Grid forming technologies – RFI for professional services (national)

The RFI is open to all manufacturers or suppliers to provide NTCSA with information on grid forming technologies, as NTCSA is introducing these into its network. NTCSA is gathering information from OEM providers of grid-forming technology, particularly when paired with a BESS.

The RFI is open to all manufacturers and suppliers of grid-forming (GFM) technologies, particularly GFM paired with battery energy storage systems (BESS). NTCSA seeks information on the following capabilities:

• Ability to set its own voltage and angle, supporting networks with high renewable energy penetration.
• Provision of system strength, which inverter-based resources typically consume.
• Provision of inertial response and very fast active power injection to aid frequency stability.
• Damping of oscillations to mitigate potential instability.
• Black start capability and island mode operation without synchronisation to the network.
• Stabilising voltage.
• Active power control over a wide range of voltage deviations, avoiding disconnection during disturbances.
• Phase jump mitigation.

Respondents should provide as much supporting information as possible. Broad participation from grid-scale providers is encouraged to avoid polarising specifications.

Respondents should answer the queries listed and provide as much supporting information as possible. Broad response from grid-scale providers is encouraged to form a clear picture of general capabilities and avoid polarising specifications.

GFM BESS contributes to system inertia and frequency stability, damps oscillations, provides black start capability and island mode operation, stabilises voltage, maintains active power control during voltage deviations, and mitigates phase jumps.

Mandatory returnable: the E-Tendering Training Acknowledgement Form must be fully completed, signed, and submitted to NTCSA within the prescribed period. Failure to do so renders the bidder non-responsive and disqualified.

• The form requires the enquiry number, business name/JV, contact person, landline, cellphone, and email address.
• The bidder must acknowledge having completed self-training via the e-Tendering Noddy Guide, video, or clarification meeting, and confirm ability to operate the E-Tendering Solution.
• The form must be signed by an authorised signatory, with designation and date.

The E-Tendering Training Acknowledgement Form is a mandatory returnable document. It must be fully completed and submitted to NTCSA within the prescribed period. Failure to do so will render the tenderer non-responsive and disqualified from the procurement process.

Submission of the fully completed and signed E-Tendering Training Acknowledgement Form is mandatory. Failure to submit the form within the prescribed period will render the tenderer non-responsive and disqualified from the procurement process.

The tender is a Request for Information (RFI) for Grid Forming Technologies, issued by Eskom National Transmission Company of South Africa (NTCSA). The specific scope is not detailed in this document; it is set out in the Tender Data and the specification/works information.

Closing date: 13 November 2026 at 10:00 (SAST).

• Compulsory site visit and/or clarification meeting: details (date, time, venue) are stated in the Tender Data. Attendance is compulsory; failure to attend results in disqualification.
• Tender opening: at the time and place stated in the Tender Data, in the presence of tenderers' representatives who choose to attend.

A site visit and/or clarification meeting is stipulated as compulsory. Details (date, time, venue) are in the Tender Data. Failure to attend results in disqualification. Tenderers may ask questions for clarity during the meeting.

Enquiries and clarifications:

• All requests for clarification must be addressed in writing to the NTCSA Representative identified in the enquiry document. No queries may be addressed to any other NTCSA official.
• NTCSA will publish all requests for clarification and responses (without divulging the tenderer's name) on the platform/s on which the tender was advertised.
• It is the tenderer's responsibility to check the NTCSA Tender Bulletin and NT e-Tender Portal regularly for clarifications, addenda and any changes to the closing date and time.
• Submission address: as stated in the Tender Data (the address at which tenders must be submitted, with the designated tender box).

Submission method: paper only, at the address and tender box stated in the Tender Data. Facsimile or email accepted only if the Tender Data says so.

• Submit one complete original tender in paper form plus one complete paper copy, each in a separate package marked "ORIGINAL" and "COPY". If an electronic copy is requested, package it separately and mark it "ELECTRONIC COPY".
• Seal the separate packages together in an outer package marked "Confidential". On the outside of each package and the outer package state: the NTCSA submission address, the Invitation to Tender number, the tenderer's name, physical address, email address and the contact telephone number of the authorised representative.
• Tenders must be in English, completed in ink (not pencil), and signed by a person duly authorised to bind the tenderer.
• Tenders must be received by the closing date and time. Late tenders are returned unopened; proof of posting or courier delivery is not proof of delivery. NTCSA is not responsible for misplacement or premature opening if packaging is incorrect.
• The closing time is South African Standard Time (SAST, GMT+2), determined by the Telkom time signal, and is strictly adhered to.
• Do not alter or add to tender documents except to correct errors or comply with NTCSA instructions; initial all alterations. Do not use correction fluid or tape.
• Alternative tenders are allowed only if a main tender is also submitted and the Enquiry permits alternatives, based only on criteria in the Tender Data.
• Returnable documents (all must be completed and submitted by the closing deadline):
• Acknowledgement Form: confirms receipt of the enquiry documents and states whether the tender is for the whole or part of the works/services/supply.
• SBD 1 (Invitation to Bid): bidder and contact details, signed as the offer cover page.
• SBD 4 (Declaration of Interest): discloses whether any director or shareholder is employed by the state or connected to anyone at the procuring institution.
• SBD 6.1 (Preference Points Claim): claims B-BBEE points under the PPPFA 80/20 or 90/10 system.
• SBD 8 (Declaration of Bidder's Past Supply Chain Management Practices).
• SBD 9 (Certificate of Independent Bid Determination): certifies no collusion and no price disclosure.
• Authority to Sign / Board Resolution: authorises the named signatory to bind the bidder.
• Where an agent submits on behalf of a principal, an authenticated copy of the authority to act as agent.
• Any other mandatory returnables stated in the Tender Data.
• Mandatory returnables required at closing will not be requested or accepted after the closing date and time.
• Disqualification risks: missing or unsigned returnables; failure to submit both original and copy in paper form; late submission; incorrect packaging; unauthorised alterations; failure to attend a compulsory site visit or clarification meeting.

Evaluation stages:

1. Basic compliance: NTCSA determines before detailed evaluation whether each tender meets the basic compliance requirements in the Enquiry. Failure renders the tender non-responsive.
2. Mandatory returnables: a tender missing mandatory documents or information by the required deadlines is disqualified.
3. Designated materials: failure to meet stipulated requirements for designated materials results in disqualification.
4. Functionality (if a criterion): tenderers are scored against functionality criteria and must meet the minimum threshold stated in the Tender Data to proceed.
5. Financial analysis (if applicable): NTCSA assesses the financial risk of doing business with the tenderer. If mitigating factors are insufficient or the risk is too high, the tenderer is not considered for award.
6. Price evaluation: Price is evaluated per the Tender Data, considering factors such as CPA, FOREX, commodity increases, discounts, NPV and forecasted rates of invoicing.
7. Specific Goals (B-BBEE): scored with reference to supporting documentation. Failure to meet Specific Goals or submit proof by closing results in zero points for Specific Goals within the 90/10 or 80/20 allocation, but not disqualification if otherwise acceptable.
8. Ranking: NTCSA adds the score for Pricing and Specific Goals and ranks tenderers from highest to lowest.

• Preference point system: 90/10 or 80/20 as stated in the Tender Data.
• Arithmetical errors: if there is a discrepancy between figures and words, the words prevail. NTCSA checks the highest-ranked tender for decimal misplacement, omissions and arithmetical errors, and notifies the tenderer to confirm or accept corrections. If the tenderer does not correct or accept, the tender is rejected.
• Objective criteria: a contract may be awarded to a tenderer that did not score the highest points only in accordance with Section 2(1)(f) of the PPPFA, with Objective Criteria stipulated in the Enquiry. Functionality and any element of the B-BBEE scorecard may not be used as Objective Criteria.
• Reverse e-auction: may be used, utilising the 90/10 and 80/20 Price and Preference point systems. Where used, tenderers must submit a complete tender without prices; any included prices will not be considered.
• Grounds for rejection: proof of influencing the process, collusion, bid rigging, or fraudulent activity in connection with the enquiry.
• Misrepresentation or falsification of any information, certificate, affidavit or document may lead to disqualification; fraud related to B-BBEE certificates or fronting is reported to the B-BBEE Commission.

The tender is a Request for Information (RFI) for Grid Forming Technologies, issued by Eskom National Transmission Company of South Africa (NTCSA).

• The specific scope, deliverables, quantities, locations and technical requirements are not stated in this document; they are set out in the Tender Data and the specification/works information.
• The Acknowledgement Form must state whether the tender is for the whole or part of the works, services or supply identified in the specification and/or works information.

Tenderers must provide proof, to NTCSA's satisfaction, that safety, health, environmental and quality (SHEQ) systems, policies and capabilities are in place by the deadline stipulated in the Enquiry. All SHEQ costs and personnel must be reflected in the tender. The tenderer must comply with NTCSA's SHEQ requirements and any other applicable legislation.

Rates and prices must include all duties, taxes (including VAT) and levies applicable 14 days prior to closing. Prices must be fixed for the contract duration unless otherwise provided. Prices must be stated in South African Rand unless instructed otherwise, with exchange rate and base date as stipulated. The Pricing Schedule must include a line item for cataloguing if required. Arithmetical errors are corrected per the rules in the main financialRequirements section.

Pricing format:

• Rates and prices must include all duties, taxes (including VAT) and other levies payable by the tenderer if successful, applicable 14 days prior to the closing date and time.
• Rates and prices must be fixed for the duration of the contract and not subject to contract price adjustment except as provided in the Enquiry.
• Prices must be stated in South African Rand unless instructed otherwise, in accordance with the exchange rate and base date stipulated in the Invitation to Tender.
• The Pricing Schedule must include a line item for cataloguing if cataloguing is a requirement; NTCSA will pay for cataloguing.
• Arithmetical errors: the amount in words prevails over figures. NTCSA checks the highest-ranked tender for decimal misplacement, omissions and arithmetical errors, and may correct them; the corrected total is binding.
• Bid security / performance security: if a performance bond or demand guarantee is required, the tenderer must select at least two financial institutions from the NTCSA-approved list.
• Insurance: NTCSA's insurance (if any) may not be full cover; the tenderer should seek qualified advice.
• Financial capacity: NTCSA assesses the financial risk of doing business with the tenderer; if the risk is too high and no sufficient mitigating factors exist, the tenderer will not be considered for award.

Eligibility:

• Must comply with the eligibility criteria stated in the Tender Data and must not be under any restriction to do business with NTCSA or State-Owned Companies.
• CIDB: where stipulated in the Tender Data, tenderers must be registered with the Construction Industry Development Board at closing, or be capable of being registered within 21 working days from the closing date and time.
• B-BBEE: a valid B-BBEE certificate or affidavit is required to claim preference points; fraud or fronting is reported to the B-BBEE Commission.
• SHEQ: tenderers must provide proof, to NTCSA's satisfaction, that safety, health, environmental and quality (SHEQ) systems, policies and capabilities are in place by the deadline stipulated in the Enquiry. All SHEQ costs and personnel must be reflected in the tender.
• Legislation: comply with relevant legislation and regulatory instruments, including National Treasury Instruction Notes, CIDB Regulations (for construction works), materials designated for local content by the dtic, PPPFA Regulations, Amended B-BBEE Codes, COIDA, OHS Act, and NTCSA's SHEQ requirements.
• Contract Skills Development Goals (CSDG): if awarded a contract, the Contractor must achieve the CSDG per the CIDB Standard for Developing Skills through Infrastructure Contracts. Applicable to contracts of R5 million or more (professional/service contracts) or CIDB grade 7 or higher (engineering/construction works), with duration of 12 months or more.
• Contract Participation Goals (CPG): the Contractor must achieve CPG for engaging targeted enterprises per the CIDB standard. Applies to construction works contracts in GB and CE classes, with minimum duration of 6 months, and where at least 25% of the main contract is expected to be subcontracted in specified CIDB classes (CE, EB, GB, ME).
• Designated materials: failure to meet stipulated requirements for designated materials results in disqualification.

Tenderers must provide proof of safety, health, environmental and quality (SHEQ) systems, policies and capabilities to NTCSA's satisfaction by the stipulated deadline. All SHEQ costs and personnel must be reflected in the tender. Compliance with COIDA, OHS Act and NTCSA's SHEQ requirements is mandatory.

NTCSA may accept or reject any variation, deviation or alternative tender, and may accept the whole or any part of the tender. NTCSA may cancel the tender at any time before contract conclusion, with written reasons upon request. NTCSA and its related parties are not liable for any losses, claims or damages arising from participation in the tender process. NTCSA reserves the right to enter into mandated negotiations with selected tenderers.

• Tender validity: the tender must remain valid for acceptance within the validity period stated in the Tender Data. If NTCSA requests an extension, the tenderer may agree (without modifying the tender) or be excluded from further consideration. If validity expires before contracts are concluded, the process is deemed concluded without an award.
• Confidentiality: all matters arising in connection with the procurement are confidential; use NTCSA documents only for preparing the tender.
• Insurance: NTCSA's insurance (if any) may not be full cover; the tenderer should seek qualified advice.
• Performance security: if a performance bond or demand guarantee is required, the tenderer must select at least two financial institutions from the NTCSA-approved list.
• Contract formation: NTCSA will revise contract documents to account for addenda, returnables, and agreed changes; both parties' authorised signatories will sign the original and one copy of the Form of Agreement.

Special conditions include: compulsory site visit/clarification meeting (failure to attend disqualifies); packaging and marking requirements for submission; no alterations to documents except with initialling; no correction fluid/tape; alternative tenders only with a main tender and only if permitted; mandatory returnables must be submitted by closing; late tenders returned unopened; NTCSA may issue addenda and grant extensions; the successful tenderer may be required to provide cataloguing information and label materials per NTCSA specifications.

Evaluation follows the stages described in the main evaluationCriteria section: basic compliance, mandatory returnables, designated materials, functionality (if applicable), financial analysis, price evaluation, Specific Goals scoring, and ranking. Specific Goals are scored within the 90/10 or 80/20 allocation; failure to meet them results in zero points but not disqualification if otherwise acceptable. Objective criteria under PPPFA Section 2(1)(f) may apply, but functionality and B-BBEE elements cannot be used as objective criteria. Reverse e-auction may be used, in which case tenders must be submitted without prices.

NTCSA invites suppliers to submit information on Grid Forming Technologies. The RFI is a market-sounding exercise to gather technical details on GFM BESS capabilities.

Closing date: 13 November 2026 at 10:00 AM (South African Standard Time).

No briefing or site visit is mentioned.

Contact: Claire Sennelo

Role: Assistant Officer, Procurement

Email: [email protected]

Telephone: 011 800 8111

Submission method: electronic only via the NTCSA E-Tendering page (Tender bulletin site).

• No physical or hard-copy submissions accepted.
• All documents must be in PDF and Excel format.
• File size limit: 50MB per file; total submission limit: 900MB.
• No zip or compressed files allowed.
• If resubmitting, only the latest version is accepted; earlier submissions become null and void.
• Submission status must be marked as complete.
• Supplier Help Manual and video are available on the NTCSA E-Tendering page.
• It is the supplier's responsibility to ensure the submission is uploaded before the closing date and time.

This is a Request for Information (RFI), not a formal bid. No scoring or evaluation criteria are stated. Suppliers must respond to the technical questions in the response sheet. There is no stated minimum qualifying score or preference point system.

The RFI seeks information on Grid Forming Technologies (GFM BESS) for NTCSA. Suppliers must answer a detailed response sheet covering:

• Definition of GFM BESS and the technical standard referenced.
• Track record: GW/GWh of GFM BESS supplied specifically for GFM capabilities, list of power utilities and quantities of direct GFM orders, and duration of supplying GFM technologies.
• Capability to form its own voltage and angle, with test documentation and conformance to internationally recognised codes and standards.
• System strength provision: tests, conditions (e.g. SCR, voltage ranges, temperature, altitude), capability curves, fault current levels, and oversizing/cost implications.
• Inertial response: technical description, tests, standards, capability curves, and impact on battery lifetime.
• Oscillation damping: frequency bands, damping ratios, tests, and interaction with other GFM sources.
• Black start: capability, size/storage capacity typically installed, tests, standards, oversizing, and ability to provide auxiliary power to a tripped coal generator (including managing inrush currents).
• Island mode: capability, tests, standards, island size range, transitions between grid-connected and islanded operation.
• Voltage control: capability, tests, standards, reactive power levels, oversizing, and capability curves.
• Fault ride-through (LVRT/HVRT): compliance with envelopes, reactive current injection, active power recovery, and field test results.
• Phase jump withstand: maximum phase angle change, tests, standards, and capability curves.
• Provision of models: static and dynamic models (e.g. PSSE, PowerFactory, RSCAD, PSCAD), willingness to provide controller modules for software/hardware-in-the-loop testing, and support for jurisdiction-style validation tests.

The RFI response sheet contains questions for suppliers to answer regarding their Grid Forming (GFM) BESS technology, covering: definition and technical standards, track record and experience, voltage and angle forming capability, system strength provision, inertial response, oscillation damping, black start capability, island mode operation, voltage control, fault ride-through, phase jump withstand, and provision of models for simulation and testing.

Suppliers must describe how the controller avoids adverse interactions or loss of synchronism when multiple GFM units experience phase jumps or rapid angle changes in the wider system.

Suppliers must be willing to provide controller modules for software-in-the-loop and hardware-in-the-loop testing when required. Static and dynamic models must be provided in a template agreed with the System Operator or Network Service Provider (e.g. PSSE, PowerFactory, RSCAD, PSCAD).

No pricing schedule is included. The RFI does not request pricing information.

No pricing or financial requirements are stated. The document is an RFI and does not request pricing information.

No specific compliance requirements are stated (e.g. CSD, tax clearance, B-BBEE, CIDB). Suppliers must provide company registration number and contact details in the response sheet.

No health and safety requirements are stated. The RFI focuses on technical capabilities, including black start provision for a tripped coal generator, but does not specify OHS obligations.

No contractual terms are stated. The document is an RFI and does not include contract conditions, duration, termination, or penalties.

RFI submissions must be uploaded via the NTCSA Tender bulletin site on the NTCSA E-Tendering page. All documents must be in PDF and Excel format (50MB per file, 900MB total). No zip/condense files or hard copies accepted. If resubmitting, the latest version will be accepted and previous submissions null and void. Submission status must be indicated as complete. Supplier Help Manual and video available on NTCSA E-Tendering page.