Call for Tender—-Installation of an 11.5kW Solar Energy System for the Integrated Energy Centre (IEC)

Job Description

 

Call for Tender  

Installation of an 11.5kW Solar Energy System for the Integrated Energy Centre (IEC) in Fogbo,  Western Area Rural District . 

About TENN: 

The Energy Nexus Network (TENN) is a regional knowledge and facilitation hub for scaling  decentralized renewable energy solutions using sustainable energy (SDG7) as a critical catalyst and entry  point to improve major development outcomes. 

TENN’s mission is to build resilient ecosystems around decentralized renewable energy. As an  aggregator, TENN enables cross-sectoral dialogue and facilitates business, policy, and technical  engagements to strengthen linkages between energy and key sectors such as livelihood, health, climate  action, and agri-value chains. 

TENN provides advisory support to enhance the institutional capacities of energy sector agencies and  local institutions to address energy priorities coherently. The organization focuses on the Energy Healthcare Nexus and Energy-Livelihood Nexus to improve social and development outcomes. 

Scope of Operations: 

∙ Collaborates with local and international partners to develop and strengthen sustainable  ecosystems for decentralized renewable energy access in underserved communities. ∙ Serves as the regional energy ecosystem hub for innovating and scaling sustainable decentralized  renewable energy solutions through the Global SDG7 Hubs an initiative of the SELCO  Foundation  

∙ Champions initiatives that integrate productive use applications of energy to support  development, focusing on enterprises, innovators, sectoral champions, and policymakers. ∙ Conducts needs assessments, pilot projects, and solution deployment in agri-value chains,  healthcare, and livelihoods, particularly benefiting women and small businesses in remote areas.  

Background: 

The Energy Nexus Network (TENN), in partnership with GOAL Sierra Leone funded by Jersey Overseas  Aid (JOA), is implementing the project “Resilience of the Blue Economy: Enhanced Resilience of  Rural Communities Through Women-Led Conservation, Financial Inclusion, and Livelihood  Diversification.” Under this initiative, TENN seeks proposals from qualified building construction  companies for the construction of one (1) eco-friendly Integrated Energy Centre (IEC)  superstructure at Forgbo, Western Rural District. The IEC will house productive use appliances  powered by rooftop-mounted solar PV installations, providing a hub for resilient micro-businesses.

Scope of Work: 

The selected EPC company will be responsible for: 

∙ Designing a complete 11.5kW solar PV system tailored to the IEC’s load requirements. ∙ Supplying high-quality, durable, and certified components (solar panels, hybrid inverter,  batteries, mounting structures, etc.). 

∙ Installing rooftop-mounted PV panels on the IEC building. 

∙ Wiring, testing, and commissioning of the full system (inclusive of AC/DC components). ∙ Training local operators and handing over a comprehensive operation & maintenance (O&M)  manual. 

∙ Providing one-year post-installation technical support and defect liability warranty. System Requirements: 

∙ Solar PV Capacity: 11.5kW 

∙ Battery Bank: Appropriately sized for at least 2 days of autonomy 

∙ Inverter: Hybrid inverter with remote monitoring capability 

∙ Mounting: Roof-mounted structure (provided by contractor) 

∙ Usage: To power productive-use equipment within the IEC 

∙ Compliance: Must meet IEC and national energy standards 

Timeline: 

∙ Publishing Date: 5th June, 2025 

∙ Deadline for Submissions of bids: 26th June, 2025 

∙ Bid Opening Date: 2nd July, 2025 

∙ Contract Award Date: 11th July 2025 

∙ Project Completion Timeline: Within 7 days of contract signing 

Point of Contact: For all technical inquiries, please contact: +23233820964/+23278421242 Closing Date for Inquiries: 12th June, 2025 

Method of Submission: 

All interested Energy Procurement Construction (EPC) Company firms are requested to submit a  complete proposal package including technical and financial bids via: 

Hard Copy Submission: 

JOA Procurement Committee 

The Energy Nexus Network (TENN) 

30 FAO Drive, Aberdeen 

Freetown, Sierra Leone 

Soft Copy Submission (PDF format):

Email to: tennprocurement.joa@gmail.com 

Evaluation Criteria: 

Essential Criteria: 

∙ Company registration and legal documentation 

∙ Evidence of similar project experience in Sierra Leone or region (at least 3 projects from 2022– 2025) 

∙ Site visit evidence (photos, videos, and signed site visit form) 

Award Criteria: 

1. Quality – 60% 
2. Technical Soundness of Proposed Design 

∙ Provide a clear, technically justified system design, including load analysis and sizing. ∙ Criteria for evaluation: Alignment with energy needs, design efficiency, and clarity of system  architecture. 

1. Component Specifications and Warranties 

∙ Submit datasheets and warranty details for all major components: 

o Solar panels: Minimum 20-year warranty 

o Lithium batteries: Minimum 2-year warranty 

o Hybrid inverters: Minimum 2-year warranty 

o Breakers, and accessories: Minimum 1-year warranty 

∙ Criteria for evaluation: Compliance with minimum warranty periods, product certifications,  and technical specifications. 

1. Demonstrated Experience with Off-grid/Mini-grid Installations 

∙ Provide evidence of at least 3 similar completed projects (e.g., completion certificates, client  references, site photos). 

∙ Criteria for evaluation: Relevant experience, documented proof of past work, and successful  implementation track record. 

1. Environmental Safety and Quality Control Plan 

∙ Submit a clear plan for environmental safety and quality assurance, including environemntal management and safety protocols. 

∙ Criteria for evaluation: Adherence to environmental standards and robustness of quality control  measures.

1. Local Training and Operation & Maintenance (O&M) Capacity 

∙ Provide a sustainability plan for O&M services, including: 

o Local technician training schedule 

o Duration and frequency of O&M checks 

o End-user training manuals and posters on do’s and don’ts 

∙ Criteria for evaluation: Strength and clarity of the sustainability plan, training tools, and  commitment to post-installation support. 

2. Price – 30% 
3. Competitive and Transparent Cost Breakdown 

∙ Submit a comprehensive, itemized BoQ showing all cost elements. 

∙ Criteria for evaluation: Transparency, competitiveness, and completeness of cost structure. b. Value for Money and Warranty Terms 

∙ Justify pricing with quality components, strong warranties, and reliable post-sale support. ∙ Criteria for evaluation: Overall value proposition, compliance with warranty standards, and  cost-efficiency. 

3. Delivery – 10% 
4. Realistic and Detailed Work Plan 

∙ Submit a Gantt chart or project timeline with implementation milestones within 7 calendar days. ∙ Criteria for evaluation: Realism, efficiency, and scheduling accuracy. 

1. BoM, BoQ, and Timeline Alignment 

∙ Ensure all documents are consistent and aligned with the proposed timeline. ∙ Criteria for evaluation: Completeness and accuracy of deliverables. 

1. Technical Installation Diagram 

∙ Submit a single-line or flow diagram showing all component interconnections. ∙ Criteria for evaluation: Technical correctness and clarity of the diagram.

Additional Requirements: 

∙ Warranty: At least 2-years post-installation warranty on system performance. ∙ Sustainability: Preference for companies that emphasize eco-friendly installation methods ∙ Workmanship Cost: Must be competitive and justifiable with the total project budget. ∙ Added Value: Proposals that offer added value aligned with the objectives of this call will be  viewed favorably.  

∙ Installation Timeline: Deployment of the solar system should not exceed 7 days from the date  of contract signing. 

∙ Local Involvement on Operations & Maintenance Training: The successful EPC should conduct  at least one (1) or a half (½) O&M check and training session with local technicians and  community beneficiaries to cover basic troubleshooting and operations. 

∙ Bid Security: Bidders must provide a bid security as a safeguard against non-performance,  project abandonment, or failure to complete the work within the agreed timeline. This guarantee  will be held by TENN and invoked in the event of default, delay, or misuse of project funds.  

TENN looks forward to receiving competitive bids that meet these requirements and contribute to  sustainable, community-driven development. 

This call for tender invites qualified contractors to be part of an impactful initiative that integrates  renewable energy with sustainable infrastructure development. For further details, please reach out via  the provided contact information. 

Note: Please note that TENN fully complies with all regulations of the National Revenue Authority  (NRA) mandates including its withholding income taxes.

TECHNICAL SPECIFICATIONS OF SOLUTIONS FOR 

INTEGRATED ENERGY CENTER IN FOGBO 

This document includes the solar system design and Bill of Material (BOM) for the Integrated Energy  Center located in Forbgo Community, Western Rural District. 

THE INTEGRATED ENERGY CENTER 

Please note that This system was Design with 30% increment for additional loads. 

Based on the assessment analysis, it appears that the load requirements are as such, for the 5 rooms IEC  which will have equipment (Including lights, freezers, mobile charging, Tailoring machines, Laptop  computer and Desktop computer & Dual Purpose printer with a consideration of 5 fans). 

LOAD DETAILS FOR THE IEC

Load Item		Power   (W)	Surge   Power   (W)	Quantity	Total   Power   (W)	Peak   Power   Rating   (W)	Hours   per   Day	Energy   Used   (Wh/day)
Desktop   computer		25		2	50	50	8	400
Light 01		7		10	70	70	12	840
light 02		30		7	210	210	11	2310
Fridge		68	204	2	136	408	14	1904
tailoring machine		250	750	2	500	1500	8	4000
Laptop		60		1	60	60	4	240
Dual-printer		250	750	1	250	750	6	1500
Phones		5		30	150	150	4	600
Fans		65		5	325	325	8	2600

 

BOM FOR IEC

Max units of energy (kWh) usage per  day (daily energy Demand)			16.4 kWh (units)
SL. No.	Products	Specification		Quantity
1	Solar PV Module (715W  Pmp; Panel) in four parallel  strings.	11.5 kWp		16
2	Solar Battery	46.8 kWh (48V Bus voltage) Lithium ion (51.2V rating)  (300 Ah, 48 V)		4

 

3	Roof Support Structure*	11.5 kWp  Roof Support Structure should consist of  both front and back legs to support the  panels. Galvanized Iron (G.I) – Roof Support Structure is preferred	To be verified
4	Solar MPPT Inverter – 230 Vac, 50 Hz	12.5kW, 48 V  Single Phase pure sine wave MPPT  inverter with 94% efficiency	1 No.
5	Solar MPPT Charge  Controller  (if the inverter does not have  inbuilt Charge controller)	75 A, 48V system also note that the CC  max.string voltage of 200volt and CC  max current of 15.1Kw, will be perfect.	1 No
6	Copper Cable Red + Black (Panel – Panel)	4 sq. mm (UV protected cable)	Based on the   number of panels
7	Copper Cable Red + Black (Panel – Inverter)	6 sq. mm	To be determine
8	Copper Cable Red + Black (Battery – Battery)	16 sq. mm	To be determine
9	Copper Cable Red + Black (Inverter – Load)	6 sq.mm	To be determine
10		4 sq. mm	To be determine
11		2.5 sq. mm	To be determine
12		1.5 sq. mm	To be determine
13	Earthing Cable (PV   connection box, Grid Input  Protection Box, & Inverter)	10 sq.mm (Tin-coated copper lugs with  insulation to be used at the cable – earth  electrode interface)	To be determine

 

14	Earthing Kit	Chemical earthing powder, solid copper  electrode, tin-coated copper lugs with  insulation, clamps with nut-bolts  assembly. Protective concrete   construction to earthing pit (L x B x H  1.5 x 1.5 x 1.5 feet) with metallic lid  should be made	2 Nos
15	Inverter elevation leg	Elevation rack with insulation Mat (or) 3  inch Leg Bush	1 Nos
16	PV Connection Box with  SPD  & MCB	Based on the panels connected in parallel
17	Double Pole MCB (load  side) with conduit box
18	Consumables	Consumables
19	Luminaries	As required based on design	To be verified
20	Solar Pump (Submersible)	1Hp, 120 Vac, 3 Phase	1
21	Solar Pump Controller	1Hp, 120 Vac, 3-Phase	1

 

*Roof Support Structure needs to be customized if the roof is tin sheet/ needs to be ground mounting. 

Notes: 

The above provided solar system design is for IEC only 

The solutions are AC powered only 

The addition of extra loads will not be encountered in the system design and connecting beyond the  mentioned capacity will result in system failure. 

Solar panels have to be mounted in the south direction in a shadow-free area. 

ANNEXURE 1 – TECHNICAL SPECIFICATIONS OF COMPONENTS 

The proposed project shall be commissioned as per the technical specifications given below. Any  shortcomings or deviations may lead to the cancellation of the Letter of Award, and in such a case  the Competent Authority’s decision will be final and binding on the bidder. 

1. SOLAR PV MODULE: 
2. The PV modules used must qualify to the latest edition of IEC PV module qualification  test or equivalent BIS standards Crystalline Silicon Solar Cell Modules IEC 

61215/IS14286. In addition, the modules must conform to IEC 61730 Part-2- requirements for construction & Part 2 – requirements for testing, for safety  qualification or equivalent IS. 

61701. For the PV modules to be used in a highly corrosive atmosphere throughout their  lifetime, they must qualify to IEC 61701/IS 61701. 
61702. The total solar PV array capacity should not be less than the allocated capacity and  should comprise solar crystalline modules of minimum Wp mentioned in the bill of  materials. Module capacity less than minimum mentioned kWp in the BoM / Purchase  Order shall not be accepted. 
61703. PV modules must be tested and approved by one of the IEC authorized test centers.  The module frame shall be made of corrosion-resistant materials, preferably anodized  aluminum. 
61704. Protective devices against surges at the PV module shall be provided. Low voltage drop  bypass diodes shall be provided. 
61705. The bidder shall carefully design & accommodate requisite numbers of the modules to  achieve the rated power in his bid 
61706. Other general requirement for the PV modules and subsystems shall be the Following: 
61707. The rated output power of any supplied module shall have tolerance of +/- 3%. ii. The peak-power point voltage and the peak-power point current of any  supplied module and/or any module string (series connected modules) shall  not vary by more than 2 (two) per cent from the respective arithmetic means  for all modules and/or for all module strings, as the case may be. 

iii. The module shall be provided with a junction box with either provision of  external screw terminal connection or sealed type and with arrangement for  provision of by-pass diode. The box shall have hinged, weather proof lid with  captive screws and cable gland entry points or may be of sealed type and IP 

65 rated. 

1. I-V curves at STC should be provided by bidder. 
2. Module Warranty:

Module Warranty is defined as: The manufacturer should warrant the Solar Module(s) to  be free from the defects and/or failures specified below for a period not less than five (5)  years from the date of sale to the original customer 

1. i) Defects and/or failures due to manufacturing. ii) 

Defects and/or failures due to quality of materials 

iii) Non-conformity to specifications due to faulty manufacturing and/or inspection  processes. If the solar Module(s) fails to conform to this warranty, the  

manufacturer will repair or replace the solar module(s), at the supplier’s sole  

cost 

1. Performance Warranty 

The degradation of power generated by the module shall not exceed 20% of the minimum  rated power over the 25-year period and not more than 10% after the first ten years’ period. 

III. Preferred Make 

Canadian Solar, Seraphim Solar Panels, Yingli Solar Panels, Sharp solar, JA Solar Bidder has  to take prior approval from the Foundation with sufficient certifications if other brands than  the above specified are considered by the bidder. 

2) ROOF SUPPORT STRUCTURE (RSS): 

1. a) Hot dip galvanized M.S/ anodized aluminum of size not less than 50 mm x 50 mm x 6 mm size  (for legs) and other square tubes of 2 mm thick (Rafter and Purlin) shall be used for mounting  the modules/ panels/arrays. Each structure should have an angle of inclination as per the site  conditions to take maximum irradiation. 
2. b) For a Flat Roof R.C.C installation, the RSS should be a minimum 2-legged structure (1 front  leg, 1 back leg) and many such leg pairs to exist along the length of the RSS, (Maximum  distance between each row pair should be 6 ft.). Each leg of RSS shall have a base plate at its  bottom. The base plate at each leg should be of the size 150*150*6 mm. The base plate should  have four stiffeners. Each stiffener will be placed perpendicular to the side of the base plate.  The base plate should house four wedge anchors at each corner. The steel wedge anchors used  should be 2-3 inches long (Depending upon the RCC roof thickness). 
3. c) The RSS should be designed such, it safely not only withstands the total panel weight but also  withstand the high wind loads acting over it. 
4. d) The PV panels should be clamped to RSS only at the allowable points along the panel frame,  which is specified by the panel manufacturer. Each panel should be clamped to the purlins using  4 clamps (2 clamps on each opposite sides of the panel). The clamps used should be of  minimum 35*3 mm size and that of anodized aluminum. The distance between the end clamp  and the end of the rail (purlin end) should be minimum 25 mm long. 
5. e) All panels and RSS should be grounded together with grounding bolts. 

Cyclone prone zones, high altitude-high wind zones (Particularly for flat RCC roof):

Additional measures should be taken to install PV panels at such high-risk zones. Installations at  such sites should have a low-elevation panel set-up made, along with “landscape” orientation of  PV panels (This would require a custom-made RSS viz triangular RSS frame/short legged RSS,  

preferably made with G.I). The PV panels should be mounted over the RSS using the “clamping”  method only. Anodized clamps of 45*4 mm size should be used here. 

The structure shall be designed to allow easy replacement of any module. The array structure shall  be so designed that it will occupy minimum space without sacrificing the output from the SPV  panels. Installation of solar structures should not damage the roof in any way. If any concrete or  foundation is required, it should be precast type. 

Fixed tilt systems, south facing with 24-26 degree inclined towards north should be followed  despite whatever roofing type is. This range is indicative and will depend on the actual location. 

The structure also should be able to withstand wind speed of 200 – 250 km/h. 

Bidders must follow any of the three types of roof mounting options and the solution is dependent  on the type of roof at the location. a) Flat roof, b) standing seam c) Shingle roof. In all cases,  considerations must be made for the roof’s age, structural integrity, access to equipment, and  necessary setbacks for fire and life safety requirements. 

The RSS should be mounted to the RCC roof using wedge anchor fasteners and a concrete block  of L x W x H = 1.5 x 1.5 x 1.5 feet respectively at each leg of the RSS. The sides of the cube and  roof interface should be given a simple 1-inch filet construction. At the top side of the cubes, an  upward taper should be formed from cube sides towards RSS leg. 

3) DC COMBINER BOX/ARRAY JUNCTION BOX: 

1. The junction boxes are to be provided in the PV array for termination of connecting cables. The  Junction Boxes (JBs) shall be made of GRP/FRP/Powder Coated Aluminum /cast aluminum  alloy with full dust, water & vermin proof arrangement. All wires/cables must be terminated  through cable lugs. The JBs shall be such that input & output termination can be made through  suitable cable glands. 
2. Each Junction Box shall have High quality Suitable Capacity Metal Oxide Varistors (MOVs) /  SPDs, suitable Reverse Blocking Diodes. The Junction Boxes shall have suitable arrangement  monitoring and disconnection for each of the group. 
3. Suitable markings shall be provided on the bus-bar for easy identification and the cable ferrules  must be fitted at the cable termination points for identification. The AJB should be placed in a  shaded place, preferably at the mid-end of the RSS legs. IP67 grade AJBs should be used. 

4) BATTERY: 

The battery type proposed: Lithium. 

1. All the batteries capacities mentioned are at 300Ah, 93% Efficiency and 75% DOD and the  same should also be followed by the bidder. However, bidders quoting for battery banks with  other capacities should add a justification note as annexure to why the particular voltage was  opted for. The technical committee will consider this and take a decision on the suitability of 

such an option. The decision of the technical committee/technical member of the buyer on this  matter will be final and binding on the bidder. 

1. Battery should conform to the latest BIS/ IEC/International standards. A copy of the relevant  test certificate for the battery should be furnished. 
2. The battery should be warranted for a minimum of 7 years. 
3. The battery should be installed inside the premises of consumers on a battery rack. The rack  material size should be able to easily bear the battery load. 
4. The battery rack should be of fireproof material and corrosion free (GI rack is preferable). f. Acid absorbent mats should be provided below the battery. The non-reactive acid proof mat  should be provided at the floor space of the battery bank. 
5. Tin-coated copper lugs (Ring type) with insulation to be used at cable ends to connect each  battery terminal. 
6. Spring washers to be incorporated in the nut-bolt assembly at each battery terminal. i. At each battery terminal, petroleum based Vaseline coating should be applied. ii. Battery  terminal caps used, should be big enough to cover the entire terminal area and the nut bolt  assembly. 
7. All cables connecting batteries should be provided “conduit pipe” protection and tied to the  outer sides of the battery body using cable ties. 

5) Single Phase Solar Inverter/ AC Charger: 

Solar Inverter of capacity & ratings as specified in the below for various capacities of Solar  Power Plants should convert DC power into AC power. Preference will be given to power  conditioning units conforming to standards IEC 61683. 

The inverter should be tested from the accredited testing- calibration laboratories. In the case of  imported inverter/AC charger units, these should be approved by international test houses. 

In case of inverters with low ground clearance (smaller capacity inverters), a minimum of 3-inch  elevation for the same should be incorporated. The elevating means should be a fireproof  material (Leg bushes are preferable). 

1. Inverter Specifications: 

• MOSFET/IGBT based. 
• Nominal Battery Voltage: 48 Vdc. 
• Inverter efficiency should be more than 93%. 
• Output voltage 230V, +/-2% pure sine wave for single phase. 
• Output frequency: 45 – 65 Hz, +/- 0.5 Hz 
• THD: Less than 3% 
• Operating Temperature Range: -20°C to 55°C 
• Operating humidity 95% maximum 
• Environmental Protection Index Should be IP 20.

1. Protections: 

• Over voltage (automatic shutdown) 
• Under voltage (automatic shutdown) 
• Overload – Short circuit (circuit breaker & electronics protection against sustained  fault) 
• Over Temperature 
• Battery reverse polarity 

1. Indicators 

• Battery connected, charging 
• Inverter ON 
• Grid charger on 
• Load on Grid/ Bypass 
• Grid on 
• warning /Fault 

1. Display Parameters 

• Charging current 
• Charging voltage 
• Voltage of PV panels 
• Output voltage 
• Grid voltage 
• Inverter loading (kW) & Energy Generation (kWh) 
• Output frequency 
• Fault / fault code 

1. Cooling: cooling mechanism required – Air Cooled 
2. Preferred Make: 

Studier, Victron, Schneider, SMA 

Bidder has to take prior approval from the Foundation with sufficient certifications if other  brands than the above specified are considered by the bidder. 

6) Charge Controller Specifications: 

Charge Controller contains an MPPT (Maximum Power Point Tracking) algorithm that continuously  tracks the maximum power point and automatically charges the batteries in an optimal way with all  the available solar power. 

• Indoor based 
• Charging Stages: 4 Stages: Bulk, Absorption, Floating, Equalization.
• Battery temperature compensation: 3mV/°C/Cell (25°C ref) default value with adjustable -8  to 0 mV/°C. 
• Operating ambient temperature range: -20 to 55°C. 
• Conversion efficiency should be more than 95%.  
• Comprehensive display. 
• Environmental Protection Index should be IP 54. 

1. Protections: 

• Over voltage (automatic shutdown) 
• Under voltage (automatic shutdown) 
• Overload – Short circuit (circuit breaker & electronics protection against sustained fault) ● Over Temperature. 
• Battery, PV reverse polarity. 

1. Indicators 

• Array on 
• MPPT charger on 
• Battery connected, charging 
• Battery status 
• Fault/ warnings 

III. Display Parameters 

• Charging current 
• Battery voltage 
• Voltage of PV panels 
• Energy Generation (kWh)- Today’s and cumulative 
• Fault / warning 

1. Preferred Make: 

Studier, Victron, Schneider, Outback, Tristar, SMA. 

Bidder has to take prior approval from the Foundation with sufficient certifications if other  brands than the above specified are considered by the bidder. 

7) Data Acquisition System/Plant Monitoring: 

• Data acquisition system for the entire Solar System. 
• Cloud based and local monitoring.
• Data logging provision for plant control and monitoring, time and date stamped system  data logs for analysis with the high quality, suitable PC, metering and instrumentation  for display of systems parameters and status indication to be provided. 
• The following parameters are accessible via the operating interface display in real time  separately for solar plant: 

▪ AC Voltage 

▪ AC Output Current 

▪ Output Power 

▪ Power Factor 

▪ DC Input Voltage ▪ 

DC Input Current 

▪ Power Produced 

▪ Energy kWH – today’s and cumulative. 

8) Protections 

The system should be provided with all necessary protections like earthing, lightning protection. 

9) Lightning Protection 

The main aim in this protection shall be to reduce the over voltage to a tolerable value before it  reaches the PV or other sub system components. The source of over voltage can be lightning,  atmosphere disturbances etc. The entire space occupying the SPV array shall be suitably protected  against lightning by deploying the required number of lightning arresters. 

To increase the coverage area of protection, the lightning arrestor should be given an additional  elevation by using anodized aluminum pole. The height of the lightning arrester point should be  minimum 3 meters above the height of the panels set. Insulation should be provided between the  lightning arrestor and the elevation pole. Down conductor should be provided with saddle  insulation along its length. (i.e. from the lightning arrestor till the earthing pit). Not more than 1m  gap should be maintained between two saddle insulators. Down conductors should maintain 0.5 m  distance from panels, arrays and other power cables around. 

The lightning arrestor setup should always be vertical and should be stable against high wind  loads. The lightning arrestor setup should be provided with anchor fasteners along with civil work  made at its base plate. A concrete cube (Civil work) of 1.5 ft x 1.5 ft x 1.5 ft (L x B x H)  dimensions should be set. If required, support wires should be used for additional stability of the  lightning arrestor. The lightning arrester should be placed preferably at the back of the array and at  the sides, with a separation distance of 0.5 meters only. 

The entire lightning arrester set up (Air terminal pole, spikes and base plates should be of solid  copper) 

10) Earthing

Earthing is a way of transmitting any instant electricity discharge directly to the ground by  providing a low resistance path (using electrical cables wires with no joints or metal strips with  lesser joints). This instant electricity discharge is mostly in the form of lightning, surge voltages  entering through grid lines and due to fault current/leakage current in the system. The goal is to  protect the appliances from voltage surges and protect the users from the risk of electrocution due  to leakage/fault current in the system. 

• Earthing type – Chemical Earthing 
• Earth electrodes should be that of solid copper. 
• Earth pit should be 1 foot by diameter and 4 ft by depth. 
• Separate earthing should be provided for these components: Lighting arrester, A.J.B,  Grid input protection box and Inverter. 
• Minimum of 3 m distance between each pit must be maintained and 1.5 m from building  foundations and sumps. 
• Should not combine AC earthing & DC Earthing. 
• Earthing pits should have a chamber set above the ground and should be closed with a  metallic lid/FRP lid. 
• Proper cable-to-rod & strip-to-rod clamps should be used.  
• Clamp materials should be that of copper alloys. 

11) Cables 

Cable size as mentioned in the bill of materials to be used in the project shall have the following  characteristics: 

• Temperature range: -10oC to +80oC. 
• Excellent resistance to heat, cold, water, oil, abrasion, UV radiation  
• Flexible 

Sizes of cables between array interconnections, array to junction boxes, junction boxes to Inverter  etc. shall be selected to keep the voltage drop (power loss) of the entire Project to the minimum. The  cables (as per IS) should be insulated with a special grade PVC compound formulated for outdoor  use. 

The Cable should be so selected that it should be compatible up to the life of the solar PV panels i.e.,  twenty-five (25) operational years. 

Cable ends should be crimped to cable lugs thoroughly using appropriate lugs. This lug interface has to  be Insulated. 

Tin-coated copper cable lugs with respect to cable sizes should be used and they should be of  required current ratings.

Conduit pipe protection to be given to cables connecting 1. Battery to battery, 2. Battery to inverter,  3. All cables entering the inverter. 

DC cables from the PV array and earthing cables should be given outdoor PVC (CPVC/UPVC) pipe  protection. DC cables entering the conduit pipes from the panel should be protected from the  rainwater with Sealing Gel. 

Cable Tie for Outdoor application should be UV resistant. 

Outdoor “L” bend pipes to be used wherever the cables pass through sharp edges/roof edges/angles in  the wall. 

Load wiring: 

Load wiring is to be redone in case of damaged (or) faulty wiring detected (Multiple cross  connections/power tapping). If in case, load wiring is not available at the health center, then a new  load wiring must be done for the energy efficient devices (Solar loads – Critical medical  equipment, luminaires and fans only) which are being installed in the center. For a new load  wiring proper solid conduit pipe protection should be provided. Cables of appropriate size should  be used. Cable color coding should be followed. Provision should be made during the wiring such  that solar power is not consumed by heavy loads and non-critical equipment in the center. 

1. Preferred Make: East African cables, Aberdare Power Cables, CBI African Cables.  

12) Tools & Tackles and Spares: 

After Completion of Installation & Commissioning of The Power Plant, Necessary Tools & Tackles  Shall Be Maintained by The Successful Bidder for Maintenance Purposes at The Local Service  Center. 

13) Safety Measures: 

The Bidder Shall Take Entire Responsibility for Electrical Safety Of The Installation(S) And  Follow All The Safety Rules & Regulations Applicable 

14) Luminaries and Accessories 

Preferred Make:

Led Bulbs/Tubes: Phillips,Osram, Energiser 

Ceiling Fan: Atomberg, Orient, Super Fan, Arizon. 

15) Operation and Maintenance Manual 

An Operation, Instruction and Maintenance Manual in English And/Or Local Language Should Be  Provided Along With The Solar System. The Following Minimum Details Must Be Provided in The Manual: 

• Basic Principles of Photovoltaics. 
• A Block Diagram On Solar Pv System – Showing Interconnection of its Components  Viz Pv Modules, Batteries, Inverters & Charge Controls and Loads. 
• A Small Write Up On Expected Performance of the Spv Systems. 
• A List of the Loads (Luminaire and Medical Equipment) That Are Connected to The  Solar Pv System. 
• A Separate List of Heavy Loads Which Are Never to Be Connected to The System. ● A List Containing Specification Details of Panels, Batteries, P.C.U., Showing Type of the Model Used, Model Number, Voltage & Current Capacity 
• A List of Total Numbers of Items (Solar Panels, Battery, Inverter, Earthing Pits,  Lightning Arresters, Luminaries, Fans and Medical Equipment) That Are Provided to The Center. 
• Significance of Audio and Visual Indicators of the Solar Pv System. 
• Clear Instructions On Regular Maintenance and Troubleshooting of the Solar Pv  System. 
• A List of Dos and Don’ts Practices While Handling the Solar Pv System. 
• Name, Address and Contact Details of the Customer Care Service/Service Provider for Repair Complaints and Scheduled & Unscheduled Maintenance  

Services. 

16) Annual Maintenance: 

• Two Scheduled Visits Per Year with 6 months of Interval Gap Should Be Done.
• Schedule Visits Should Consist of Basic Maintenance of the System – Cleaning of Panels, Checking of Wiring and Respective Connections, Cleaning Of 

Batteries, Filling of Distilled Water. 

• Checking and Verifying System Performance with Prescribed Format Provided.  

 

SEE ATTACHED LINKS BELOW;

BOM for IEC Solarization (1)