# Battery energy storage system (40 MWh) at Mtoni: design, supply, installation and initial operation, Zanzibar

- Status: Awarded. An official contract award has been published.
- Deadline: not recorded
- Buyer: Zanzibar Electricity Corporation
- Country: Tanzania
- Location: Mtoni, Unguja
- Reference: TZ-ZECO-380710-CW-RFB
- Notice type: Contract award
- Procedure: Request for Bids under the World Bank Procurement Regulations
- Contract model: Plant: design, supply and installation
- First published: 2025-01-31 on World Bank procurement notices (OP00465536)
- Official notice: https://projects.worldbank.org/en/projects-operations/procurement-detail/OP00465536
- Values: none published
- Financing: World Bank (IDA) IDA-68970
- Sectors: Renewables and storage
- Last checked against the official record: 2026-10-23
- Page: https://epcfeed.com/tenders/zanzibar-mtoni-40mwh-bess

## Scope

Design, supply, installation, testing, commissioning and initial operation of a 40 MWh battery energy storage system at Mtoni under the Zanzibar Energy Sector Transformation and Access Project. Contract duration 36 months.

## Contract award

- Winner: Sieyuan Electric Co., Ltd. (China)
- Signed price: USD 16,506,978.99
- Award notified: 2026-07-14
- Award published: 2026-08-28
- Duration: 36 months


| Bidder | Country | Evaluated price | Outcome |
| --- | --- | --- | --- |
| Sieyuan Electric Co., Ltd. | China | USD 12,421,500 | awarded |
| CCECC - XNEP | China | USD 12,256,546.65 | evaluated |
| HNAC Technology Company Limited | China | USD 12,462,119.58 | evaluated |
| Power China Guiyang Engineering Co. Ltd | China | USD 14,073,175.41 | evaluated |
| JV Eauxwel Nigeria Limited and Nidec ASI | Nigeria | USD 25,029,162.88 | evaluated |
| Zhongtian Energy Storage Technology Co., Ltd (ZTT) ZEST | China | USD 25,823,291.92 | evaluated |
| Tontan Project Technology Company Limited | Tanzania | not evaluated | rejected (Non responsive) |
| Novavis International | United States | not evaluated | rejected (Failure to meet minimum technical score) |
| Rimal Global Technical | Oman | not evaluated | rejected (Non responsive) |
| JV AIPEC and Spoweress Energy | China | not evaluated | rejected (Non responsive) |
| China Henan International Cooperation Group Co. Ltd (CHICO) | China | not evaluated | rejected (Non responsive) |
| Buckets Tanzania Limited | Tanzania | not evaluated | rejected (Non responsive) |
| Goldwind International Holdings | China | not evaluated | rejected (Failure to meet minimum technical score) |
| Dongfang Electric International Corporation - DEC | China | not evaluated | rejected (Non responsive) |
| JV SUMEC & CLOU | China | not evaluated | rejected (Non responsive) |
| Deltagen (Pty) Ltd | South Africa | not evaluated | rejected (Non responsive) |

## Official documents

- [Contract award notice (World Bank)](https://projects.worldbank.org/en/projects-operations/procurement-detail/OP00465536)
- [Invitation for bids (World Bank)](https://projects.worldbank.org/en/projects-operations/procurement-detail/OP00336539)

## Sources

1. [World Bank procurement notice OP00465536: Contract award, 40 MWh battery energy storage system at Mtoni](https://search.worldbank.org/api/v2/procnotices?format=json&id=OP00465536). Official notice, World Bank, Published 2026-08-28, Read 2026-10-23.
2. [World Bank procurement notice OP00336539: Invitation for Bids, battery energy storage system](https://search.worldbank.org/api/v2/procnotices?format=json&id=OP00336539). Official notice, World Bank, Published 2025-01-31, Read 2026-10-23.