Lower river flows are expected to curb hydropower generation as irrigation needs soar
p>ACCRA, Ghana (AlertNet) – Acute water shortages in Ghana linked to climate change could see the West African country become one of the world's water-stressed nations by 2025, according to a study by researchers who say urgent adaptation measures are needed to help Ghanaians cope with dwindling water supplies.Water stress - which occurs when demand for water exceeds supply during a certain period or when poor quality restricts its use - not only affects individuals' access to water for drinking, cooking and washing but also impacts farming, power generation and economic growth.
Ghana is forecast to experience a general reduction in annual river flows of 15-20 percent by 2020, rising to 30-40 percent by 2050, according to the study by Ghana's water research agency, the Water Research Institute, part of the Council for Scientific and Industrial Research.
As a result, hydropower generation is set to fall by 60 percent by 2020 while demand for water irrigation is forecast to rise by 40-150 percent by the same year.
"Considering the effects of climate change that we are currently experiencing in Ghana, water scarcity is most likely to worsen in many parts of the country in the future," said the institute's lead research scientist Barnabas Amisigo.
The impact of climate change is already being felt across the country in the form of rising temperatures, dried-up rivers in the dry season, increased rainfall, storms, rising sea levels and intensive flooding, he said.
"Climate change comes with great challenges for water management in Ghana. Adaptation and innovative management will be a necessary response."
Potential adaptation measures may include changes to the design of water facilities, new decisions on planning and allocation of resources, and mass education programmes to ensure more careful use of water by the public, he added.
REDUCED POWER GENERATION
Shortages will also lead to a deterioration of the quality of freshwater and to reduced power capacity.
"Expected floods will carry pollutants into water bodies causing siltation, which restricts their use for hydroelectric generation and for cooling of thermo-electric power plants," Amisigo explained.
This will put further constraints on water availability and electricity generation at a time when demand for energy is growing.
Electricity generated by hydropower using freshwater sources has increased by about 120 percent over the last 45 years.
But scientists fear hydropower is vulnerable to global warming, due to rising demand for water from other sectors.
"Competition for water for use in hydropower generation and for farming along river banks is expected to worsen in the future due to the effects of climate change," Amisigo added.
Faced with water scarcity, Ghana must invest to expand its power generation capacity to meet growing demand and to be able to meet its projected economic growth rate of 6 to 8 percent for 2011, he said.
NEW POLICY FRAMEWORK
Ghana's government, seeking to manage the risks of climate change, believes appropriate policies and regulations are needed to create a more conducive environment for investment in power generation. It has drafted a climate change policy framework to try to achieve this.
"Part of the long-term vision of the framework is to help adapt to climate change and also mitigate the effects of climate change on the country's development," said Edward Omane Boamah, deputy minister for environment, science and technology.
The government intends to increase Ghana's electricity generation capacity from 2,000 megawatts per year at present to 5,000 megawatts per year by 2015 to meet the projected demand for electricity, he said.
"The government's policy objective is to increase development of renewable energy technologies based on wired mini-hydropower, solar photovoltaic and thermo-electric power plants based on natural gas," Omane Boamah added.
Expanding wind, mini-hydropower and solar technologies is a short- to medium-term objective. Thermo-electric power plants based on coal and nuclear power plants are expected to supply the bulk of the country's electricity requirements in the long term, he said.
Nevertheless, climate change also poses challenges to future investment in new technologies. Renewable energy technologies like solar, for example, could be affected by changing weather patterns.
"Increased cloud cover in the future due to climate change will reduce output (of solar technologies) and affect their financial viability," Omane Boamah said.
Ghana, like other African nations, is battling to expand power generation in the face of the effects of climate change, while also having to deal with high global oil prices.
Worsening climatic conditions have caused erratic rainfall across the continent, leaving reservoir levels below normal level. Poorly protected watersheds have also contributed to the problem.
This has severely affected the generating capacity of hydroelectric power dams in eastern and western Africa, weakening already fragile energy sectors and forcing governments to spend their limited resources on emergency generation capacity. This emergency capacity generally relies on fossil fuels that emit greenhouse gases, thereby aggravating climate change.
Suleiman Mustapha is a business journalist based in Accra.
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