A 7,3 kWp off-grid PV system was installed at the farm Heinrichsfelde in the Aus area with a Lithium-ion battery. The system is able to power an entire farmhouse. Remote monitorng and supervision is included.

System Specifications are:

• 24 x 305W Renesola PV modules
• 2x Victron MPPT 150/85
• 1x Victron Quattro 48/10000
• 1x BlueNova Lithium-ion battery 48V-24kWh
• Roof mounted with structure for IBR roof sheeting
• AC surge and lightning protection

A 71kW grid tied (Nampower ) PV system was installed at the Klein-Aus Vista Lodge just outside Aus. Remote Monitoring and Energy meter is included to obtain precise information about own consumption as well as exported power. This aids in future electrical reticulation upgrades and designs.

System Specifications are:

• 240 x 295W Canadian Solar PV modules
•  3 x Fronius Symo 20.0 – 3 Grid Inverter
• Shed roof mounting with structure for IBR roof sheeting
• AC & DC surge and Lightning protection
• Configured for remote monitoring

A new 7,1kWp Solar Home System for Net Metering was installed at a private residence in Windhoek.

System Specifications are:

• Grid connected with Net Metering
• 24 x 295W Canadian Solar PV modules. Total 7,1kWp.
• 1 x Fronius Primo 8,2-1
• Roof mounted with IBR sheeting
• Remote Monitoring and Energy Meter.

Central Technical Supplies was once again awarded the tender to electrify 4 remote localities in the Otjozondjupa Region of Namibia. Custom build containers where installed on site with SMA Sunny Island 8.0 inverter installed. In addition the offered lead acid battery technology has been replaced by state of the art lithium batteries reducing system maintenance. The use of AC coupled technology did allow for the SunnyBoy solar inverter to be in installed inside relevant buildings on which PV modules are mounted. All components are interlinked by means of wireless technology to allow for remote monitoring where GSM signal is of sufficient strength. System sizes vary form 3kW, 12kW, 15kW to 20kW of PV power while inverters are as much as 3 in a single phase cluster.

Sites that were electrified are:

• Nhoma
• Aasvoel Nes
• Kanovlei
• Grashoek

Various small off-grid PV systems, also referred to SHS (Solar Home Systems) have been supplied country wide. These systems are typically based on small high efficiency lithium ion batteries as storage solution and Victron components such as solar charge regulator, inverter and monitoring devices.

CTS has electrified two schools in remote northern Namibia funded by the Hanns Seidel Foundation with the aim to provide electricity for lighting, thus extending learning hours for learners well into the night. Both systems are based on BlueNova 4kWh lithium ion batteries, Victron Energy charge regulators and inverter technology. Remote monitoring is possible via the integrated Colour Control GX from Victron. Special attention has been given to the system configuration to prevent total battery shutdown. This is achieved by switching the inverter off at a predefined battery state of charge (typically 20%) and only reactivate the inverter once the batteries are charged beyond a predetermined threshold.

The systems where officially inaugurated by the Ambassador of Germany in June 2018.

An existing off-grid solar PV system was expanded to a total of 4,44kW on the farm Ombirisu north of Okahandja and the battery was upgraded to a Lithium-ion technology.

Final System Specifications:

• 6 x 295W Canadian Solar have been added to an existing PV array to deliver a final capacity of 4,44kW
• Replacing old charge regulators with 3 x Victron MPPT 150/70
• Replace old battery with 1 x BlueNova Lithium-ion battery 24V-24kWh
• Pole mounted solar array
• Online connection with remote access

A 200kW PV peak grid tied PV system was installed at Quality Tyres Lafrenz Industrial Area. Remote monitoring of all 10 inverter allows for early fault detection and system degradation as well as maintenance planing.

System Specifications are:

• 680x 295W Canadian Solar modules
• 10x Fronius Symo 20.0-3 Grid Inverter
• Roof mounting structure for IBR roof sheeting
• AC surge protection
• configured for remote monitoring

In early 2017 Stier Vente Chartered Accountant did take the decision to move to renewable energy. A 17kW grid feed system was installed on the roof of the office building to reduce the monthly electricity bill.

A total of 67 260W PV modules and a SMA SunnyTripower 17kW inverter was installed. Remote monitoring allows CTS to advise the client on possible faults and recommended actions to be taken.

Pionieerspark Medical Centre can call themselves a proud owner of a 38kW photovoltaic grid feed system. Considerable savings on the monthly electricity bill are achieved as most of the electricity requirements are produced directly at the customer. Excess energy is fed back into the grid and credited on the monthly electricity bill by City of Windhoek.

The system consists of 144 265W PV modules mounted flat on the roof of the building with 2 Fronius three phase grid feed inverters and remote monitoring via the Fronius App on the cell phone. Remote monitoring allows CTS to advise the client on possible faults and recommended actions to be taken.

Three localities in the Otjozondjupa region where successfully electrified by means of Off-Grid PV containers. The system sizes varied from 6kW, 12kW to 25kW of PV power. PV modules where installed on roofs of nearby houses, batteries, inverter/charger and switchgear are located in our proven design of prefabricated containers to keep the components cool, even in the hottest of climates.

The system is an AC coupled PV system with SMA Sunny Island (SI 8.0) inverter and SunnyBoys of various sizes. Communication between all components is based on a wireless RS485 solution from Phoenix Contact with a distance covered of 1.5km.

Sites that were electrified in the Otjozondjupa region are:

• Rooidag Hek 
• M’Kata
• Kukurushe

An off gird PV system with generator back up was installed at the Gcwatjinga clinic south east of Rundu. The system comprises of the following components:

• 6.24 kW PV array
• 2x Victron BueSolar 150V/70A MPPT regulator
• 600Ah Battery capacity
• Inverter/Charger, Victron Multi, 48V/8000VA
• System Monitoring (BMV700, Color Control GX)

The clinic was connected to the grid, which at time of system design and installation the grid connection plans were unknown to the engineer. As the clinic has PV installed, the existing system has been configured such as to allow for grid connection once the batteries reach a predefined SOC. This guarantees a continuous supply of power to the clinic and nurse houses.

In addition to the grid, a backup generator is incorporated in case PV as well as grid failure occur.

The installed photovoltaic system at Elavi Clinic caters for the power supply to the clinic as well as the nurse houses. A 6.2kW PV module array generates enough power for the energy requirements. Should this not be sufficient the batteries can be charged by a backup generator.

The system consists of the following:

• 6.24 kW PV array
• 2x Victron BueSolar 150V/70A MPPT regulator
• 600Ah Battery capacity
• Inverter/Charger, Victron Multi, 48V/8000VA
• System Monitoring (BMV700, Color Control GX)

After successful completion of the Omusati off grid electrification project, CTS was successful in winning the bid for the second phase of containerized PV solutions for the Kunene region. With the experience gained from phase 1, the containers were optimized in many ways. The final design consisted custom build 20ft container by Namspace in Swakopmund.

Sites that were electrified in the Kunene region are:

• Otjitjekua School
• Otjiu School
• Otjiu Hostel
• Epupa School

The project included the following:

• Upgrading of all government building wiring as per national standard for 4 sites in the Kunene region:
• Manufacture, supply and install container power units for these sites.

The power containers consisted of ca 2.8kW of PV modules installed on the roof as well as 4,500 Ah of battery capacity. Five kVA inverter charger and two 70A BlueSolar Charge regulator all from Victron Energy complete the system. Remote monitoring of all sites is achieved by using the Victron Color Control GX unit.

CTS was awarded the first ever containerized off-grid solar electrification tender for the Ministry of Mines and Energy beginning of 2013. This project entailed:

• Upgrading of all government building wiring as per national standard for 9 sites in the Omusati region
• Manufacture, supply and install container power units for these sites.

The power containers consisted of ca 2.8kW of PV modules installed on the roof as well as 3,000 to 4,500 Ah of battery capacity depending on site requirements. Five KVA inverter charger and two 70A Blue Solar Charge regulator all from Victron Energy complete the system.

With a total of nine containers, school, hostels and other government buildings were electrified. Each container was subdivided into two rooms for batteries and inverter technology respectively.

With our 36T/m crane truck CTS was able to transport the container to site, navigating through thick sand with ease.

This is a typical photovoltaic (PV) medium scale farm system found on many farms around Namibia. Over the past three years this system grew in PV size from 350Wpeak to ~1200Wpeak.

System specs are:

• PV modules with a total capacity of 1220Wpeak
• 1200VA, 24V Inverter charger
• 40A Solar Charge Regulator
• 360Ah battery bank@24V
• Battery Monitor showing: state of charge (%), charging/discharging current (A), Battery Voltage (V) and time to go (h)
• Switchgear for submersible pump control

The PV modules are mounted on frames facing true north for optimal energy harvesting. During times of limited sunshine, especially the rainy season, battery charging can be increased by starting the generator. Should the AC load increase behind the inverter rating, the generator can support the system to cater for the increased load. No automatic generator start function is included.

Furthermore a second PV system for the Farm workers has been installed to cater for lighting and a TV.

• 2x 90Wpeak PV modules
• 20A Solar Charge Regulator
• 2x 105Ah batteries
• 350VA, 12V inverter

CTS was approached by a senior resident of Klein Windhoek to install a grid-tied photovoltaic system with the aim to cut back on the monthly electricity bill. The system included:

• 42x 130W photovoltaic modules and mounting structure
• 1x 6kW grid tied inverter

The system is designed such as to generate an estimated 900kWh per month.