The Eswatini Electricity Company (EEC) has issued a Request for Expressions of Interest (REOI) for consultancy services to undertake a feasibility study for the proposed Ngwempisi Multipurpose Hydro Scheme. The assignment is being undertaken under the World Bank-financed ASCENT-Eswatini Project.
The REOI was published on 10 August 2026, with EEC seeking to shortlist consulting firms for the subsequent procurement of the feasibility study consultancy.
A multipurpose water and hydropower development
The proposed project concerns development of the Ngwempisi River as a multipurpose water resource. In addition to hydropower generation, the feasibility study will consider water supply, irrigation and environmental-flow requirements.
The current EoI does not specify an installed capacity for the proposed hydropower scheme. Earlier studies, however, have consistently identified a potential development of around 120 MW. Eswatini's Energy Masterplan 2034 refers to a pre-feasibility study which identified potential of approximately 120–140 MW, while also referring specifically to an AfDB-supported pre-feasibility study for a 120 MW Ngwempisi Hydro Scheme.
The World Small Hydropower Development Report similarly described the Ngwempisi cascading scheme as having an expected total installed capacity of 120 MW across three sites. More recently, the World Bank has referred to the proposed 120 MW Ngwempisi hydro project as a potential peaking power plant.
The new feasibility study will review and update the earlier work, so the final configuration and capacity should not be regarded as confirmed at this stage.
The project builds on a 2018 pre-feasibility study of the Ngwempisi Hydropower Cascading Scheme. The appointed consultant will review that earlier study, identify gaps and update its assumptions, including the assessment of alternative dam configurations, scheme options and storage capacity.
The study is intended to develop preliminary designs capable of meeting projected needs through 2050, while optimising infrastructure for water supply, hydropower and irrigation and taking account of environmental flows, socio-environmental constraints and international transboundary agreements.
Scope of the consultancy
The required services cover a broad range of technical, environmental, economic and institutional disciplines. Key tasks include:
- reviewing existing reports, data and policies relating to the Ngwempisi River and the surrounding region;
- reviewing and updating the 2018 pre-feasibility study;
- assessing water-resource availability, future water demand and the potential impacts of climate change;
- evaluating storage structures and consumptive water uses;
- assessing the downstream irrigation potential, including land and soil suitability, farming systems, value chains, cropping systems and future irrigation-water demand;
- undertaking a preliminary Environmental and Social Impact Assessment (ESIA) and preparing a preliminary Environmental and Social Management Plan;
- preparing preliminary scheme layouts, cost estimates and economic and financial analyses;
- assessing potential financing arrangements, including government financing, multilateral development-bank loans and public-private partnerships; and
- preparing high-level preliminary designs balancing water supply, hydropower, irrigation and environmental-flow requirements.
The assignment therefore calls for a multidisciplinary consulting team with experience extending well beyond hydropower engineering alone.
Experience requirements
Consultants must demonstrate at least 10 years of experience in consultancy assignments of a similar nature and complexity. The EoI also requires evidence of at least two relevant assignments covering areas such as water-resource planning, hydropower, multipurpose dam development, irrigation, environmental and social assessment, feasibility or pre-feasibility studies, economic analysis or related infrastructure advisory services.
In addition, firms must demonstrate:
- at least one relevant assignment in Africa;
- at least one assignment specifically involving hydropower development;
- at least one multidisciplinary infrastructure study covering technical, environmental, social, economic, financial and institutional aspects.
Consultants may form joint ventures or consortia to combine their qualifications and experience.
EEC intends to shortlist no more than eight consulting firms, which will subsequently be invited to submit technical and financial proposals. The final consultant will be selected using the Quality and Cost Based Selection (QCBS) method.
Deadline for Expressions of Interest
Expressions of Interest must be submitted no later than 11:00 SAST on 1 September 2026.
Download the Request for Expression of Interest from the Eswatini Electricity Company