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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.

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

DeBeers Namibia published a tender for the supply and installation of a weather monitoring system at the Oranjemund Airport. CTS was awarded the tender based on price, knowledge of the meteorological measuring equipment as well as quality of products. At time of installation the station was the most advanced aviation weather station in Namibia.

Technical Details of the system installed:

• Ceilometer at end of runway 20 to measure cloud height at three levels up to 7,500m
• Runway Visibility and Present Weather sensor at stop end of runway 20.
• Present weather sensor monitors 7 different types of precipitation
• visibility sensor takes background luminescence into account
• Wind speed and direction a touchdown runway 20.
• Wind speed and direction, rain as well as barometric pressure at stop end runway 20
• AviMet server for processing of all data
• 3 workstations spread along the buildings for weather monitoring and supervision purposes
• ATIS voice system transmitting on aviation frequency as well as telephone dial in the current weather conditions

All communication between the equipment and the AviMet server is based on wireless transmission to reduce cabling costs.

The weather information can be picked up rough 100 NM away from the airport by all approaching aircraft.

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 In addition the offered lead acid battery technology has been replaced by state of the art lithium batteries reducing system maintenance.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

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

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.