Battery energy storage system (bess) services for rand water pumping operations – RFI

Rand Water is a Schedule 3B State Owned Entity (SOE) responsible for the abstraction,

treatment, and bulk supply of potable water to municipalities, industries, and mines across

Gauteng province mainly. The organisation operates one of the largest bulk water pumping

and distribution systems in the world, supplying water to an economic heartland that

accounts for a significant portion of South Africa’s gross domestic product.

The reliability and continuity of Rand Water’s pumping operations are therefore strategic to

national water security, economic stability, and public health. Rand Water’s pumping

infrastructure is highly energy-intensive, relying predominantly on large electrically driven

pump sets operating continuously to meet contractual demand obligations. These

operations are supplied through a combination of Eskom and Municipal electrical networks

and are subject to Time-of-Use (TOU) electricity tariffs, which impose significantly higher

operational costs.

Based on current measured data, Rand Water’s aggregated average electrical demand

across key pumping stations is approximately 271 MW, of which approximately 190 MW is

Eskom-supplied, and 81 MW is supplied through Municipal or alternative distributors. Major

energy-intensive stations include Zuikerbosch, Palmiet, Zwartkopjes, and Eikenhof, each

supporting critical bulk supply corridors within the Integrated Vaal River System.

In recent years, Rand Water has experienced increasing electricity cost escalation, driven

by:

• Rising Eskom tariffs under the Multi-Year Price Determination (MYPD) regime,

• Differential peak, standard, and off-peak tariff structures,

• Growing exposure to municipal electricity tariff variability, and

• Increasing emphasis on grid stability and demand management from electricity

suppliers.

Given the non-discretionary nature of water pumping, Rand Water has limited operational

flexibility to reduce or interrupt load during peak tariff windows without adversely affecting

water supply reliability. Consequently, Rand Water is pursuing technologies and system

architectures that enable energy cost optimisation without compromising pumping

continuity or hydraulic performance.

Battery Energy Storage Systems (BESS) have emerged globally as a mature and utility-

scale technology capable of:

• Shifting electrical energy consumption from peak to off-peak periods,

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• Reducing exposure to peak electricity tariffs,

• Improving power quality and voltage support,

• Enhancing operational resilience and energy system flexibility.

However, the application of BESS within large-scale, mission-critical water pumping

systems introduces specific technical, operational, and safety considerations. These

include:

• Seamless parallel operation with grid supply,

• Zero-interruption pumping under all battery states of charge,

• Integration with high-power motors and variable speed drives,

• Compliance with South African grid codes and utility protection philosophies,

• Long-term reliability over lifecycles extending 15–20 years.

Rand Water has therefore issued this Request for Information (RFI) to obtain detailed

technical, commercial, and operational input from the market on utility-grade Battery

Energy Storage System solutions suitable for integration into its bulk water pumping

infrastructure. The information received will be used to:

• Assess feasible BESS architectures and deployment strategies (centralised and/or

distributed),

• Inform preliminary system sizing and configuration options,

• Identify risks, constraints, and enabling requirements,

• Support the development of a subsequent Request for Proposal (RFP) and business

case.

This RFI is not a commitment to procure, but an information-gathering exercise designed

to ensure that any future procurement is technically sound, commercially prudent, and

aligned with Rand Water’s mandate to deliver secure, sustainable, and cost-effective bulk

water services.

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4. OVERVIEW OF THE REQUIREMENTS

4.1 Scope of Envisaged Packages/Main Activities

4.1.1 Envisage Package 1 – BESS for Shifting Demand from Peak to Off Peak

Package 1 envisages the design, supply, integration, and commissioning of a

grid-connected Battery Energy Storage System (BESS) configured primarily to

shift electrical energy demand from Eskom peak tariff periods to standard and

off-peak periods. The system shall operate in parallel with the existing electrical

supply and pumping infrastructure and be optimised to reduce Rand Water’s

exposure to high Time-of-Use (TOU) electricity tariffs associated with bulk water

pumping operations.

The BESS shall be engineered to discharge during defined peak tariff windows,

partially offsetting grid import to the pumping loads, and to charge during off-peak

and standard tariff periods without adversely impacting pump station operation,

motor performance, or power quality. Under no circumstances shall pumping be

interrupted or constrained due to battery charging, depletion of state-of-charge, or

system transitions. Seamless, automatic operation and fail-safe reversion to full

grid supply shall be inherent to the design.

This package shall include all associated power conversion equipment,

medium-voltage integration, automation, energy management systems (EMS),

protection, and balance-of-plant necessary to implement demand shifting in a

safe, reliable, and fully compliant manner. The proposed solution shall be scalable

and configurable to accommodate varying station demand profiles and shall be

capable of supporting long-term operation under Rand Water’s continuous

pumping duty cycle.

Important Note: Ideally Rand Water would prefer that the OEM provide this

system at their own capital cost, Rand Water would provide land, off-take and the

saving made from shifting load from peak to off-peak be shared.

4.1.2 Envisaged Package 2: BESS Providing Temporary Backup for Power Failures

Package 2 envisages the design, supply, integration, and commissioning of a

Battery Energy Storage System (BESS) configured to provide temporary electrical

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backup during grid power supply interruptions, including unplanned outages,

network disturbances, and short-duration voltage or frequency events affecting

Eskom or municipal supplies.

The primary function of this BESS package is to maintain uninterrupted pumping

operations for a defined autonomies period following a loss or degradation of grid

supply, until normal supply is restored or auxiliary generation systems (where

applicable) are fully available. The BESS shall operate in an online,

parallel-connected configuration, capable of instantaneous response to supply

failure without inducing pump trips, motor protection activation, or hydraulic

transients.

The system shall include high-speed detection, automatic islanding and

re-synchronisation capability, and seamless transition back to grid-connected

operation once stable supply is restored. The BESS shall be compatible with large

synchronous and induction motors, variable speed drives (VSDs), and existing

station protection schemes. Under normal conditions, the system shall remain in

a standby or partial-charge state to ensure immediate availability for backup duty.

This package shall include all associated power conversion systems,

medium-voltage protection, control and automation, Energy Management System

(EMS) logic, safety systems, and balance-of-plant required to provide a reliable

and compliant temporary backup solution. The design shall consider defined

backup durations, priority load selection, black-out ride-through requirements, and

integration with any existing standby generation, while meeting applicable grid

codes, safety standards, and Rand Water operational requirements.

4.2 Current Electrical Load Profile (Baseline Data)

Respondents shall base their proposed technical solutions, system architectures, and

preliminary sizing assumptions on the measured average electrical demand profile

across Rand Water’s pumping stations, expressed as Average Megawatts (MW) per

month. This demand profile represents the current baseline electrical loading

associated with continuous bulk water pumping operations and is provided to support

realistic modelling of Battery Energy Storage System (BESS) demand-shifting and

backup-operational scenarios.

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The demand profile includes pumping stations supplied directly by Eskom, as well as

stations supplied via municipal or alternative electricity distributors, as summarised

below.

Eskom-Supplied Stations

Station Average MW/month

Zuikerbosch 97.62 MW

Lethabo 9.89 MW

Zwartkopjes 27.25 MW

Palmiet 46.13 MW

BWD Pumping 9.59 MW

Total Eskom Supply 190.48 MW

Non-Eskom (Municipal) Supply

Station Average MW/month

Vereeniging – Emfuleni 26.89 MW

Eikenhof – City Power 35.90 MW

Mapleton – Ekurhuleni 13.05 MW

BWD Pumping – Emfuleni 1.87 MW

BWD Pumping – City Power 1.92 MW

BWD Pumping – Metsimaholo 1.28 MW

Total Other Supply 80.92 MW

The Grand Total Average Demand: 271.39 MW. These values provide an indicative

representation of Rand Water’s continuous electrical demand associated with bulk water

pumping operations and shall be used by respondents as the reference load profile for

evaluating BESS capacity, dispatch strategies, and system integration requirements.

Proposals may address station‐specific, regional, or portfolio‐wide BESS deployment

approaches, provided that the above demand data is clearly referenced and applied.

Important Note: The above electrical demand figures represent average monthly

consumption values and do not explicitly reflect instantaneous peak demand, transient

loading, or motor starting characteristics. Respondents are therefore required to clearly state,

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justify, and document all assumptions used in their modelling and design, particularly with

respect to:

• Peak‐to‐average load ratios

• Coincidence of electrical demand with Eskom Time‐of‐Use peak tariff windows

• Station simultaneity, operational diversity, and load aggregation factors

All such assumptions shall be explicitly identified in the RFI response and supported by sound

engineering rationale and applicable reference experience.

4.3 System Objective & Operational Philosophy

The primary objective of this initiative is the design and supply of a Battery Energy

Storage System (BESS) capable of partially or fully offsetting grid electricity

consumption during Time-of-Use peak tariff periods, while enabling effective load

shifting to standard and off-peak tariff periods. The BESS shall be engineered to

optimise Rand Water’s energy cost profile associated with bulk water pumping

operations, without negatively affecting operational performance, water delivery

obligations, or system reliability.

A mandatory operational constraint of the proposed system is that pumping operations

shall at no point be stopped, interrupted, or compromised because of battery charging

activities, full depletion of battery state-of-charge (including at 0% SOC), or any outage,

fault, or unavailability of the battery system. The BESS shall therefore be designed as

a parallel-operating system, interfacing continuously with the electrical grid and any

other available power sources, and shall incorporate fully automatic and seamless

transfer of electrical supply between sources.

The overall system architecture shall eliminate single points of failure and ensure that

no individual component failure, control transition, or protection event results in pump

tripping, inadvertent motor protection activation, or loss of hydraulic output. Continuous

pumping capability and stability of the water supply system shall take absolute

precedence over all energy management functions.

4.4 Bess Scope Of Supply

Respondents shall propose a fully engineered, utility-grade Battery Energy Storage

System (BESS) solution comprising all equipment, systems, and services required for

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safe, reliable, and continuous operation within Rand Water’s bulk water pumping

environment. The proposed solution shall be designed as an integrated system rather

than discrete components and shall be suitable for long-term operation under

continuous duty conditions typical of high-capacity pumping stations.

The Battery Energy Storage System shall consist of modular battery racks, containers,

or purpose-built buildings, arranged to allow scalability, redundancy, and

maintainability. Respondents shall propose appropriate battery chemistry options,

which may include lithium iron phosphate (LFP), nickel manganese cobalt (NMC),

sodium-ion, flow batteries, or equivalent proven technologies, together with clear

justification for suitability in terms of safety, lifecycle performance, and operating

conditions. The battery system shall include all necessary DC protection, isolation,

monitoring equipment, and a fully functional Battery Management System (BMS) to

ensure safe operation, fault detection, and effective life-cycle management.

The scope shall further include complete power conversion and electrical integration,

comprising grid-tied power conversion systems (PCS/inverters) suitably rated for the

intended duty, medium-voltage (MV) transformers, and MV switchgear with associated

protection systems. All cabling, busbars, earthing, and lightning protection systems

required for full integration shall be included. The BESS shall be synchronised with

existing MV busbars in a manner that ensures stable, parallel operation with the grid

and other power sources, while maintaining compliance with applicable grid codes and

protection philosophies.

An integrated automation, control, and energy management architecture shall be

provided. This shall include a robust Energy Management System (EMS) capable of

Time-of-Use (TOU)-based scheduling, peak shaving and load shifting, state-of-charge

management, and fail-safe and fallback logic to ensure continuous pumping under all

operating conditions. The system shall incorporate appropriate PLC and/or RTU

platforms, full SCADA integration with Rand Water’s existing control systems, and

facilities for secure remote monitoring and diagnostics.

The proposed solution shall also include all necessary balance-of-plant components,

including HVAC systems suitable for battery and power electronics environments, fire

detection and suppression systems compatible with the selected battery chemistry,

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and all related civil works, foundations, structural enclosures, and access

infrastructure. Comprehensive access control, safety, and occupational health systems

shall be incorporated to ensure safe operation, maintenance, and compliance with

statutory and Rand Water safety requirements.

4.5 Performance & Sizing Requirements

Respondents shall propose Battery Energy Storage System (BESS) sizing and

configuration solutions based on Rand Water’s aggregate electrical demand of 271.39

MW across all the stations, and/or on station‐specific or regional deployment options,

such as a Zuikerbosch‐focused installation or clustered regional pump station

solutions. Proposals may address centralised, distributed, or hybrid deployment

strategies, provided that the approach is clearly defined and justified in relation to

demand profiles, operational constraints, and economic performance.

Each proposal shall clearly specify the rated power capacity (MW/MVA) of the BESS,

the usable energy capacity (MWh), and the intended duration of discharge during peak

tariff windows. Respondents shall further indicate the percentage of the total station

load or aggregate system load that the BESS is designed to supply during Eskom peak

periods. All sizing assumptions, diversity factors, and load allocation methodologies

shall be explicitly stated and supported by sound engineering principles.

Respondents are encouraged to submit multiple configuration options to enable

comparative evaluation. These may include, but are not limited to, a cost‐optimised

option focused on partial peak shaving, a performance‐optimised option targeting deep

peak avoidance and maximum tariff offset, and alternative architectures comparing

distributed versus centralised BESS deployment across the Rand Water network.

Each option shall include a brief description of its operational philosophy, benefits, and

limitations.

For the purposes of modelling and system design, respondents shall assume Eskom

Time‐of‐Use tariff structures that include distinct morning and evening peak periods.

The BESS shall be configured to discharge during these peak tariff windows and to

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recharge during standard and off‐peak periods, in a manner that optimises energy cost

savings while preserving battery life and system availability. All proposed operating

strategies shall respect existing grid import limits, station electrical constraints, and

pumping operational requirements, and shall ensure continuous, uninterrupted

pumping at all times.

4.6 Reliability, Redundancy & Availability

The proposed Battery Energy Storage System (BESS) shall be designed to achieve a

minimum subsystem availability of not less than 98% on an annualised basis,

excluding scheduled maintenance. The system architecture shall prioritise operational

stability and shall ensure that transitions between operating modes, including charging,

discharging, standby, grid disturbances, or system faults, do not result in nuisance

tripping of pumps, motors, or variable speed drives (VSDs). All operating transitions

shall be seamless and fully coordinated with existing protection and control systems.

Where technically and economically justified, the design shall incorporate N+1

redundancy for critical components such as inverters, control systems, auxiliary power

supplies, cooling systems, and communications infrastructure. Respondents shall

clearly define the Mean Time to Repair (MTTR) for major system components and

describe maintenance strategies, spare‐parts philosophy, and service response

capabilities necessary to restore full system functionality within acceptable timeframes.

4.7 Power Quality & Grid Compliance

The BESS and all associated electrical equipment shall fully comply with the South

African Grid Code, Eskom interconnection requirements, and applicable NRS

standards, as well as any relevant municipal network codes where applicable. The

system shall be designed to operate within prescribed power quality limits, including

harmonic distortion limits in accordance with IEEE 519, applicable IEC 61000 series

standards, or approved local equivalents.

The BESS shall be capable of providing reactive power support and voltage regulation

at the point of connection to assist with network stability and power quality

management. Anti‐islanding protection shall be incorporated in accordance with utility

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requirements, and the system shall demonstrate appropriate dynamic voltage and

frequency ride‐through capability to prevent undesirable disconnections during grid

disturbances or transient e

vents.

4.8 Safety, Environmental & Cyber Security

The proposed solution shall be designed and implemented in accordance with

internationally recognised battery safety standards, including IEC 62619, IEC 62933,

and, where applicable, evidence derived from UL 9540A testing or equivalent

fire‐propagation assessments. Fire detection and suppression systems shall be

specifically designed to suit the selected battery chemistry and enclosure

configuration, with due consideration given to thermal runaway prevention,

containment, and safe access for emergency response.

All work shall comply with the requirements of the Occupational Health and Safety Act

and all applicable environmental legislation, standards, and Rand Water safety

procedures. In addition, the BESS control, communication, and monitoring systems

shall incorporate appropriate cybersecurity measures aligned with IEC 62443

principles, including secure access control, system hardening, network segmentation,

monitoring, and audit functionality to protect against unauthorised access and cyber

threats.

4.9 INFORMATION REQUIRED FROM RESPONDENTS

4.9.1 Technical Submissions

Respondents shall submit comprehensive technical information describing the

proposed system solution. This shall include system architectures, single‐line

diagrams, and detailed descriptions of the Energy Management System (EMS)

control philosophy, including Time‐of‐Use (TOU) optimisation logic. Performance

modelling shall be provided using the 271.39 MW aggregate Rand Water electrical

demand baseline, together with supporting assumptions relating to load

distribution, diversity, and duty cycles. Respondents shall also provide battery

degradation, efficiency, and lifecycle modelling, as well as a description of the

intended approach to protection coordination studies and grid impact

assessments.

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4.9.2 Commercial (ROM)

Respondents shall provide indicative, non‐binding Commercial information in the

form of Rough Order of Magnitude (ROM) estimates. This shall include preliminary

capital cost estimates, expected operations and maintenance costs, and projected

lifecycle costs. Indicative delivery, installation, and commissioning timelines shall

be stated, together with details of available warranty terms, performance

guarantees, and long‐term service and support offerings.

4.9.3 Experience & References

Respondents shall demonstrate relevant experience by providing details of at least

three (3) comparable utility‐scale BESS installations, preferably involving

high‐power industrial or critical‐infrastructure applications. Information on local

presence, technical support capabilities, and the ability to provide ongoing

operational and maintenance support within South Africa shall be included.

4.10 Key Emphasis for RFI Responses

In submitting RFI responses, respondents shall explicitly demonstrate how the

proposed BESS solution reduces Rand Water’s exposure to Eskom peak tariff

charges while ensuring that continuous pumping operations are preserved

under all conditions. Proposals shall further describe how the solution can be

scaled, replicated, or phased across Rand Water’s pump station portfolio, and

how technical, safety, and commercial risks are managed over the system

lifecycle. Respondents shall clearly indicate how the proposed solution remains

compliant, safe, and economically viable over an anticipated operating life of

15 to 20 years.

Rand Water further records that this RFI is not intended to restrict, limit or pre-

determine competition in any future procurement process. Information obtained

through this RFI will be used solely to inform internal planning, strategy

development, governance decision-making and the design of potential future

procurement processes.

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Any future concession, energy trading, wheeling, asset development or asset

transfer arrangement will be subject to detailed feasibility assessments, value-

for-money analysis, legal and regulatory due diligence, and approval by Rand

Water.

Respondents are advised that any future implementation involving electricity

generation, energy storage, demand-side management, trading, wheeling or

grid-connected services may require approvals, registrations or licences from

the National Energy Regulator of South Africa (NERSA), Eskom, municipal

distributors and/or other regulatory authorities.

Rand Water makes no representation regarding the availability, timing or

certainty of such approvals. Any future procurement or implementation will be

conditional upon the successful attainment of all required regulatory consents.

5. PROFESSIONAL REQUIREMENTS INDEMNITY

Respondents must confirm that they maintain in-force, claims-made Professional Indemnity

(PI) insurance appropriate to energy trading/advisory services, with adequate limits,

suitable territorial/jurisdictional scope, no exclusions for core trading advisory/settlement

support, an unlimited or appropriate retroactive date, and a minimum 24-month run-off after

expiry. A broker/insurer letter confirming current cover, limits, retro date, main exclusions

and deductible(s), together with a 5-year loss history declaration, should accompany RFI

submissions. Final requirements will be confirmed at RFP/award stage and may include

additional insurances (e.g., Public Liability, Cyber).

Rand Water reserves the right to verify the validity, scope and adequacy of all insurance

cover submitted and to require additional insurance cover at a later stage, should a formal

procurement process be initiated.

6. MINIMUM SUBMISSION REQUIREMENTS

In addition to the above the expert consultant is required to provide RAND WATER

with the following:

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• Respondents are requested to submit a comprehensive written response

to this Request for Information, addressing all sections and information

requirements outlined in the RFI.

• The response should be supported by relevant capability statements that

demonstrate the respondent’s experience, technical competence and

organisational capacity to provide energy trading services of a nature and

scale relevant to Rand Water.

• Respondents are encouraged to include illustrative non-confidential case

studies that highlight prior experience, operational approaches or

outcomes achieved for comparable clients, provided that such case

studies do not disclose commercially sensitive or client-identifying

information.

• In addition, respondents should complete and submit any compliance

checklists or questionnaires included as part of the RFI documentation, to

facilitate a consistent and efficient assessment of responses.

• Respondents must submit a signed declaration confirming the absence of

any actual, potential or perceived conflicts of interest in relation to this RFI

or any potential future engagement with Rand Water.

7. COST OF REQUEST FOR INFORMATION

Respondents are expected to fully acquaint themselves with the conditions,

requirements, and specifications of this RFI before submitting responses. Each

Respondent assumes all risks for resource commitment and expenses, direct or

indirect, of RFI preparation and participation throughout the RFI process. RAND

WATER is not responsible, directly, or indirectly, for any costs incurred by service

providers.

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8. TERMS AND CONDITIONS

Respondents shall sign a Non-Disclosure Agreement (NDA) with RAND WATER so that they

can have access to additional information for this RFI.

RAND WATER reserves the right to.

✓ Verify any information contained in a response.

✓ Postpone, withdraw, amend, modify, or cancel the RFI process at any time,

without prior notice and without liability to compensate or reimburse any person

pursuant to such.

8.1 Submission of RFI Responses

▪ To facilitate the preparation of the RFI Response, Respondents may access the

following website where the Document can be downloaded:

https://www.randwater.co.za/availabletenders.php/.

▪ The RFI Response, must be submitted to RAND WATER before or on closing date

and time at the following address: Tender Box (by the main entrance), 522 Impala

Road, Glenvista by not later than the time and date of 16:30 on 26 February 2026.

▪ RFI Responses reaching RAND WATER later than the cut-off time and date

specified above may, in the RAND WATER’s sole discretion, be rejected without

further consideration.

▪ RFI Responses may be submitted prior to the cut-off time and date specified

above, however only complete RFI Responses will receive attention from the

RAND WATER.

▪ All costs incurred by a Respondent in connection with this Document and the

preparation of its RFI Responses shall be borne by the Respondent.

▪ Responses submitted by companies must be signed by a person or persons duly

authorised thereto in a form of a resolution so passed by the appropriate governing

structure or letter of Delegation by an authorised Official of such Company.

8.2 Language of the RFI Response

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▪ The RFI Response and all documents forming part of it shall be in English.

▪ Any printed literature submitted with the RFI Response may be in another

language so long as it is accompanied by an English translation (made by an

accredited translator) of the entire document.

▪ All correspondence and any other documentation and oral communication

exchanged between the Respondent and the organisation shall be in English.

8.3 Further Information

▪ RAND WATER reserves the right to seek additional information from the

Respondent regarding its RFI Response, as it may, in its sole discretion,

determine, whether such information has been requested under this Document or

otherwise, and may require the Respondent to make oral presentations for

clarification purposes or to present supplementary information, in respect of its

RFI Response if so, required by the RAND WATER.

▪ The Respondent may, following the submission of a RFI Response, be requested

to engage with RAND WATER. Any meetings are likely to take place at RAND

WATER offices, which is at the following address: 522 Impala Road, Glenvista

2058, South Africa.

8.4 Contact with the Supply Chain Office

▪ All queries and requests for clarification in respect of this Document must be

addressed to the Supply Chain Office of Rand Water. E-mailed or oral requests

and queries addressed to persons other than a Supply Chain Official, at the

address, will not be entertained and will not receive a response. RAND WATER

will endeavour, in good faith, to respond to all reasonable written queries and

requests for clarification raised by the Respondent Rand Water will provide a final

response on clarifications by no later than ten (10) calendar days before the

closing date.

▪ The Respondent must give the name and contact details of the person whom it

appoints to undertake all contact with the SCM Office in its RFI Response.

▪ After the submission of its RFI Response, the Respondent may only communicate

with RAND WATER through such person and RAND WATER shall be entitled, at

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its sole discretion, to disregard any communication from the Respondent, that

does not come from such contact person, and that does not go directly to the

Supply Chain Office.

8.5 Compliance, Ethics and Market Conduct

▪ Respondents warrant that their submissions are prepared independently and

without collusion, consultation, coordination or agreement with any other

respondent. Any conduct that may constitute collusive behaviour, anti-competitive

practices or market manipulation may result in exclusion from future procurement

processes and referral to the appropriate regulatory authorities.

▪ Respondents must comply with all applicable legislation, including the Protection

of Personal Information Act (POPIA), and confirm that any information submitted

has been lawfully obtained and may be shared with Rand Water for the purposes

of this RFI.

▪ Respondents acknowledge that Rand Water is a responsible party under POPIA

and confirm that any personal information submitted is limited to what is necessary

for the purposes of this RFI, has been lawfully obtained, and may be processed,

stored and retained by Rand Water in accordance with its information governance

policies.

8.6 Competition Law and Fair Market Conduct

▪ Respondents must comply with the Competition Act, 1998 (as amended), and

warrant that their participation in this RFI does not involve any form of collusion,

bid-rigging, price-fixing, market allocation, or exchange of competitively sensitive

information with any actual or potential competitor.

▪ Rand Water reserves the right to disqualify any respondent and to report any

suspected anti-competitive conduct to the Competition Commission of South

Africa.

8.7 Intellectual Property and Use of Information

▪ All intellectual property rights in pre-existing proprietary methodologies,

technologies, software and designs submitted by respondents shall remain vested

in the respondent.

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▪ By submitting a response to this RFI, respondents grant Rand Water a royalty-

free, irrevocable, non-exclusive right to use, reproduce and analyse the

information contained in the submission for internal evaluation, planning,

governance and procurement development purposes.

▪ Rand Water shall not be restricted from developing its own specifications or

procuring similar solutions from third parties, provided that it does not unlawfully

disclose confidential proprietary information.

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ANNEXURE A: CHECKLIST

This checklist is provided for information-gathering purposes only and does not constitute

evaluation criteria, minimum eligibility requirements or scoring mechanisms for any future

procurement process.

A. GENERAL SUBMISSION INFORMATION

☐ Company name and legal entity

☐ Company registration number and country of registration

☐ Physical and postal address

☐ Primary contact person (name, designation, email, telephone)

☐ Local South African presence (office, partners, service capability)

☐ BBBEE status level (if applicable)

☐ Declaration of interest and conflict of interest statement

B. PROPOSED SOLUTION OVERVIEW

☐ Executive summary of proposed BESS solution

☐ Description of proposed system architecture (centralised, distributed, or hybrid)

☐ Stations or regions addressed (aggregate/system-wide or station-specific)

☐ Alignment with RFI Packages:

☐ Package 1 – Peak to Off‐Peak Demand Shifting

☐ Package 2 – Temporary Backup During Power Failure

☐ Key assumptions and exclusions clearly stated

C. TECHNICAL COMPLIANCE & DESIGN

C1. Battery Energy Storage System

☐ Battery technology and chemistry proposed

☐ Battery configuration (racks, containers, buildings)

☐ Battery Management System (BMS) description

☐ DC protection, isolation, and monitoring approach

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☐ Battery safety certifications (IEC 62619, IEC 62933, UL 9540A evidence)

C2. Power Conversion & Electrical Integration

☐ PCS/inverter ratings and configuration

☐ MV transformer specifications

☐ MV switchgear and protection philosophy

☐ Synchronisation approach with existing MV busbars

☐ Earthing, lightning protection, and cabling strategy

C3. Automation, Controls & EMS

☐ EMS control philosophy and operational modes

☐ TOU optimisation and scheduling logic

☐ Peak shaving and load shifting strategy

☐ SOC management and fail‐safe logic

☐ PLC/RTU architecture

☐ SCADA integration approach (protocols and signals)

☐ Remote monitoring and diagnostics capability

D. BESS SIZING & PERFORMANCE

☐ BESS sizing based on the 271.39 MW baseline clearly demonstrated

☐ Rated power capacity (MW and/or MVA) stated

☐ Usable energy capacity (MWh) stated

☐ Duration of peak‐period discharge defined

☐ Percentage of station/system load supplied during peak periods

☐ Multiple configuration options submitted (if applicable):

☐ Cost‐optimised option

☐ Performance‐optimised option

☐ Distributed vs centralised option

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Form No: RW SCM 00073 F REQUEST FOR INFORMATION

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☐ Justification of peak‐to‐average assumptions

☐ Coincidence and diversity factors stated

E. RELIABILITY, AVAILABILITY & REDUNDANCY

☐ Availability target ≥98% stated

☐ Redundancy philosophy (N+1 or equivalent) defined

☐ No‐trip, bumpless transition strategy described

☐ Mean Time to Repair (MTTR) defined

☐ Maintenance philosophy and spare‐parts strategy

F. POWER QUALITY & GRID COMPLIANCE

☐ Compliance with South African Grid Code confirmed

☐ Compliance with Eskom and relevant municipal requirements confirmed

☐ Harmonic distortion compliance (IEEE 519 / IEC) demonstrated

☐ Reactive power and voltage support capability stated

☐ Anti‐islanding protection described

☐ Voltage and frequency ride‐through capability described

G. SAFETY, ENVIRONMENTAL & CYBER SECURITY

☐ Fire detection and suppression system design provided

☐ Environmental and thermal management strategy provided

☐ OHSA compliance confirmation

☐ Cybersecurity approach aligned with IEC 62443 principles

☐ Secure access, monitoring, and audit functionality

H. PERFORMANCE MODELLING & STUDIES

☐ Load and energy modelling provided

☐ TOU optimisation modelling results included

☐ Battery degradation and lifecycle performance modelling (15–20 years)

☐ Round‐trip efficiency stated

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Form No: RW SCM 00073 F REQUEST FOR INFORMATION

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☐ Grid impact and protection study approach outlined

I. COMMERCIAL INFORMATION (ROM)

☐ Capital cost estimate (ROM)

☐ Operations and maintenance cost estimate

☐ Lifecycle cost assumptions

☐ Delivery, installation, and commissioning timeline

☐ Warranty terms (equipment and performance)

☐ Long‐term service and support offerings

J. EXPERIENCE & REFERENCES

☐ At least three (3) comparable utility‐scale BESS references provided

☐ Reference project size, application, and year of commissioning stated

☐ Client contact details provided

☐ Local execution and support capability demonstrated

K. RISK & ASSUMPTIONS

☐ Key technical risks identified

☐ Mitigation strategies described

☐ Commercial and programme risks identified

☐ Clear listing of assumptions and exclusions

L. DECLARATION

☐ Confirmation that the submission is non‐binding

☐ Acknowledgement that this is an RFI and not a commitment to procure

☐ Authorised signatory and date

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No specific requirements found