switched off.

Phillip Muwungani, a villager at Chipindeke Resettlement Scheme, said hydro power station had been affected by the low levels of water in the river.

“We use the same water for irrigation and electricity power generation. Water levels are very low and the electricity generation was temporarily stopped (on 27 January 2016). The situation is very bad,” Muwungani said.

“Our priority at the moment is water for the irrigation scheme. We are using the little water available to irrigate our crops,” he said.

Another villager in the same area, Joseph Nakai, said the power outage had affected a local school, clinic and business centre.

“We hope things will improve if we receive some rains. The clinic needs electricity to preserve medicines,” he said.

Chipendeke Micro hydropower project and a neighboring Himalaya Hydropower project are part of the sustainable energy initiative spearheaded by Hivos, Zimbabwe Regional Environment Organization, Practical Action and the Zimbabwe Energy Council.

The critical shortage of electricity in the country has a serious effect on virtually all sectors of the economy in the country.

But as the country explore options for clean and renewable energy, independent economist and energy expert, Eddie Cross said Zimbabwe was not suited for wind power generation as there were few sites with sufficient wind.

However, Cross who he is also a legislator for Bulawayo South, said the country was investing quite heavily in solar energy and within two years Zimbabwe would get about 20 percent of its electricity from solar.

He was however quick to add that: “The problem is that storage is very costly and with a limited life span at present and therefore we will still have to rely on coal for our base load and perhaps gas”.

Cross said: “But for our peak demand periods hydro remains our best and least cost option – Kariba Hydro Station produces power at 1,5 cents a kilowatt hour (KwH)at the wall, coal 8 to 12 cents, solar 20 to 30 cents. Providing we use hydro as a peak supplier and not as base load, we should be OK at 85 percent of the water in the Zambezi River (Kariba Dam)”.

In a recent study –Worldwide Electricity Production Vulnerable to Climate and Water Resource Change-(http://www.iiasa.ac.at/web/home/about/160104-water-energy.html) it emerged that climate change impacts on rivers and streams may substantially reduce electricity production capacity around the world.

And the study calls for a greater focus on adaptation efforts in order to maintain future energy security. “Hydropower plants and thermoelectric power plants—which are nuclear, fossil-, and biomass-fueled plants converting heat to electricity—both rely on freshwater from rivers and streams,” said the lead researcher Michelle Van Vliet, a researcher at the International Institute for Applied Systems Analysis (IIASA) in Austria and Wageningen University in the Netherlands, who led the study.

“These power-generating technologies strongly depend on water availability, and water temperature for cooling plays in addition a critical role for thermoelectric power generation.”

The study revealed that climate change impacts and associated changes in water resources could lead to reductions in electricity production capacity for more than 60 percent of the power plants worldwide from 2040-2069.

According to the study hydropower and thermoelectric power currently contribute to 98 percent of electricity production worldwide.

The study expands the research to a global level, using data from 24,515 hydropower and 1,427 thermoelectric power plants worldwide.

“This is the first study of its kind to examine the linkages between climate change, water resources, and electricity production on a global scale. We clearly show that power plants are not only causing climate change, but they might also be affected in major ways by climate,” saidIIASA Energy Program Director and study co-author, Keywan Riahi.

“In particular the United States, southern South America, southern Africa, central and southern Europe, Southeast Asia and southern Australia are vulnerable regions, because declines in mean annual streamflow are projected combined with strong increases in water temperature under changing climate. This reduces the potential for both hydropower and thermoelectric power generation in these regions,” said Van Vliet.

The study also explored the potential impact of adaptation measures such as technological developments that increase power plant efficiency, switching from coal to more efficient gas-fired plants, or switching from freshwater cooling to air cooling or to seawater cooling systems for power plants on the coasts.

“We show that technological developments with increases in power plant efficiencies and changes in cooling system types would reduce the vulnerability to water constraints in most regions. Improved cross-sectoral water management during drought periods is of course also important,” Van Vliet said.

However, Van Vliet said: “In order to sustain water and energy security in the next decades, the electricity focus will need to increase on climate change adaptation in addition to mitigation.”

This content was produced with support of the Access to Energy Journalism Fellowship and Discourse Media www.http://discoursemedia.org/