Tanzania faces acute electricity energy supply yet with investments in offshore wind and tidal waves projects, the country can turn fortune by generating extra electricity supply and ridding a straight path into a clean energy future.
By Moses Kulaba, Governance and Economic policy center
@climate change , energy transition and COP28 series
According to Global Information Systems (GIS) reports Tanzania has strong offshore winds capable of generating up to 17Gwh and estimated tidal stream power of 133 kW/m. Yet this potential lies idle and unexploited.
At least 60 % (2/3) of Tanzanians lack access to power and in recent years and months, power rations have worsened, lasting for over 12 hours as the national grid suffers from acute shortages due to overloads and deteriorating infrastructure. The situation is worse in 2023 compared to five years ago and has affected Tanzania’s economic production and growth substantively. According to the world bank the cost of power outages in Tanzania cost businesses about 15% of annual sales and millions of dollars to the national economy.
The energy shortage also affects the semi-autonomous territory and tourist hotspot Zanzibar, which is heavily reliant on the mainland Tanzania for its electricity generation and supply. Both Unguja and Pemba are completely reliant on power purchased from TANESCO through submarine cables of 100 MW and 25 MW capacity, respectively.
Zanzibar lacks its own power generation facilities, and electricity is supplied from mainland Tanzania by the 132kV undersea cable. The cable has reliability and maintenance challenges sometimes plunging the entire Island into a total power blackout. As a partial mitigation against this risk, Zanzibar Electricity Company (ZECO) maintains 25MW of grid-connected high-speed back-up diesel generators. Most hotels, offices, industries, and various private sector consumers have their own captive emergency diesel generators to supplement in situations of power outage. However, the cost of maintaining these is high and their constant emission of poisonous fumes during operation is dangerous to the environment. Offshore wind and tidal electricity would help Zanzibar wean itself from over reliance on the mainland’s Tanzania National Electricity Supply Company (TANESCO) as the National grid has been perpetually facing power shortages.
As of the year 2021 Tanzania’s total electricity supply was 1605.86 MW. Peak electricity demand in the country is expected to roughly quadruple by 2025 to 4,000 MW. To help meet this demand, Tanzania is targeting installed capacity of 10 GW by 2025. However, maintenance issues and climate change-induced water shortages have caused a 400-megawatt electricity shortfall in Tanzania, triggering power rationing across the country. For many Tanzanians, it is repetitive cycle of darkness. The sun rises and there is no power. It sets and it’s pitch black – in fact, according to government data at least two-thirds of Tanzanians don’t have access to electricity.
Developing of wind shore and tidal waves electricity generation capacity would be a win-win situation for both Zanzibar and Mainland, as it would supplement the much-needed electricity during peak hours and reduce on the heavy burden imposed on the national grid, providing power to many customers who need it.
Moreover, these projects if developed, would be a game changer for the Country’s energy sector. They would catapult the country long steps ahead of its peers in achieving its energy access goals, and meeting its Nationally Determined Contribution (NDC) Goals on the road to clean energy transition. For this to happen, some deliberate political and policy choices have to be taken.
Why offshore wind and tidal power is important
There are questions about intermittency and whether technology exists to support investment into Tanzania’s offshore wind and tidal wave potential. Our basic analysis suggests that projects of this nature would be viable and worth giving a try.
The United Republic of Tanzania (URT) is the largest country in East Africa, located between longitude 290 and 410 East and Latitude 10 and 120 South. URT has a Territorial Sea of 64,000 km2 and an Exclusive Economic Zone (EEZ) of 223,000 km2, which is about 24 percent of the land area. Tanzania has a total coastline of 1,424 km running along the Indian Ocean, with an average wave energy potential of 7.5KW/m and theoretical potential of 94TWh/y. The coastal population is estimated at 30% of the total population, providing a huge potential for the generated electricity.
Tanzania has both shallow waters close to its coastline which would allow offshore wind projects development under the current technology and an extensive Exclusive Economic Zone (EEZ) off Zanzibar’s shorelines ideal for anchoring deep water floating platforms to allow it to access wind resources at much deeper water depths across its entire EEZ. The government is open and has been encouraging investment in its current EEZ. However its current investment drive has targeted the fisheries sector. With an extended offshore coastline and Exclusive Economic Zone (EEZ) running off Zanzibar, Tanzania has unique advantage compared to its regional neighbors.
From a cost perspective, offshore wind and tidal wave projects are viable. There is much more wind on the shoreline than on land, with an average of speed of more than 50m. Evolution of turbine technology, installation experience has allowed economies of scale and costs of wind power generation has gone down significantly. It is further projected to reduce by 40% over the next decade.
Moreover, the levelized cost of selling power on the market has gone down significantly as economies of scale for wind turbines have grown. The cost of selling electricity has come down to approximately $50/Mwh. Therefore, wind energy now is one of the cheapest generated powers compared to gas combines cycle, coal and considerably cheaper than solar PVs.
Globally, wind generated power is projected to grow as countries ramp up their clean energy generation in line with the road towards net-zero by 2050. This a trend that offshore wind technology will rapidly become cost effective renewable energy technology and a good option that developing countries can consider when developing pathways towards decarbonizing their electricity supply-system.
Tidal energy will also be a good option. Ocean tides are generated by tidal raising forces associated with gravity and centrifugal forces and the earth’s orbiting system or position relative to the sun and moon. When these two bodies are in balance there are unbalanced forces on the surface of the earth that can push the ocean water left and right, causing tides. Tidal energy is taken from the kinetic energy of these orbiting forces to generate power. The orbits systems and tidal movements can be predictable years in advance and for this reason, it would be possible to estimate ahead when and how large the tides would be and the possible amount of electrical energy generated would be.
The offshores of Zanzibar lie in the belt with high M2 tides with 1-2-meter-high tidal amplitudes capable of generating a lot of power. Combined wind and tidal power could serve as a major Peaker, supplying offshore wind and tidal generated electricity during the peak hours. Evidence from the United States, United Kingdom and Canada suggests that an integrated energy system of this nature can be a game changer in addressing energy shortages, and driving the country towards a cleaner energy generation
What is required to make it happen?
- National Energy Policy and Strategy review and orientation towards offshore wind and tidal wave energy development. This would mean placing offshore wind and tidal wave power generation as part of the national energy systems power mix plan.
- Supporting institutional framework by breaking up TANESCO and ZESCO to curve out an independent agency responsible for offshore wind and tidal power. An agency similar to the US Bureau of Ocean Energy Management (BOEM) would be given a focused mandate to develop offshore wind and tidal wave power sector by mobilizing resources (technical and financial), attracting private sector investment and regulation, decreasing developer risks and encouraging inter-agency and stakeholder cooperation.
- Another policy direction would require the government to purchase at least given minimum amount of offshore wind and tidal wave capacity. The new agency would be tasked with delivery of such an amount to the National or Zanzibar power grid. This would provide a room for long-term off take Power Purchasing Agreements (PPA), decreasing major sources of uncertainty for project developers.
- Government to conduct necessary further research to support offshore and tidal wind projects. This would include update data collection to determine the costs benefit of offshore wind and electric systems configurations, site characterization, and dissemination would be required. Tanzania lacks marketable data.
- Political will and determination to explore new energy frontiers and commitments to a clean future. Although there could be some political sensitivities between the mainland and Zanzibar as towards having projects of this kind because the Union matters political configuration, the economic benefits from this potential outweigh the political undertones. To counterbalance, strategic project of this nature could be anchored under the current governments (Union and Zanzibar) blue economy development plans.