Home | Central Technical Supplies

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 the Botswana Meteorological Department and the University of Hamburg with the request to install automatic weather stations across Botswana. A total of 10 stations were engineered and build at our workshop in Windhoek prior to installation commencement. With our own tower design, the installation time is reduced to nearly 8 hours per tower.

The stations are equipped with sensors from Vaisala, Kipp and Zonen. At the heart of each station is the CR1000 logger from Campbell Scientific. Each station is capable to measure the following:

• Wind speed
• Wind direction
• Humidity
• Air Temperature
• Irradiance
• Barometric pressure
• Ground Temperature
• Rain
• Leaf wetness

In addition to the above parameters the following parameters are calculated by the logger by means of mathematical models.

• Dew point temperature
• Wet bulb temperature
• Sunshine duration

The data from the station is transmitted to ftp servers situated in Gaborone/Botswana as well as Hamburg/Germany on an hourly bases over locally available GSM network providers. Once the data is uploaded to the server in Hamburg, it is processed and posted on a publicly available website. This website collects data of numerous stations across Namibia, Botswana, Zambia, Angola and South Africa for research purposes. A total of 8000km was covered in just under 4 weeks.

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.

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.

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

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.